JPMS: Changes to the Java Debug Wire Protocol
2017/8/21 15:24 -0700 [52c38248458b]
Copyright © 2017 Oracle and/or its affiliates · All Rights Reserved ·
LicenseReturns the JDWP version implemented by the target VM. The
version string format is implementation dependent.
- Out Data
- (None)
- Reply Data
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string |
description |
Text information on the VM version |
int |
jdwpMajor |
Major JDWP Version number |
int |
jdwpMinor |
Minor JDWP Version number |
string |
vmVersion |
Target VM JRE version, as in the java.version
property |
string |
vmName |
Target VM name, as in the java.vm.name
property |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Returns reference types for all the classes loaded by the target
VM which match the given signature. Multple reference types will be
returned if two or more class loaders have loaded a class of the
same name. The search is confined to loaded classes only; no
attempt is made to load a class of the given signature.
- Out Data
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string |
signature |
JNI signature of the class to find (for example,
"Ljava/lang/String;"). Â |
- Reply Data
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int |
classes |
Number of reference types that follow. |
Repeated classes times: |
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byte |
refTypeTag |
Kind of following reference type.
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referenceTypeID |
typeID |
Matching loaded reference type |
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int |
status |
The current class status.
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- Error Data
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VM_DEAD |
The virtual machine is not running. |
Returns reference types for all classes currently loaded by the
target VM.
- Out Data
- (None)
- Reply Data
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int |
classes |
Number of reference types that follow. |
Repeated classes times: |
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byte |
refTypeTag |
Kind of following reference type.
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referenceTypeID |
typeID |
Loaded reference type |
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string |
signature |
The JNI signature of the loaded reference type |
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int |
status |
The current class status.
 |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Returns all threads currently running in the target VM . The
returned list contains threads created through java.lang.Thread,
all native threads attached to the target VM through JNI, and
system threads created by the target VM. Threads that have not yet
been started and threads that have completed their execution are
not included in the returned list.
- Out Data
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int |
threads |
Number of threads that follow. |
Repeated threads times: |
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threadID |
thread |
A running thread |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Returns all thread groups that do not have a parent. This
command may be used as the first step in building a tree (or trees)
of the existing thread groups.
- Out Data
- (None)
- Reply Data
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int |
groups |
Number of thread groups that follow. |
Repeated groups times: |
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threadGroupID |
group |
A top level thread group |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Invalidates this virtual machine mirror. The communication
channel to the target VM is closed, and the target VM prepares to
accept another subsequent connection from this debugger or another
debugger, including the following tasks:
- All event requests are cancelled.
- All threads suspended by the thread-level resume command or the VM-level
resume command are
resumed as many times as necessary for them to run.
- Garbage collection is re-enabled in all cases where it was
disabled
Any current method invocations executing in the target VM are
continued after the disconnection. Upon completion of any such
method invocation, the invoking thread continues from the location
where it was originally stopped.
Resources originating in this VirtualMachine (ObjectReferences,
ReferenceTypes, etc.) will become invalid.
- Out Data
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- Reply Data
- (None)
- Error Data
- (None)
Returns the sizes of variably-sized data types in the target
VM.The returned values indicate the number of bytes used by the
identifiers in command and reply packets.
- Out Data
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- Reply Data
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int |
fieldIDSize |
fieldID size in bytes  |
int |
methodIDSize |
methodID size in bytes  |
int |
objectIDSize |
objectID size in bytes  |
int |
referenceTypeIDSize |
referenceTypeID size in bytes  |
int |
frameIDSize |
frameID size in bytes  |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Suspends the execution of the application running in the target
VM. All Java threads currently running will be suspended.
Unlike java.lang.Thread.suspend, suspends of both the virtual
machine and individual threads are counted. Before a thread will
run again, it must be resumed through the VM-level resume command or the
thread-level resume
command the same number of times it has been suspended.
- Out Data
- (None)
- Reply Data
- (None)
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Resumes execution of the application after the suspend command
or an event has stopped it. Suspensions of the Virtual Machine and
individual threads are counted. If a particular thread is suspended
n times, it must resumed n times before it will continue.
- Out Data
- (None)
- Reply Data
- (None)
- Error Data
- (None)
Terminates the target VM with the given exit code. On some
platforms, the exit code might be truncated, for example, to the
low order 8 bits. All ids previously returned from the target VM
become invalid. Threads running in the VM are abruptly terminated.
A thread death exception is not thrown and finally blocks are not
run.
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int |
exitCode |
the exit code |
- Reply Data
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- Error Data
- (None)
Creates a new string object in the target VM and returns its
id.
- Out Data
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string |
utf |
UTF-8 characters to use in the created string.
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stringID |
stringObject |
Created string (instance of java.lang.String) Â |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Retrieve this VM's capabilities. The capabilities are returned
as booleans, each indicating the presence or absence of a
capability. The commands associated with each capability will
return the NOT_IMPLEMENTED error if the cabability is not
available.
- Out Data
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boolean |
canWatchFieldModification |
Can the VM watch field modification, and therefore can it send
the Modification Watchpoint Event? |
boolean |
canWatchFieldAccess |
Can the VM watch field access, and therefore can it send the
Access Watchpoint Event? |
boolean |
canGetBytecodes |
Can the VM get the bytecodes of a given method?
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boolean |
canGetSyntheticAttribute |
Can the VM determine whether a field or method is synthetic?
(that is, can the VM determine if the method or the field was
invented by the compiler?) Â |
boolean |
canGetOwnedMonitorInfo |
Can the VM get the owned monitors infornation for a
thread? |
boolean |
canGetCurrentContendedMonitor |
Can the VM get the current contended monitor of a
thread? |
boolean |
canGetMonitorInfo |
Can the VM get the monitor information for a given object?
 |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Retrieve the classpath and bootclasspath of the target VM. If
the classpath is not defined, returns an empty list. If the
bootclasspath is not defined returns an empty list.
- Out Data
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- Reply Data
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string |
baseDir |
Base directory used to resolve relative paths in either of the
following lists. |
int |
classpaths |
Number of paths in classpath. |
Repeated classpaths times: |
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string |
path |
One component of classpath |
int |
bootclasspaths |
Number of paths in bootclasspath. |
Repeated bootclasspaths times: |
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string |
path |
One component of bootclasspath |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Releases a list of object IDs. For each object in the list, the
following applies. The count of references held by the back-end
(the reference count) will be decremented by refCnt. If thereafter
the reference count is less than or equal to zero, the ID is freed.
Any back-end resources associated with the freed ID may be freed,
and if garbage collection was disabled for the object, it will be
re-enabled. The sender of this command promises that no further
commands will be sent referencing a freed ID.
Use of this command is not required. If it is not sent,
resources associated with each ID will be freed by the back-end at
some time after the corresponding object is garbage collected. It
is most useful to use this command to reduce the load on the
back-end if a very large number of objects has been retrieved from
the back-end (a large array, for example) but may not be garbage
collected any time soon.
IDs may be re-used by the back-end after they have been freed
with this command.This description assumes reference counting, a
back-end may use any implementation which operates
equivalently.
- Out Data
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int |
requests |
Number of object dispose requests that follow |
Repeated requests times: |
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objectID |
object |
The object IDÂ |
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int |
refCnt |
The number of times this object ID has been part of a packet
received from the back-end. An accurate count prevents the object
ID from being freed on the back-end if it is part of an incoming
packet, not yet handled by the front-end. |
- Reply Data
- (None)
- Error Data
- (None)
Tells the target VM to stop sending events. Events are not
discarded; they are held until a subsequent ReleaseEvents command
is sent. This command is useful to control the number of events
sent to the debugger VM in situations where very large numbers of
events are generated. While events are held by the debugger
back-end, application execution may be frozen by the debugger
back-end to prevent buffer overflows on the back end.Responses to
commands are never held and are not affected by thiscommand. If
events are already being held, this command is ignored.
- Out Data
- (None)
- Reply Data
- (None)
- Error Data
- (None)
Tells the target VM to continue sending events. This command is
used to restore normal activity after a HoldEvents command. If
there is no current HoldEvents command in effect, this command is
ignored.
- Out Data
- (None)
- Reply Data
- (None)
- Error Data
- (None)
Retrieve all of this VM's capabilities. The capabilities are
returned as booleans, each indicating the presence or absence of a
capability. The commands associated with each capability will
return the NOT_IMPLEMENTED error if the cabability is not
available.Since JDWP version 1.4.
- Out Data
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- Reply Data
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boolean |
canWatchFieldModification |
Can the VM watch field modification, and therefore can it send
the Modification Watchpoint Event? |
boolean |
canWatchFieldAccess |
Can the VM watch field access, and therefore can it send the
Access Watchpoint Event? |
boolean |
canGetBytecodes |
Can the VM get the bytecodes of a given method?
 |
boolean |
canGetSyntheticAttribute |
Can the VM determine whether a field or method is synthetic?
(that is, can the VM determine if the method or the field was
invented by the compiler?) Â |
boolean |
canGetOwnedMonitorInfo |
Can the VM get the owned monitors infornation for a
thread? |
boolean |
canGetCurrentContendedMonitor |
Can the VM get the current contended monitor of a
thread? |
boolean |
canGetMonitorInfo |
Can the VM get the monitor information for a given object?
 |
boolean |
canRedefineClasses |
Can the VM redefine classes? |
boolean |
canAddMethod |
Can the VM add methods when redefining
classes? |
boolean |
canUnrestrictedlyRedefineClasses |
Can the VM redefine classesin arbitrary ways? |
boolean |
canPopFrames |
Can the VM pop stack frames? |
boolean |
canUseInstanceFilters |
Can the VM filter events by specific object? |
boolean |
canGetSourceDebugExtension |
Can the VM get the source debug extension? |
boolean |
canRequestVMDeathEvent |
Can the VM request VM death events? |
boolean |
canSetDefaultStratum |
Can the VM set a default stratum? |
boolean |
canGetInstanceInfo |
Can the VM return instances, counts of instances of classes and
referring objects? |
boolean |
canRequestMonitorEvents |
Can the VM request monitor events? |
boolean |
canGetMonitorFrameInfo |
Can the VM get monitors with frame depth info? |
boolean |
canUseSourceNameFilters |
Can the VM filter class prepare events by source
name? |
boolean |
canGetConstantPool |
Can the VM return the constant pool
information? |
boolean |
canForceEarlyReturn |
Can the VM force early return from a method? |
boolean |
reserved22 |
Reserved for future capability |
boolean |
reserved23 |
Reserved for future capability |
boolean |
reserved24 |
Reserved for future capability |
boolean |
reserved25 |
Reserved for future capability |
boolean |
reserved26 |
Reserved for future capability |
boolean |
reserved27 |
Reserved for future capability |
boolean |
reserved28 |
Reserved for future capability |
boolean |
reserved29 |
Reserved for future capability |
boolean |
reserved30 |
Reserved for future capability |
boolean |
reserved31 |
Reserved for future capability |
boolean |
reserved32 |
Reserved for future capability |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Installs new class definitions. If there are active stack frames
in methods of the redefined classes in the target VM then those
active frames continue to run the bytecodes of the original method.
These methods are considered obsolete - see IsObsolete. The methods in the
redefined classes will be used for new invokes in the target VM.
The original method ID refers to the redefined method. All
breakpoints in the redefined classes are cleared.If resetting of
stack frames is desired, the PopFrames command can be used to
pop frames with obsolete methods.
Requires canRedefineClasses capability - see CapabilitiesNew. In
addition to the canRedefineClasses capability, the target VM must
have the canAddMethod capability to add methods when redefining
classes, or the canUnrestrictedlyRedefineClasses to redefine
classes in arbitrary ways.
- Out Data
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int |
classes |
Number of reference types that follow. |
Repeated classes times: |
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referenceTypeID |
refType |
The reference type. |
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int |
classfile |
Number of bytes defining class (below)Â |
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Repeated classfile times: |
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byte |
classbyte |
byte in JVM class file format. |
- Reply Data
- (None)
- Error Data
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INVALID_CLASS |
One of the refTypes is not the ID of a reference
type. |
INVALID_OBJECT |
One of the refTypes is not a known ID. |
UNSUPPORTED_VERSION |
A class file has a version number not supported by this
VM. |
INVALID_CLASS_FORMAT |
The virtual machine attempted to read a class file and
determined that the file is malformed or otherwise cannot be
interpreted as a class file. |
CIRCULAR_CLASS_DEFINITION |
A circularity has been detected while initializing a
class. |
FAILS_VERIFICATION |
The verifier detected that a class file, though well formed,
contained some sort of internal inconsistency or security
problem. |
NAMES_DONT_MATCH |
The class name defined in the new class file is different from
the name in the old class object. |
NOT_IMPLEMENTED |
No aspect of this functionality is implemented
(CapabilitiesNew.canRedefineClasses is false)Â |
ADD_METHOD_NOT_IMPLEMENTED |
Adding methods has not been implemented. |
SCHEMA_CHANGE_NOT_IMPLEMENTED |
Schema change has not been implemented. |
HIERARCHY_CHANGE_NOT_IMPLEMENTED |
A direct superclass is different for the new class version, or
the set of directly implemented interfaces is different and
canUnrestrictedlyRedefineClasses is false. |
DELETE_METHOD_NOT_IMPLEMENTED |
The new class version does not declare a method declared in the
old class version and canUnrestrictedlyRedefineClasses is
false. |
CLASS_MODIFIERS_CHANGE_NOT_IMPLEMENTED |
The new class version has different modifiers and and
canUnrestrictedlyRedefineClasses is false. |
METHOD_MODIFIERS_CHANGE_NOT_IMPLEMENTED |
A method in the new class version has different modifiers than
its counterpart in the old class version and and
canUnrestrictedlyRedefineClasses is false. |
VM_DEAD |
The virtual machine is not running. |
Set the default stratum. Requires canSetDefaultStratum
capability - see CapabilitiesNew.
- Out Data
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string |
stratumID |
default stratum, or empty string to use reference type
default. |
- Reply Data
- (None)
- Error Data
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NOT_IMPLEMENTED |
The functionality is not implemented in this virtual
machine. |
VM_DEAD |
The virtual machine is not running. |
Returns reference types for all classes currently loaded by the
target VM. Both the JNI signature and the generic signature are
returned for each class. Generic signatures are described in the
signature attribute section in The Javaâ„¢
Virtual Machine Specification. Since JDWP version 1.5.
- Out Data
- (None)
- Reply Data
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int |
classes |
Number of reference types that follow. |
Repeated classes times: |
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byte |
refTypeTag |
Kind of following reference type.
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referenceTypeID |
typeID |
Loaded reference type |
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string |
signature |
The JNI signature of the loaded reference
type. |
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string |
genericSignature |
The generic signature of the loaded reference type or an empty
string if there is none. |
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int |
status |
The current class status.
 |
- Error Data
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VM_DEAD |
The virtual machine is not running. |
Returns the number of instances of each reference type in the
input list. Only instances that are reachable for the purposes of
garbage collection are counted. If a reference type is invalid, eg.
it has been unloaded, zero is returned for its instance count.
Since JDWP version 1.6. Requires canGetInstanceInfo capability -
see CapabilitiesNew.
- Out Data
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int |
refTypesCount |
Number of reference types that follow. Must be
non-negative. |
Repeated refTypesCount times: |
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referenceTypeID |
refType |
A reference type ID. |
- Reply Data
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int |
counts |
The number of counts that follow. |
Repeated counts times: |
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long |
instanceCount |
The number of instances for the corresponding reference type in
'Out Data'. |
- Error Data
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Returns all modules in the
target VM.
Since JDWP version 9.
- Out Data
- (None)
- Reply Data
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int |
modules |
The number of the modules that
follow. |
Repeated modules times: |
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moduleID |
module |
One of the
modules. |
- Error Data
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NOT_IMPLEMENTED |
The functionality is not
implemented in this virtual machine. |
VM_DEAD |
The virtual machine is not
running. |
Returns the JNI signature of a reference type. JNI signature
formats are described in the Java
Native Inteface Specification
For primitive classes the returned signature is the signature of
the corresponding primitive type; for example, "I" is returned as
the signature of the class represented by
java.lang.Integer.TYPE.
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
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string |
signature |
The JNI signature for the reference type. |
- Error Data
-
Returns the instance of java.lang.ClassLoader which loaded a
given reference type. If the reference type was loaded by the
system class loader, the returned object ID is null.
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
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classLoaderID |
classLoader |
The class loader for the reference type. Â |
- Error Data
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Returns the modifiers (also known as access flags) for a
reference type. The returned bit mask contains information on the
declaration of the reference type. If the reference type is an
array or a primitive class (for example, java.lang.Integer.TYPE),
the value of the returned bit mask is undefined.
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
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int |
modBits |
Modifier bits as defined in Chapter 4 of The
Javaâ„¢ Virtual Machine
Specification |
- Error Data
-
Returns information for each field in a reference type.
Inherited fields are not included. The field list will include any
synthetic fields created by the compiler. Fields are returned in
the order they occur in the class file.
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
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int |
declared |
Number of declared fields. |
Repeated declared times: |
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fieldID |
fieldID |
Field ID. |
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string |
name |
Name of field. |
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string |
signature |
JNI Signature of field. |
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int |
modBits |
The modifier bit flags (also known as access flags) which
provide additional information on the field declaration. Individual
flag values are defined in Chapter 4 of The
Javaâ„¢ Virtual Machine Specification. In
addition, The 0xf0000000 bit identifies the field as
synthetic, if the synthetic attribute capability is
available. |
- Error Data
-
Returns information for each method in a reference type.
Inherited methods are not included. The list of methods will
include constructors (identified with the name "<init>"), the
initialization method (identified with the name "<clinit>")
if present, and any synthetic methods created by the compiler.
Methods are returned in the order they occur in the class file.
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
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int |
declared |
Number of declared methods. |
Repeated declared times: |
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methodID |
methodID |
Method ID. |
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string |
name |
Name of method. |
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string |
signature |
JNI signature of method. |
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int |
modBits |
The modifier bit flags (also known as access flags) which
provide additional information on the method declaration.
Individual flag values are defined in Chapter 4 of The
Javaâ„¢ Virtual Machine Specification. In
addition, The 0xf0000000 bit identifies the method as
synthetic, if the synthetic attribute capability is
available. |
- Error Data
-
Returns the value of one or more static fields of the reference
type. Each field must be member of the reference type or one of its
superclasses, superinterfaces, or implemented interfaces. Access
control is not enforced; for example, the values of private fields
can be obtained.
- Out Data
-
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referenceTypeID |
refType |
The reference type ID. |
int |
fields |
The number of values to get |
Repeated fields times: |
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fieldID |
fieldID |
A field to get |
- Reply Data
-
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int |
values |
The number of values returned, always equal to fields, the
number of values to get. |
Repeated values times: |
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value |
value |
The field value |
- Error Data
-
Returns the name of source file in which a reference type was
declared.
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
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string |
sourceFile |
The source file name. No path information for the file is
included |
- Error Data
-
Returns the classes and interfaces directly nested within this
type.Types further nested within those types are not included.
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
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int |
classes |
The number of nested classes and interfaces |
Repeated classes times: |
|
byte |
refTypeTag |
Kind of following reference type.
 |
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referenceTypeID |
typeID |
The nested class or interface ID. |
- Error Data
-
Returns the current status of the reference type. The status
indicates the extent to which the reference type has been
initialized, as described in section 2.1.6 of The
Javaâ„¢ Virtual Machine Specification. If
the class is linked the PREPARED and VERIFIED bits in the returned
status bits will be set. If the class is initialized the
INITIALIZED bit in the returned status bits will be set. If an
error occured during initialization then the ERROR bit in the
returned status bits will be set. The returned status bits are
undefined for array types and for primitive classes (such as
java.lang.Integer.TYPE).
- Out Data
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
- Error Data
-
Returns the interfaces declared as implemented by this class.
Interfaces indirectly implemented (extended by the implemented
interface or implemented by a superclass) are not included.
- Out Data
-
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referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
|
|
|
|
|
|
|
int |
interfaces |
The number of implemented interfaces |
Repeated interfaces times: |
|
interfaceID |
interfaceType |
implemented interface. |
- Error Data
-
Returns the class object corresponding to this type.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
|
|
|
|
|
|
|
classObjectID |
classObject |
class object. |
- Error Data
-
Returns the value of the SourceDebugExtension attribute. Since
JDWP version 1.4. Requires canGetSourceDebugExtension capability -
see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
|
|
|
|
|
|
|
string |
extension |
extension attribute |
- Error Data
-
Returns the JNI signature of a reference type along with the
generic signature if there is one. Generic signatures are described
in the signature attribute section in The
Javaâ„¢ Virtual Machine Specification. Since
JDWP version 1.5.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
|
|
|
|
|
|
|
string |
signature |
The JNI signature for the reference type. |
string |
genericSignature |
The generic signature for the reference type or an empty string
if there is none. |
- Error Data
-
Returns information, including the generic signature if any, for
each field in a reference type. Inherited fields are not included.
The field list will include any synthetic fields created by the
compiler. Fields are returned in the order they occur in the class
file. Generic signatures are described in the signature attribute
section in The Javaâ„¢ Virtual Machine
Specification. Since JDWP version 1.5.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
|
|
|
|
|
|
|
int |
declared |
Number of declared fields. |
Repeated declared times: |
|
fieldID |
fieldID |
Field ID. |
|
string |
name |
The name of the field. |
|
string |
signature |
The JNI signature of the field. |
|
string |
genericSignature |
The generic signature of the field, or an empty string if there
is none. |
|
int |
modBits |
The modifier bit flags (also known as access flags) which
provide additional information on the field declaration. Individual
flag values are defined in Chapter 4 of The
Javaâ„¢ Virtual Machine Specification. In
addition, The 0xf0000000 bit identifies the field as
synthetic, if the synthetic attribute capability is
available. |
- Error Data
-
Returns information, including the generic signature if any, for
each method in a reference type. Inherited methodss are not
included. The list of methods will include constructors (identified
with the name "<init>"), the initialization method
(identified with the name "<clinit>") if present, and any
synthetic methods created by the compiler. Methods are returned in
the order they occur in the class file. Generic signatures are
described in the signature attribute section in The
Javaâ„¢ Virtual Machine Specification. Since
JDWP version 1.5.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The reference type ID. |
- Reply Data
-
|
|
|
|
|
|
|
int |
declared |
Number of declared methods. |
Repeated declared times: |
|
methodID |
methodID |
Method ID. |
|
string |
name |
The name of the method. |
|
string |
signature |
The JNI signature of the method. |
|
string |
genericSignature |
The generic signature of the method, or an empty string if
there is none. |
|
int |
modBits |
The modifier bit flags (also known as access flags) which
provide additional information on the method declaration.
Individual flag values are defined in Chapter 4 of The
Javaâ„¢ Virtual Machine Specification. In
addition, The 0xf0000000 bit identifies the method as
synthetic, if the synthetic attribute capability is
available. |
- Error Data
-
Returns instances of this reference type. Only instances that
are reachable for the purposes of garbage collection are
returned.
Since JDWP version 1.6. Requires canGetInstanceInfo capability -
see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The reference type ID. |
int |
maxInstances |
Maximum number of instances to return. Must be non-negative. If
zero, all instances are returned. |
- Reply Data
-
|
|
|
|
|
|
|
int |
instances |
The number of instances that follow. |
Repeated instances times: |
|
tagged-objectID |
instance |
An instance of this reference type. |
- Error Data
-
Returns the class file major and minor version numbers, as
defined in the class file format of the Java Virtual Machine
specification.
Since JDWP version 1.6.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The class. |
- Reply Data
-
|
|
|
|
|
|
|
int |
majorVersion |
Major version number |
int |
minorVersion |
Minor version number |
- Error Data
-
Return the raw bytes of the constant pool in the format of the
constant_pool item of the Class File Format in The
Javaâ„¢ Virtual Machine Specification.
Since JDWP version 1.6. Requires canGetConstantPool capability -
see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The class. |
- Reply Data
-
|
|
|
|
|
|
|
int |
count |
Total number of constant pool entries plus one. This
corresponds to the constant_pool_count item of the Class File
Format in The Javaâ„¢ Virtual Machine
Specification. Â |
int |
bytes |
 |
Repeated bytes times: |
|
byte |
cpbytes |
Raw bytes of constant pool |
- Error Data
-
INVALID_CLASS |
refType is not the ID of a reference type. |
INVALID_OBJECT |
refType is not a known ID. |
NOT_IMPLEMENTED |
If the target virtual machine does not support the retrieval of
constant pool information. |
ABSENT_INFORMATION |
The Constant Pool information is absent for primitive and array
types. |
VM_DEAD |
The virtual machine is not running. |
Returns the module that this
reference type belongs to.
Since JDWP version 9.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The reference
type. |
- Reply Data
-
|
|
|
|
|
|
|
moduleID |
module |
The module this reference type
belongs to. |
- Error Data
-
Returns the immediate superclass of a class.
- Out Data
-
|
|
|
|
|
|
|
classID |
clazz |
The class type ID. |
- Reply Data
-
|
|
|
|
|
|
|
classID |
superclass |
The superclass (null if the class ID for java.lang.Object is
specified). |
- Error Data
-
Sets the value of one or more static fields. Each field must be
member of the class type or one of its superclasses,
superinterfaces, or implemented interfaces. Access control is not
enforced; for example, the values of private fields can be set.
Final fields cannot be set.For primitive values, the value's type
must match the field's type exactly. For object values, there must
exist a widening reference conversion from the value's type to
thefield's type and the field's type must be loaded.
- Out Data
-
|
|
|
|
|
|
|
classID |
clazz |
The class type ID. |
int |
values |
The number of fields to set. |
Repeated values times: |
|
fieldID |
fieldID |
Field to set. |
|
untagged-value |
value |
Value to put in the field. |
- Reply Data
- (None)
- Error Data
-
Invokes a static method. The method must be member of the class
type or one of its superclasses. Access control is not enforced;
for example, private methods can be invoked.
The method invocation will occur in the specified thread. Method
invocation can occur only if the specified thread has been
suspended by an event. Method invocation is not supported when the
target VM has been suspended by the front-end.
The specified method is invoked with the arguments in the
specified argument list. The method invocation is synchronous; the
reply packet is not sent until the invoked method returns in the
target VM. The return value (possibly the void value) is included
in the reply packet. If the invoked method throws an exception, the
exception object ID is set in the reply packet; otherwise, the
exception object ID is null.
For primitive arguments, the argument value's type must match
the argument's type exactly. For object arguments, there must exist
a widening reference conversion from the argument value's type to
the argument's type and the argument's type must be loaded.
By default, all threads in the target VM are resumed while the
method is being invoked if they were previously suspended by an
event or by command. This is done to prevent the deadlocks that
will occur if any of the threads own monitors that will be needed
by the invoked method. It is possible that breakpoints or other
events might occur during the invocation. Note, however, that this
implicit resume acts exactly like the ThreadReference resume
command, so if the thread's suspend count is greater than 1, it
will remain in a suspended state during the invocation. By default,
when the invocation completes, all threads in the target VM are
suspended, regardless their state before the invocation.
The resumption of other threads during the invoke can be
prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the
options
field; however, there is no protection against
or recovery from the deadlocks described above, so this option
should be used with great caution. Only the specified thread will
be resumed (as described for all threads above). Upon completion of
a single threaded invoke, the invoking thread will be suspended
once again. Note that any threads started during the single
threaded invocation will not be suspended when the invocation
completes.
If the target VM is disconnected during the invoke (for example,
through the VirtualMachine dispose command) the method invocation
continues.
- Out Data
-
|
|
|
|
|
|
|
classID |
clazz |
The class type ID. |
threadID |
thread |
The thread in which to invoke. |
methodID |
methodID |
The method to invoke. |
int |
arguments |
 |
Repeated arguments times: |
|
value |
arg |
The argument value. |
int |
options |
Invocation options |
- Reply Data
-
|
|
|
|
|
|
|
value |
returnValue |
The returned value. |
tagged-objectID |
exception |
The thrown exception. |
- Error Data
-
Creates a new object of this type, invoking the specified
constructor. The constructor method ID must be a member of the
class type.
Instance creation will occur in the specified thread. Instance
creation can occur only if the specified thread has been suspended
by an event. Method invocation is not supported when the target VM
has been suspended by the front-end.
The specified constructor is invoked with the arguments in the
specified argument list. The constructor invocation is synchronous;
the reply packet is not sent until the invoked method returns in
the target VM. The return value (possibly the void value) is
included in the reply packet. If the constructor throws an
exception, the exception object ID is set in the reply packet;
otherwise, the exception object ID is null.
For primitive arguments, the argument value's type must match
the argument's type exactly. For object arguments, there must exist
a widening reference conversion from the argument value's type to
the argument's type and the argument's type must be loaded.
By default, all threads in the target VM are resumed while the
method is being invoked if they were previously suspended by an
event or by command. This is done to prevent the deadlocks that
will occur if any of the threads own monitors that will be needed
by the invoked method. It is possible that breakpoints or other
events might occur during the invocation. Note, however, that this
implicit resume acts exactly like the ThreadReference resume
command, so if the thread's suspend count is greater than 1, it
will remain in a suspended state during the invocation. By default,
when the invocation completes, all threads in the target VM are
suspended, regardless their state before the invocation.
The resumption of other threads during the invoke can be
prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the
options
field; however, there is no protection against
or recovery from the deadlocks described above, so this option
should be used with great caution. Only the specified thread will
be resumed (as described for all threads above). Upon completion of
a single threaded invoke, the invoking thread will be suspended
once again. Note that any threads started during the single
threaded invocation will not be suspended when the invocation
completes.
If the target VM is disconnected during the invoke (for example,
through the VirtualMachine dispose command) the method invocation
continues.
- Out Data
-
|
|
|
|
|
|
|
classID |
clazz |
The class type ID. |
threadID |
thread |
The thread in which to invoke the constructor. |
methodID |
methodID |
The constructor to invoke. |
int |
arguments |
 |
Repeated arguments times: |
|
value |
arg |
The argument value. |
int |
options |
Constructor invocation options |
- Reply Data
-
|
|
|
|
|
|
|
tagged-objectID |
newObject |
The newly created object, or null if the constructor threw an
exception. |
tagged-objectID |
exception |
The thrown exception, if any; otherwise, null. |
- Error Data
-
Creates a new array object of this type with a given length.
- Out Data
-
|
|
|
|
|
|
|
arrayTypeID |
arrType |
The array type of the new instance. |
int |
length |
The length of the array. |
- Reply Data
-
|
|
|
|
|
|
|
tagged-objectID |
newArray |
The newly created array object. Â |
- Error Data
-
Invokes a static method. The method must not be a static
initializer. The method must be a member of the interface type.
Since JDWP version 1.8
The method invocation will occur in the specified thread. Method
invocation can occur only if the specified thread has been
suspended by an event. Method invocation is not supported when the
target VM has been suspended by the front-end.
The specified method is invoked with the arguments in the
specified argument list. The method invocation is synchronous; the
reply packet is not sent until the invoked method returns in the
target VM. The return value (possibly the void value) is included
in the reply packet. If the invoked method throws an exception, the
exception object ID is set in the reply packet; otherwise, the
exception object ID is null.
For primitive arguments, the argument value's type must match
the argument's type exactly. For object arguments, there must exist
a widening reference conversion from the argument value's type to
the argument's type and the argument's type must be loaded.
By default, all threads in the target VM are resumed while the
method is being invoked if they were previously suspended by an
event or by a command. This is done to prevent the deadlocks that
will occur if any of the threads own monitors that will be needed
by the invoked method. It is possible that breakpoints or other
events might occur during the invocation. Note, however, that this
implicit resume acts exactly like the ThreadReference resume
command, so if the thread's suspend count is greater than 1, it
will remain in a suspended state during the invocation. By default,
when the invocation completes, all threads in the target VM are
suspended, regardless their state before the invocation.
The resumption of other threads during the invoke can be
prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the
options
field; however, there is no protection against
or recovery from the deadlocks described above, so this option
should be used with great caution. Only the specified thread will
be resumed (as described for all threads above). Upon completion of
a single threaded invoke, the invoking thread will be suspended
once again. Note that any threads started during the single
threaded invocation will not be suspended when the invocation
completes.
If the target VM is disconnected during the invoke (for example,
through the VirtualMachine dispose command) the method invocation
continues.
- Out Data
-
|
|
|
|
|
|
|
interfaceID |
clazz |
The interface type ID. |
threadID |
thread |
The thread in which to invoke. |
methodID |
methodID |
The method to invoke. |
int |
arguments |
 |
Repeated arguments times: |
|
value |
arg |
The argument value. |
int |
options |
Invocation options |
- Reply Data
-
|
|
|
|
|
|
|
value |
returnValue |
The returned value. |
tagged-objectID |
exception |
The thrown exception. |
- Error Data
-
Returns line number information for the method, if present. The
line table maps source line numbers to the initial code index of
the line. The line table is ordered by code index (from lowest to
highest). The line number information is constant unless a new
class definition is installed using RedefineClasses.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The class. |
methodID |
methodID |
The method. |
- Reply Data
-
|
|
|
|
|
|
|
long |
start |
Lowest valid code index for the method, >=0, or -1 if the
method is native  |
long |
end |
Highest valid code index for the method, >=0, or -1 if the
method is native |
int |
lines |
The number of entries in the line table for this
method. |
Repeated lines times: |
|
long |
lineCodeIndex |
Initial code index of the line, start <= lineCodeIndex <
end |
|
int |
lineNumber |
Line number. |
- Error Data
-
Returns variable information for the method. The variable table
includes arguments and locals declared within the method. For
instance methods, the "this" reference is included in the table.
Also, synthetic variables may be present.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The class. |
methodID |
methodID |
The method. |
- Reply Data
-
|
|
|
|
|
|
|
int |
argCnt |
The number of words in the frame used by arguments. Eight-byte
arguments use two words; all others use one. Â |
int |
slots |
The number of variables. |
Repeated slots times: |
|
long |
codeIndex |
First code index at which the variable is visible (unsigned).
Used in conjunction with length . The variable can be
get or set only when the current codeIndex <=
current frame code index < codeIndex + length
 |
|
string |
name |
The variable's name. |
|
string |
signature |
The variable type's JNI signature. |
|
int |
length |
Unsigned value used in conjunction with codeIndex .
The variable can be get or set only when the current
codeIndex <= current frame code index <
code index + length  |
|
int |
slot |
The local variable's index in its frame |
- Error Data
-
Retrieve the method's bytecodes as defined in The
Javaâ„¢ Virtual Machine Specification.
Requires canGetBytecodes capability - see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The class. |
methodID |
methodID |
The method. |
- Reply Data
-
|
|
|
|
|
|
|
int |
bytes |
 |
Repeated bytes times: |
|
byte |
bytecode |
A Java bytecode. |
- Error Data
-
Determine if this method is obsolete. A method is obsolete if it
has been replaced by a non-equivalent method using the RedefineClasses command.
The original and redefined methods are considered equivalent if
their bytecodes are the same except for indices into the constant
pool and the referenced constants are equal.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The class. |
methodID |
methodID |
The method. |
- Reply Data
-
|
|
|
|
|
|
|
boolean |
isObsolete |
true if this method has been replacedby a non-equivalent method
usingthe RedefineClasses command. |
- Error Data
-
Returns variable information for the method, including generic
signatures for the variables. The variable table includes arguments
and locals declared within the method. For instance methods, the
"this" reference is included in the table. Also, synthetic
variables may be present. Generic signatures are described in the
signature attribute section in The Javaâ„¢
Virtual Machine Specification. Since JDWP version 1.5.
- Out Data
-
|
|
|
|
|
|
|
referenceTypeID |
refType |
The class. |
methodID |
methodID |
The method. |
- Reply Data
-
|
|
|
|
|
|
|
int |
argCnt |
The number of words in the frame used by arguments. Eight-byte
arguments use two words; all others use one. Â |
int |
slots |
The number of variables. |
Repeated slots times: |
|
long |
codeIndex |
First code index at which the variable is visible (unsigned).
Used in conjunction with length . The variable can be
get or set only when the current codeIndex <=
current frame code index < codeIndex + length
 |
|
string |
name |
The variable's name. |
|
string |
signature |
The variable type's JNI signature. |
|
string |
genericSignature |
The variable type's generic signature or an empty string if
there is none. |
|
int |
length |
Unsigned value used in conjunction with codeIndex .
The variable can be get or set only when the current
codeIndex <= current frame code index <
code index + length  |
|
int |
slot |
The local variable's index in its frame |
- Error Data
-
Returns the runtime type of the object. The runtime type will be
a class or an array.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
- Reply Data
-
|
|
|
|
|
|
|
byte |
refTypeTag |
Kind of following reference type.
 |
referenceTypeID |
typeID |
The runtime reference type. |
- Error Data
-
INVALID_OBJECT |
If this reference type has been unloaded and garbage
collected. |
VM_DEAD |
The virtual machine is not running. |
Returns the value of one or more instance fields. Each field
must be member of the object's type or one of its superclasses,
superinterfaces, or implemented interfaces. Access control is not
enforced; for example, the values of private fields can be
obtained.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
int |
fields |
The number of values to get |
Repeated fields times: |
|
fieldID |
fieldID |
Field to get. |
- Reply Data
-
|
|
|
|
|
|
|
int |
values |
The number of values returned, always equal to 'fields', the
number of values to get. Field values are ordered in the reply in
the same order as corresponding fieldIDs in the
command. |
Repeated values times: |
|
value |
value |
The field value |
- Error Data
-
Sets the value of one or more instance fields. Each field must
be member of the object's type or one of its superclasses,
superinterfaces, or implemented interfaces. Access control is not
enforced; for example, the values of private fields can be set. For
primitive values, the value's type must match the field's type
exactly. For object values, there must be a widening reference
conversion from the value's type to thefield's type and the field's
type must be loaded.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
int |
values |
The number of fields to set. |
Repeated values times: |
|
fieldID |
fieldID |
Field to set. |
|
untagged-value |
value |
Value to put in the field. |
- Reply Data
- (None)
- Error Data
-
Returns monitor information for an object. All threads int the
VM must be suspended.Requires canGetMonitorInfo capability - see
CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
- Reply Data
-
|
|
|
|
|
|
|
threadID |
owner |
The monitor owner, or null if it is not currently
owned. |
int |
entryCount |
The number of times the monitor has been
entered. |
int |
waiters |
The number of threads that are waiting for the monitor 0 if
there is no current owner |
Repeated waiters times: |
|
threadID |
thread |
A thread waiting for this monitor. |
- Error Data
-
INVALID_OBJECT |
If this reference type has been unloaded and garbage
collected. |
NOT_IMPLEMENTED |
The functionality is not implemented in this virtual
machine. |
VM_DEAD |
The virtual machine is not running. |
Invokes a instance method. The method must be member of the
object's type or one of its superclasses, superinterfaces, or
implemented interfaces. Access control is not enforced; for
example, private methods can be invoked.
The method invocation will occur in the specified thread. Method
invocation can occur only if the specified thread has been
suspended by an event. Method invocation is not supported when the
target VM has been suspended by the front-end.
The specified method is invoked with the arguments in the
specified argument list. The method invocation is synchronous; the
reply packet is not sent until the invoked method returns in the
target VM. The return value (possibly the void value) is included
in the reply packet. If the invoked method throws an exception, the
exception object ID is set in the reply packet; otherwise, the
exception object ID is null.
For primitive arguments, the argument value's type must match
the argument's type exactly. For object arguments, there must be a
widening reference conversion from the argument value's type to the
argument's type and the argument's type must be loaded.
By default, all threads in the target VM are resumed while the
method is being invoked if they were previously suspended by an
event or by a command. This is done to prevent the deadlocks that
will occur if any of the threads own monitors that will be needed
by the invoked method. It is possible that breakpoints or other
events might occur during the invocation. Note, however, that this
implicit resume acts exactly like the ThreadReference resume
command, so if the thread's suspend count is greater than 1, it
will remain in a suspended state during the invocation. By default,
when the invocation completes, all threads in the target VM are
suspended, regardless their state before the invocation.
The resumption of other threads during the invoke can be
prevented by specifying the INVOKE_SINGLE_THREADED bit flag in the
options
field; however, there is no protection against
or recovery from the deadlocks described above, so this option
should be used with great caution. Only the specified thread will
be resumed (as described for all threads above). Upon completion of
a single threaded invoke, the invoking thread will be suspended
once again. Note that any threads started during the single
threaded invocation will not be suspended when the invocation
completes.
If the target VM is disconnected during the invoke (for example,
through the VirtualMachine dispose command) the method invocation
continues.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
threadID |
thread |
The thread in which to invoke. |
classID |
clazz |
The class type. |
methodID |
methodID |
The method to invoke. |
int |
arguments |
The number of arguments. |
Repeated arguments times: |
|
value |
arg |
The argument value. |
int |
options |
Invocation options |
- Reply Data
-
|
|
|
|
|
|
|
value |
returnValue |
The returned value, or null if an exception is
thrown. |
tagged-objectID |
exception |
The thrown exception, if any. |
- Error Data
-
INVALID_OBJECT |
If this reference type has been unloaded and garbage
collected. |
INVALID_CLASS |
clazz is not the ID of a reference type. |
INVALID_METHODID |
methodID is not the ID of an instance method in this object's
type or one of its superclasses, superinterfaces, or implemented
interfaces. |
INVALID_THREAD |
Passed thread is null, is not a valid thread or has
exited. |
THREAD_NOT_SUSPENDED |
If the specified thread has not been suspended by an
event. |
VM_DEAD |
The virtual machine is not running. |
Prevents garbage collection for the given object. By default all
objects in back-end replies may be collected at any time the target
VM is running. A call to this command guarantees that the object
will not be collected. The EnableCollection
command can be used to allow collection once again.
Note that while the target VM is suspended, no garbage
collection will occur because all threads are suspended. The
typical examination of variables, fields, and arrays during the
suspension is safe without explicitly disabling garbage
collection.
This method should be used sparingly, as it alters the pattern
of garbage collection in the target VM and, consequently, may
result in application behavior under the debugger that differs from
its non-debugged behavior.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
- Reply Data
- (None)
- Error Data
-
INVALID_OBJECT |
If this reference type has been unloaded and garbage
collected. |
VM_DEAD |
The virtual machine is not running. |
Permits garbage collection for this object. By default all
objects returned by JDWP may become unreachable in the target VM,
and hence may be garbage collected. A call to this command is
necessary only if garbage collection was previously disabled with
the DisableCollection
command.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
- Reply Data
- (None)
- Error Data
-
VM_DEAD |
The virtual machine is not running. |
Determines whether an object has been garbage collected in the
target VM.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
- Reply Data
-
|
|
|
|
|
|
|
boolean |
isCollected |
true if the object has been collected; false
otherwise |
- Error Data
-
INVALID_OBJECT |
If this reference type has been unloaded and garbage
collected. |
VM_DEAD |
The virtual machine is not running. |
Returns objects that directly reference this object. Only
objects that are reachable for the purposes of garbage collection
are returned. Note that an object can also be referenced in other
ways, such as from a local variable in a stack frame, or from a JNI
global reference. Such non-object referrers are not returned by
this command.
Since JDWP version 1.6. Requires canGetInstanceInfo capability -
see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
objectID |
object |
The object IDÂ |
int |
maxReferrers |
Maximum number of referring objects to return. Must be
non-negative. If zero, all referring objects are
returned. |
- Reply Data
-
|
|
|
|
|
|
|
int |
referringObjects |
The number of objects that follow. |
Repeated referringObjects times: |
|
tagged-objectID |
instance |
An object that references this object. |
- Error Data
-
Returns the characters contained in the string.
- Out Data
-
|
|
|
|
|
|
|
objectID |
stringObject |
The String object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
string |
stringValue |
UTF-8 representation of the string value. |
- Error Data
-
Returns the thread name.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
string |
threadName |
The thread name. |
- Error Data
-
Suspends the thread.
Unlike java.lang.Thread.suspend(), suspends of both the virtual
machine and individual threads are counted. Before a thread will
run again, it must be resumed the same number of times it has been
suspended.
Suspending single threads with command has the same dangers
java.lang.Thread.suspend(). If the suspended thread holds a monitor
needed by another running thread, deadlock is possible in the
target VM (at least until the suspended thread is resumed
again).
The suspended thread is guaranteed to remain suspended until
resumed through one of the JDI resume methods mentioned above; the
application in the target VM cannot resume the suspended thread
through {@link java.lang.Thread#resume}.
Note that this doesn't change the status of the thread (see the
ThreadStatus command.)
For example, if it was Running, it will still appear running to
other threads.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
- (None)
- Error Data
-
Resumes the execution of a given thread. If this thread was not
previously suspended by the front-end, calling this command has no
effect. Otherwise, the count of pending suspends on this thread is
decremented. If it is decremented to 0, the thread will continue to
execute.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
- (None)
- Error Data
-
Returns the current status of a thread. The thread status reply
indicates the thread status the last time it was running. the
suspend status provides information on the thread's suspension, if
any.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
- Error Data
-
Returns the thread group that contains a given thread.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
threadGroupID |
group |
The thread group of this thread. Â |
- Error Data
-
Returns the current call stack of a suspended thread. The
sequence of frames starts with the currently executing frame,
followed by its caller, and so on. The thread must be suspended,
and the returned frameID is valid only while the thread is
suspended.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
int |
startFrame |
The index of the first frame to retrieve. |
int |
length |
The count of frames to retrieve (-1 means all remaining).
 |
- Reply Data
-
|
|
|
|
|
|
|
int |
frames |
The number of frames retreived |
Repeated frames times: |
|
frameID |
frameID |
The ID of this frame. Â |
|
location |
location |
The current location of this frame |
- Error Data
-
Returns the count of frames on this thread's stack. The thread
must be suspended, and the returned count is valid only while the
thread is suspended. Returns JDWP.Error.errorThreadNotSuspended if
not suspended.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
frameCount |
The count of frames on this thread's stack. Â |
- Error Data
-
Returns the objects whose monitors have been entered by this
thread. The thread must be suspended, and the returned information
is relevant only while the thread is suspended. Requires
canGetOwnedMonitorInfo capability - see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
owned |
The number of owned monitors |
Repeated owned times: |
|
tagged-objectID |
monitor |
An owned monitor |
- Error Data
-
Returns the object, if any, for which this thread is waiting.
The thread may be waiting to enter a monitor, or it may be waiting,
via the java.lang.Object.wait method, for another thread to invoke
the notify method. The thread must be suspended, and the returned
information is relevant only while the thread is suspended.
Requires canGetCurrentContendedMonitor capability - see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
tagged-objectID |
monitor |
The contended monitor, or null if there is no current contended
monitor. Â |
- Error Data
-
Stops the thread with an asynchronous exception, as if done by
java.lang.Thread.stop
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
objectID |
throwable |
Asynchronous exception. This object must be an instance of
java.lang.Throwable or a subclass |
- Reply Data
- (None)
- Error Data
-
INVALID_THREAD |
Passed thread is null, is not a valid thread or has
exited. |
INVALID_OBJECT |
If thread is not a known ID or the asynchronous exception has
been garbage collected. |
VM_DEAD |
The virtual machine is not running. |
Interrupt the thread, as if done by
java.lang.Thread.interrupt
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
- (None)
- Error Data
-
Get the suspend count for this thread. The suspend count is the
number of times the thread has been suspended through the
thread-level or VM-level suspend commands without a corresponding
resume
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
suspendCount |
The number of outstanding suspends of this thread.
 |
- Error Data
-
(13)
Returns monitor objects owned by the thread, along with stack
depth at which the monitor was acquired. Returns stack depth of -1
if the implementation cannot determine the stack depth (e.g., for
monitors acquired by JNI MonitorEnter).The thread must be
suspended, and the returned information is relevant only while the
thread is suspended. Requires canGetMonitorFrameInfo capability -
see CapabilitiesNew.
Since JDWP version 1.6.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
owned |
The number of owned monitors |
Repeated owned times: |
|
tagged-objectID |
monitor |
An owned monitor |
|
int |
stack_depth |
Stack depth location where monitor was
acquired |
- Error Data
-
Force a method to return before it reaches a return
statement.
The method which will return early is referred to as the called
method. The called method is the current method (as defined by the
Frames section in The Javaâ„¢ Virtual Machine
Specification) for the specified thread at the time this
command is received.
The specified thread must be suspended. The return occurs when
execution of Java programming language code is resumed on this
thread. Between sending this command and resumption of thread
execution, the state of the stack is undefined.
No further instructions are executed in the called method.
Specifically, finally blocks are not executed. Note: this can cause
inconsistent states in the application.
A lock acquired by calling the called method (if it is a
synchronized method) and locks acquired by entering synchronized
blocks within the called method are released. Note: this does not
apply to JNI locks or java.util.concurrent.locks locks.
Events, such as MethodExit, are generated as they would be in a
normal return.
The called method must be a non-native Java programming language
method. Forcing return on a thread with only one frame on the stack
causes the thread to exit when resumed.
For void methods, the value must be a void value. For methods
that return primitive values, the value's type must match the
return type exactly. For object values, there must be a widening
reference conversion from the value's type to the return type type
and the return type must be loaded.
Since JDWP version 1.6. Requires canForceEarlyReturn capability
- see CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
value |
value |
The value to return. Â |
- Reply Data
- (None)
- Error Data
-
INVALID_THREAD |
Passed thread is null, is not a valid thread or has
exited. |
INVALID_OBJECT |
Thread or value is not a known ID. |
THREAD_NOT_SUSPENDED |
If the specified thread has not been suspended by an
event. |
THREAD_NOT_ALIVE |
Thread has not been started or is now dead. |
OPAQUE_FRAME |
Attempted to return early from a frame corresponding to a
native method. Or the implementation is unable to provide this
functionality on this frame. |
NO_MORE_FRAMES |
There are no more Java or JNI frames on the call
stack. |
NOT_IMPLEMENTED |
The functionality is not implemented in this virtual
machine. |
TYPE_MISMATCH |
Value is not an appropriate type for the return value of the
method. |
VM_DEAD |
The virtual machine is not running. |
Returns the thread group name.
- Out Data
-
|
|
|
|
|
|
|
threadGroupID |
group |
The thread group object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
string |
groupName |
The thread group's name. |
- Error Data
-
Returns the thread group, if any, which contains a given thread
group.
- Out Data
-
|
|
|
|
|
|
|
threadGroupID |
group |
The thread group object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
threadGroupID |
parentGroup |
The parent thread group object, or null if the given thread
group is a top-level thread group |
- Error Data
-
Returns the live threads and active thread groups directly
contained in this thread group. Threads and thread groups in child
thread groups are not included. A thread is alive if it has been
started and has not yet been stopped. See java.lang.ThreadGroup
for information about active ThreadGroups.
- Out Data
-
|
|
|
|
|
|
|
threadGroupID |
group |
The thread group object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
childThreads |
The number of live child threads. Â |
Repeated childThreads times: |
|
threadID |
childThread |
A direct child thread ID. Â |
int |
childGroups |
The number of active child thread groups. Â |
Repeated childGroups times: |
|
threadGroupID |
childGroup |
A direct child thread group ID. Â |
- Error Data
-
Returns the number of components in a given array.
- Out Data
-
|
|
|
|
|
|
|
arrayID |
arrayObject |
The array object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
arrayLength |
The length of the array. |
- Error Data
-
Returns a range of array components. The specified range must be
within the bounds of the array.
- Out Data
-
|
|
|
|
|
|
|
arrayID |
arrayObject |
The array object ID. Â |
int |
firstIndex |
The first index to retrieve. |
int |
length |
The number of components to retrieve. |
- Reply Data
-
|
|
|
|
|
|
|
arrayregion |
values |
The retrieved values. If the values are objects, they are
tagged-values; otherwise, they are untagged-values |
- Error Data
-
Sets a range of array components. The specified range must be
within the bounds of the array. For primitive values, each value's
type must match the array component type exactly. For object
values, there must be a widening reference conversion from the
value's type to thearray component type and the array component
type must be loaded.
- Out Data
-
|
|
|
|
|
|
|
arrayID |
arrayObject |
The array object ID. Â |
int |
firstIndex |
The first index to set. |
int |
values |
The number of values to set. Â |
Repeated values times: |
|
untagged-value |
value |
A value to set. Â |
- Reply Data
- (None)
- Error Data
-
Returns a list of all classes which this class loader has been
requested to load. This class loader is considered to be an
initiating class loader for each class in the returned list.
The list contains each reference type defined by this loader and
any types for which loading was delegated by this class loader to
another class loader.
The visible class list has useful properties with respect to the
type namespace. A particular type name will occur at most once in
the list. Each field or variable declared with that type name in a
class defined by this class loader must be resolved to that single
type.
No ordering of the returned list is guaranteed.
- Out Data
-
|
|
|
|
|
|
|
classLoaderID |
classLoaderObject |
The class loader object ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
classes |
The number of visible classes. Â |
Repeated classes times: |
|
byte |
refTypeTag |
Kind of following reference type.
 |
|
referenceTypeID |
typeID |
A class visible to this class loader. |
- Error Data
-
Set an event request. When the event described by this request
occurs, an event is sent from the target
VM. If an event occurs that has not been requested then it is not
sent from the target VM. The two exceptions to this are the VM
Start Event and the VM Death Event which are automatically
generated events - see Composite
Command for further details.
- Out Data
-
|
|
|
|
|
|
|
byte |
eventKind |
Event kind to request. See JDWP.EventKind for a complete list of events
that can be requested; some events may require a capability in
order to be requested. Â |
byte |
suspendPolicy |
What threads are suspended when this event occurs? Note that
the order of events and command replies accurately reflects the
order in which threads are suspended and resumed. For example, if a
VM-wide resume is
processed before an event occurs which suspends the VM, the reply
to the resume command will be written to the transport before the
suspending event. |
int |
modifiers |
Constraints used to control the number of generated
events.Modifiers specify additional tests that an event must
satisfy before it is placed in the event queue. Events are filtered
by applying each modifier to an event in the order they are
specified in this collection Only events that satisfy all modifiers
are reported. A value of 0 means there are no modifiers in the
request.
Filtering can improve debugger performance dramatically
byreducing the amount of event traffic sent from the target VM to
the debugger VM. Â
|
Repeated modifiers times: |
|
byte |
modKind |
Modifier kind |
|
Case Count - if modKind is 1: |
Limit the requested event to be reported at most once after a
given number of occurrences. The event is not reported the first
count - 1 times this filter is reached. To request a
one-off event, call this method with a count of 1.
Once the count reaches 0, any subsequent filters in this request
are applied. If none of those filters cause the event to be
suppressed, the event is reported. Otherwise, the event is not
reported. In either case subsequent events are never reported for
this request. This modifier can be used with any event
kind.Â
|
|
int |
count |
Count before event. One for one-off. |
|
Case Conditional - if modKind is 2: |
Conditional on expression |
|
int |
exprID |
For the future |
|
Case ThreadOnly - if modKind is 3: |
Restricts reported events to those in the given thread. This
modifier can be used with any event kind except for class unload.
 |
|
threadID |
thread |
Required thread |
|
Case ClassOnly - if modKind is 4: |
For class prepare events, restricts the events generated by
this request to be the preparation of the given reference type and
any subtypes. For monitor wait and waited events, restricts the
events generated by this request to those whose monitor object is
of the given reference type or any of its subtypes. For other
events, restricts the events generated by this request to those
whose location is in the given reference type or any of its
subtypes. An event will be generated for any location in a
reference type that can be safely cast to the given reference type.
This modifier can be used with any event kind except class unload,
thread start, and thread end. Â |
|
referenceTypeID |
clazz |
Required class |
|
Case ClassMatch - if modKind is 5: |
Restricts reported events to those for classes whose name
matches the given restricted regular expression. For class prepare
events, the prepared class name is matched. For class unload
events, the unloaded class name is matched. For monitor wait and
waited events, the name of the class of the monitor object is
matched. For other events, the class name of the event's location
is matched. This modifier can be used with any event kind except
thread start and thread end. Â |
|
string |
classPattern |
Required class pattern. Matches are limited to exact matches of
the given class pattern and matches of patterns that begin or end
with '*'; for example, "*.Foo" or "java.*". Â |
|
Case ClassExclude - if modKind is 6: |
Restricts reported events to those for classes whose name does
not match the given restricted regular expression. For class
prepare events, the prepared class name is matched. For class
unload events, the unloaded class name is matched. For monitor wait
and waited events, the name of the class of the monitor object is
matched. For other events, the class name of the event's location
is matched. This modifier can be used with any event kind except
thread start and thread end. Â |
|
string |
classPattern |
Disallowed class pattern. Matches are limited to exact matches
of the given class pattern and matches of patterns that begin or
end with '*'; for example, "*.Foo" or "java.*". Â |
|
Case LocationOnly - if modKind is 7: |
Restricts reported events to those that occur at the given
location. This modifier can be used with breakpoint, field access,
field modification, step, and exception event kinds.
 |
|
location |
loc |
Required location |
|
Case ExceptionOnly - if modKind is 8: |
Restricts reported exceptions by their class and whether they
are caught or uncaught. This modifier can be used with exception
event kinds only. Â |
|
referenceTypeID |
exceptionOrNull |
Exception to report. Null (0) means report exceptions of all
types. A non-null type restricts the reported exception events to
exceptions of the given type or any of its subtypes.
 |
|
boolean |
caught |
Report caught exceptions |
|
boolean |
uncaught |
Report uncaught exceptions. Note that it is not always possible
to determine whether an exception is caught or uncaught at the time
it is thrown. See the exception event catch location under composite events for more information.
 |
|
Case FieldOnly - if modKind is 9: |
Restricts reported events to those that occur for a given
field. This modifier can be used with field access and field
modification event kinds only. Â |
|
referenceTypeID |
declaring |
Type in which field is declared. |
|
fieldID |
fieldID |
Required field |
|
Case Step - if modKind is 10: |
Restricts reported step events to those which satisfy depth and
size constraints. This modifier can be used with step event kinds
only. Â |
|
threadID |
thread |
Thread in which to step |
|
int |
size |
size of each step. See JDWP.StepSize |
|
int |
depth |
relative call stack limit. See JDWP.StepDepth |
|
Case InstanceOnly - if modKind is 11: |
Restricts reported events to those whose active 'this' object
is the given object. Match value is the null object for static
methods. This modifier can be used with any event kind except class
prepare, class unload, thread start, and thread end. Introduced in
JDWP version 1.4. |
|
objectID |
instance |
Required 'this' object |
|
Case SourceNameMatch - if modKind is
12: |
Restricts reported class prepare events to those for reference
types which have a source name which matches the given restricted
regular expression. The source names are determined by the
reference type's SourceDebugExtension.
This modifier can only be used with class prepare events. Since
JDWP version 1.6. Requires the canUseSourceNameFilters capability -
see CapabilitiesNew. |
|
string |
sourceNamePattern |
Required source name pattern. Matches are limited to exact
matches of the given pattern and matches of patterns that begin or
end with '*'; for example, "*.Foo" or "java.*". Â |
- Reply Data
-
|
|
|
|
|
|
|
int |
requestID |
ID of created request |
- Error Data
-
Clear an event request. See JDWP.EventKind for a complete list of events
that can be cleared. Only the event request matching the specified
event kind and requestID is cleared. If there isn't a matching
event request the command is a no-op and does not result in an
error. Automatically generated events do not have a corresponding
event request and may not be cleared using this command.
- Out Data
-
|
|
|
|
|
|
|
byte |
eventKind |
Event kind to clear |
int |
requestID |
ID of request to clear |
- Reply Data
- (None)
- Error Data
-
Removes all set breakpoints, a no-op if there are no breakpoints
set.
- Out Data
- (None)
- Reply Data
- (None)
- Error Data
-
VM_DEAD |
The virtual machine is not running. |
Returns the value of one or more local variables in a given
frame. Each variable must be visible at the frame's code index.
Even if local variable information is not available, values can be
retrieved if the front-end is able to determine the correct local
variable index. (Typically, this index can be determined for method
arguments from the method signature without access to the local
variable table information.)
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The frame's thread. Â |
frameID |
frame |
The frame ID. Â |
int |
slots |
The number of values to get. Â |
Repeated slots times: |
|
int |
slot |
The local variable's index in the frame. Â |
|
byte |
sigbyte |
A tag identifying the type of the
variable  |
- Reply Data
-
|
|
|
|
|
|
|
int |
values |
The number of values retrieved, always equal to slots, the
number of values to get. |
Repeated values times: |
|
value |
slotValue |
The value of the local variable. Â |
- Error Data
-
Sets the value of one or more local variables. Each variable
must be visible at the current frame code index. For primitive
values, the value's type must match the variable's type exactly.
For object values, there must be a widening reference conversion
from the value's type to thevariable's type and the variable's type
must be loaded.
Even if local variable information is not available, values can
be set, if the front-end is able to determine the correct local
variable index. (Typically, thisindex can be determined for method
arguments from the method signature without access to the local
variable table information.)
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The frame's thread. Â |
frameID |
frame |
The frame ID. Â |
int |
slotValues |
The number of values to set. Â |
Repeated slotValues times: |
|
int |
slot |
The slot ID. Â |
|
value |
slotValue |
The value to set. Â |
- Reply Data
- (None)
- Error Data
-
Returns the value of the 'this' reference for this frame. If the
frame's method is static or native, the reply will contain the null
object reference.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The frame's thread. Â |
frameID |
frame |
The frame ID. Â |
- Reply Data
-
|
|
|
|
|
|
|
tagged-objectID |
objectThis |
The 'this' object for this frame. Â |
- Error Data
-
Pop the top-most stack frames of the thread stack, up to, and
including 'frame'. The thread must be suspended to perform this
command. The top-most stack frames are discarded and the stack
frame previous to 'frame' becomes the current frame. The operand
stack is restored -- the argument values are added back and if the
invoke was not invokestatic
, objectref
is
added back as well. The Java virtual machine program counter is
restored to the opcode of the invoke instruction.
Since JDWP version 1.4. Requires canPopFrames capability - see
CapabilitiesNew.
- Out Data
-
|
|
|
|
|
|
|
threadID |
thread |
The thread object ID. Â |
frameID |
frame |
The frame ID. Â |
- Reply Data
- (None)
- Error Data
-
Returns the reference type reflected by this class object.
- Out Data
-
|
|
|
|
|
|
|
classObjectID |
classObject |
The class object. Â |
- Reply Data
-
|
|
|
|
|
|
|
byte |
refTypeTag |
Kind of following reference type.
 |
referenceTypeID |
typeID |
reflected reference type |
- Error Data
-
INVALID_OBJECT |
If this reference type has been unloaded and garbage
collected. |
VM_DEAD |
The virtual machine is not running. |
Returns the name of this
module.
Since JDWP version 9.
- Out Data
-
|
|
|
|
|
|
|
moduleID |
module |
This
module. |
- Reply Data
-
|
|
|
|
|
|
|
string |
name |
The module's
name. |
- Error Data
-
Returns the class loader of this
module.
Since JDWP version 9.
- Out Data
-
|
|
|
|
|
|
|
moduleID |
module |
This
module. |
- Reply Data
-
|
|
|
|
|
|
|
classLoaderID |
classLoader |
The module's class
loader. |
- Error Data
-
Several events may occur at a given time in the target VM. For
example, there may be more than one breakpoint request for a given
location or you might single step to the same location as a
breakpoint request. These events are delivered together as a
composite event. For uniformity, a composite event is always used
to deliver events, even if there is only one event to report.
The events that are grouped in a composite event are restricted
in the following ways:
- Only with other thread start events for the same thread:
- Only with other thread death events for the same thread:
- Only with other class prepare events for the same class:
- Only with other class unload events for the same class:
- Only with other access watchpoint events for the same field
access:
- Only with other modification watchpoint events for the same
field modification:
- Modification Watchpoint Event
- Only with other Monitor contended enter events for the same
monitor object:
- Monitor Contended Enter Event
- Only with other Monitor contended entered events for the same
monitor object:
- Monitor Contended Entered Event
- Only with other Monitor wait events for the same monitor
object:
- Only with other Monitor waited events for the same monitor
object:
- Only with other ExceptionEvents for the same exception
occurrance:
- Only with other members of this group, at the same location and
in the same thread:
- Breakpoint Event
- Step Event
- Method Entry Event
- Method Exit Event
The VM Start Event and VM Death Event are automatically
generated events. This means they do not need to be requested using
the EventRequest.Set command.
The VM Start event signals the completion of VM initialization. The
VM Death event signals the termination of the VM.If there is a
debugger connected at the time when an automatically generated
event occurs it is sent from the target VM. Automatically generated
events may also be requested using the EventRequest.Set command and
thus multiple events of the same event kind will be sent from the
target VM when an event occurs.Automatically generated events are
sent with the requestID field in the Event Data set to 0. The value
of the suspendPolicy field in the Event Data depends on the event.
For the automatically generated VM Start Event the value of
suspendPolicy is not defined and is therefore implementation or
configuration specific. In the Sun implementation, for example, the
suspendPolicy is specified as an option to the JDWP agent at
launch-time.The automatically generated VM Death Event will have
the suspendPolicy set to NONE.
- Event Data
-
|
|
|
|
|
|
|
byte |
suspendPolicy |
Which threads where suspended by this composite
event? |
int |
events |
Events in set. |
Repeated events times: |
|
byte |
eventKind |
Event kind selector |
|
Case VMStart - if eventKind is
JDWP.EventKind.VM_START: |
Notification of initialization of a target VM. This event is
received before the main thread is started and before any
application code has been executed. Before this event occurs a
significant amount of system code has executed and a number of
system classes have been loaded. This event is always generated by
the target VM, even if not explicitly requested. |
|
int |
requestID |
Request that generated event (or 0 if this event is
automatically generated. |
|
threadID |
thread |
Initial thread |
|
Case SingleStep - if eventKind is
JDWP.EventKind.SINGLE_STEP: |
Notification of step completion in the target VM. The step
event is generated before the code at its location is executed.
 |
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Stepped thread |
|
location |
location |
Location stepped to |
|
Case Breakpoint - if eventKind is
JDWP.EventKind.BREAKPOINT: |
Notification of a breakpoint in the target VM. The breakpoint
event is generated before the code at its location is executed.
 |
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which hit breakpoint |
|
location |
location |
Location hit |
|
Case MethodEntry - if eventKind is
JDWP.EventKind.METHOD_ENTRY: |
Notification of a method invocation in the target VM. This
event is generated before any code in the invoked method has
executed. Method entry events are generated for both native and
non-native methods.
In some VMs method entry events can occur for a particular
thread before its thread start event occurs if methods are called
as part of the thread's initialization. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which entered method |
|
location |
location |
The initial executable location in the method. |
|
Case MethodExit - if eventKind is
JDWP.EventKind.METHOD_EXIT: |
Notification of a method return in the target VM. This event is
generated after all code in the method has executed, but the
location of this event is the last executed location in the method.
Method exit events are generated for both native and non-native
methods. Method exit events are not generated if the method
terminates with a thrown exception. Â |
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which exited method |
|
location |
location |
Location of exit |
|
Case MethodExitWithReturnValue - if
eventKind is
JDWP.EventKind.METHOD_EXIT_WITH_RETURN_VALUE: |
Notification of a method return in the target VM. This event is
generated after all code in the method has executed, but the
location of this event is the last executed location in the method.
Method exit events are generated for both native and non-native
methods. Method exit events are not generated if the method
terminates with a thrown exception.
Since JDWP version 1.6. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which exited method |
|
location |
location |
Location of exit |
|
value |
value |
Value that will be returned by the method |
|
Case MonitorContendedEnter - if eventKind is
JDWP.EventKind.MONITOR_CONTENDED_ENTER: |
Notification that a thread in the target VM is attempting to
enter a monitor that is already acquired by another thread.
Requires canRequestMonitorEvents capability - see CapabilitiesNew.
Since JDWP version 1.6. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which is trying to enter the monitor |
|
tagged-objectID |
object |
Monitor object reference |
|
location |
location |
Location of contended monitor enter |
|
Case MonitorContendedEntered - if eventKind
is JDWP.EventKind.MONITOR_CONTENDED_ENTERED: |
Notification of a thread in the target VM is entering a monitor
after waiting for it to be released by another thread. Requires
canRequestMonitorEvents capability - see CapabilitiesNew.
Since JDWP version 1.6. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which entered monitor |
|
tagged-objectID |
object |
Monitor object reference |
|
location |
location |
Location of contended monitor enter |
|
Case MonitorWait - if eventKind is
JDWP.EventKind.MONITOR_WAIT: |
Notification of a thread about to wait on a monitor object.
Requires canRequestMonitorEvents capability - see CapabilitiesNew.
Since JDWP version 1.6. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which is about to wait |
|
tagged-objectID |
object |
Monitor object reference |
|
location |
location |
Location at which the wait will occur |
|
long |
timeout |
Thread wait time in milliseconds |
|
Case MonitorWaited - if eventKind is
JDWP.EventKind.MONITOR_WAITED: |
Notification that a thread in the target VM has finished
waiting on Requires canRequestMonitorEvents capability - see
CapabilitiesNew.
a monitor object.
Since JDWP version 1.6. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread which waited |
|
tagged-objectID |
object |
Monitor object reference |
|
location |
location |
Location at which the wait occured |
|
boolean |
timed_out |
True if timed out |
|
Case Exception - if eventKind is
JDWP.EventKind.EXCEPTION: |
Notification of an exception in the target VM. If the exception
is thrown from a non-native method, the exception event is
generated at the location where the exception is thrown. If the
exception is thrown from a native method, the exception event is
generated at the first non-native location reached after the
exception is thrown. Â |
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Thread with exception |
|
location |
location |
Location of exception throw (or first non-native location after
throw if thrown from a native method)Â |
|
tagged-objectID |
exception |
Thrown exception |
|
location |
catchLocation |
Location of catch, or 0 if not caught. An exception is
considered to be caught if, at the point of the throw, the current
location is dynamically enclosed in a try statement that handles
the exception. (See the JVM specification for details). If there is
such a try statement, the catch location is the first location in
the appropriate catch clause.
If there are native methods in the call stack at the time of the
exception, there are important restrictions to note about the
returned catch location. In such cases, it is not possible to
predict whether an exception will be handled by some native method
on the call stack. Thus, it is possible that exceptions considered
uncaught here will, in fact, be handled by a native method and not
cause termination of the target VM. Furthermore, it cannot be
assumed that the catch location returned here will ever be reached
by the throwing thread. If there is a native frame between the
current location and the catch location, the exception might be
handled and cleared in that native method instead.
Note that compilers can generate try-catch blocks in some cases
where they are not explicit in the source code; for example, the
code generated for synchronized and
finally blocks can contain implicit try-catch blocks.
If such an implicitly generated try-catch is present on the call
stack at the time of the throw, the exception will be considered
caught even though it appears to be uncaught from examination of
the source code. Â
|
|
Case ThreadStart - if eventKind is
JDWP.EventKind.THREAD_START: |
Notification of a new running thread in the target VM. The new
thread can be the result of a call to
java.lang.Thread.start or the result of attaching a
new thread to the VM though JNI. The notification is generated by
the new thread some time before its execution starts. Because of
this timing, it is possible to receive other events for the thread
before this event is received. (Notably, Method Entry Events and
Method Exit Events might occur during thread initialization. It is
also possible for the VirtualMachine AllThreads
command to return a thread before its thread start event is
received.
Note that this event gives no information about the creation of
the thread object which may have happened much earlier, depending
on the VM being debugged. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Started thread |
|
Case ThreadDeath - if eventKind is
JDWP.EventKind.THREAD_DEATH: |
Notification of a completed thread in the target VM. The
notification is generated by the dying thread before it terminates.
Because of this timing, it is possible for {@link
VirtualMachine#allThreads} to return this thread after this event
is received.
Note that this event gives no information about the lifetime of
the thread object. It may or may not be collected soon depending on
what references exist in the target VM. Â
|
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Ending thread |
|
Case ClassPrepare - if eventKind is
JDWP.EventKind.CLASS_PREPARE: |
Notification of a class prepare in the target VM. See the JVM
specification for a definition of class preparation. Class prepare
events are not generated for primtiive classes (for example,
java.lang.Integer.TYPE). Â |
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Preparing thread. In rare cases, this event may occur in a
debugger system thread within the target VM. Debugger threads take
precautions to prevent these events, but they cannot be avoided
under some conditions, especially for some subclasses of
java.lang.Error. If the event was generated by a debugger system
thread, the value returned by this method is null, and if the
requested suspend policy for the
event was EVENT_THREAD all threads will be suspended instead, and
the composite event's suspend policy will reflect this change.
Note that the discussion above does not apply to system threads
created by the target VM during its normal (non-debug) operation.
Â
|
|
byte |
refTypeTag |
Kind of reference type. See JDWP.TypeTag |
|
referenceTypeID |
typeID |
Type being prepared |
|
string |
signature |
Type signature |
|
int |
status |
Status of type. See JDWP.ClassStatus |
|
Case ClassUnload - if eventKind is
JDWP.EventKind.CLASS_UNLOAD: |
Notification of a class unload in the target VM.
There are severe constraints on the debugger back-end during
garbage collection, so unload information is greatly limited.
Â
|
|
int |
requestID |
Request that generated event |
|
string |
signature |
Type signature |
|
Case FieldAccess - if eventKind is
JDWP.EventKind.FIELD_ACCESS: |
Notification of a field access in the target VM. Field
modifications are not considered field accesses. Requires
canWatchFieldAccess capability - see CapabilitiesNew. |
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Accessing thread |
|
location |
location |
Location of access |
|
byte |
refTypeTag |
Kind of reference type. See JDWP.TypeTag |
|
referenceTypeID |
typeID |
Type of field |
|
fieldID |
fieldID |
Field being accessed |
|
tagged-objectID |
object |
Object being accessed (null=0 for statics |
|
Case FieldModification - if eventKind is
JDWP.EventKind.FIELD_MODIFICATION: |
Notification of a field modification in the target VM. Requires
canWatchFieldModification capability - see CapabilitiesNew. |
|
int |
requestID |
Request that generated event |
|
threadID |
thread |
Modifying thread |
|
location |
location |
Location of modify |
|
byte |
refTypeTag |
Kind of reference type. See JDWP.TypeTag |
|
referenceTypeID |
typeID |
Type of field |
|
fieldID |
fieldID |
Field being modified |
|
tagged-objectID |
object |
Object being modified (null=0 for statics |
|
value |
valueToBe |
Value to be assigned |
|
Case VMDeath - if eventKind is
JDWP.EventKind.VM_DEATH: |
 |
|
int |
requestID |
Request that generated event |
|
|
|
NONE |
0 |
No error has occurred. Â |
INVALID_THREAD |
10 |
Passed thread is null, is not a valid thread or has exited.
 |
INVALID_THREAD_GROUP |
11 |
Thread group invalid. Â |
INVALID_PRIORITY |
12 |
Invalid priority. Â |
THREAD_NOT_SUSPENDED |
13 |
If the specified thread has not been suspended by an event.
 |
THREAD_SUSPENDED |
14 |
Thread already suspended. Â |
THREAD_NOT_ALIVE |
15 |
Thread has not been started or is now dead. Â |
INVALID_OBJECT |
20 |
If this reference type has been unloaded and garbage collected.
 |
INVALID_CLASS |
21 |
Invalid class. Â |
CLASS_NOT_PREPARED |
22 |
Class has been loaded but not yet prepared. Â |
INVALID_METHODID |
23 |
Invalid method. Â |
INVALID_LOCATION |
24 |
Invalid location. Â |
INVALID_FIELDID |
25 |
Invalid field. Â |
INVALID_FRAMEID |
30 |
Invalid jframeID. Â |
NO_MORE_FRAMES |
31 |
There are no more Java or JNI frames on the call stack.
 |
OPAQUE_FRAME |
32 |
Information about the frame is not available. Â
|
NOT_CURRENT_FRAME |
33 |
Operation can only be performed on current frame. Â
|
TYPE_MISMATCH |
34 |
The variable is not an appropriate type for the function used.
 |
INVALID_SLOT |
35 |
Invalid slot. Â |
DUPLICATE |
40 |
Item already set. Â |
NOT_FOUND |
41 |
Desired element not found. Â |
INVALID_MODULE |
42 |
Invalid module. Â
|
INVALID_MONITOR |
50 |
Invalid monitor. Â |
NOT_MONITOR_OWNER |
51 |
This thread doesn't own the monitor. Â |
INTERRUPT |
52 |
The call has been interrupted before completion. Â
|
INVALID_CLASS_FORMAT |
60 |
The virtual machine attempted to read a class file and
determined that the file is malformed or otherwise cannot be
interpreted as a class file. Â |
CIRCULAR_CLASS_DEFINITION |
61 |
A circularity has been detected while initializing a class.
 |
FAILS_VERIFICATION |
62 |
The verifier detected that a class file, though well formed,
contained some sort of internal inconsistency or security problem.
 |
ADD_METHOD_NOT_IMPLEMENTED |
63 |
Adding methods has not been implemented. Â |
SCHEMA_CHANGE_NOT_IMPLEMENTED |
64 |
Schema change has not been implemented. Â |
INVALID_TYPESTATE |
65 |
The state of the thread has been modified, and is now
inconsistent. Â |
HIERARCHY_CHANGE_NOT_IMPLEMENTED |
66 |
A direct superclass is different for the new class version, or
the set of directly implemented interfaces is different and
canUnrestrictedlyRedefineClasses is false. Â |
DELETE_METHOD_NOT_IMPLEMENTED |
67 |
The new class version does not declare a method declared in the
old class version and canUnrestrictedlyRedefineClasses is false.
 |
UNSUPPORTED_VERSION |
68 |
A class file has a version number not supported by this VM.
 |
NAMES_DONT_MATCH |
69 |
The class name defined in the new class file is different from
the name in the old class object. Â |
CLASS_MODIFIERS_CHANGE_NOT_IMPLEMENTED |
70 |
The new class version has different modifiers and and
canUnrestrictedlyRedefineClasses is false. Â |
METHOD_MODIFIERS_CHANGE_NOT_IMPLEMENTED |
71 |
A method in the new class version has different modifiers than
its counterpart in the old class version and and
canUnrestrictedlyRedefineClasses is false. Â |
NOT_IMPLEMENTED |
99 |
The functionality is not implemented in this virtual machine.
 |
NULL_POINTER |
100 |
Invalid pointer. Â |
ABSENT_INFORMATION |
101 |
Desired information is not available. Â |
INVALID_EVENT_TYPE |
102 |
The specified event type id is not recognized. Â
|
ILLEGAL_ARGUMENT |
103 |
Illegal argument. Â |
OUT_OF_MEMORY |
110 |
The function needed to allocate memory and no more memory was
available for allocation. Â |
ACCESS_DENIED |
111 |
Debugging has not been enabled in this virtual machine. JVMTI
cannot be used. Â |
VM_DEAD |
112 |
The virtual machine is not running. Â |
INTERNAL |
113 |
An unexpected internal error has occurred. Â |
UNATTACHED_THREAD |
115 |
The thread being used to call this function is not attached to
the virtual machine. Calls must be made from attached threads.
 |
INVALID_TAG |
500 |
object type id or class tag. Â |
ALREADY_INVOKING |
502 |
Previous invoke not complete. Â |
INVALID_INDEX |
503 |
Index is invalid. Â |
INVALID_LENGTH |
504 |
The length is invalid. Â |
INVALID_STRING |
506 |
The string is invalid. Â |
INVALID_CLASS_LOADER |
507 |
The class loader is invalid. Â |
INVALID_ARRAY |
508 |
The array is invalid. Â |
TRANSPORT_LOAD |
509 |
Unable to load the transport. Â |
TRANSPORT_INIT |
510 |
Unable to initialize the transport. Â |
NATIVE_METHOD |
511 |
 |
INVALID_COUNT |
512 |
The count is invalid. Â |
|
|
|
SINGLE_STEP |
1 |
 |
BREAKPOINT |
2 |
 |
FRAME_POP |
3 |
 |
EXCEPTION |
4 |
 |
USER_DEFINED |
5 |
 |
THREAD_START |
6 |
 |
THREAD_DEATH |
7 |
 |
THREAD_END |
7 |
obsolete - was used in jvmdi  |
CLASS_PREPARE |
8 |
 |
CLASS_UNLOAD |
9 |
 |
CLASS_LOAD |
10 |
 |
FIELD_ACCESS |
20 |
 |
FIELD_MODIFICATION |
21 |
 |
EXCEPTION_CATCH |
30 |
 |
METHOD_ENTRY |
40 |
 |
METHOD_EXIT |
41 |
 |
METHOD_EXIT_WITH_RETURN_VALUE |
42 |
 |
MONITOR_CONTENDED_ENTER |
43 |
 |
MONITOR_CONTENDED_ENTERED |
44 |
 |
MONITOR_WAIT |
45 |
 |
MONITOR_WAITED |
46 |
 |
VM_START |
90 |
 |
VM_INIT |
90 |
obsolete - was used in jvmdi  |
VM_DEATH |
99 |
 |
VM_DISCONNECTED |
100 |
Never sent across JDWP Â |
|
|
|
ZOMBIE |
0 |
 |
RUNNING |
1 |
 |
SLEEPING |
2 |
 |
MONITOR |
3 |
 |
WAIT |
4 |
 |
|
|
|
SUSPEND_STATUS_SUSPENDED |
0x1 |
 |
|
|
|
VERIFIED |
1 |
 |
PREPARED |
2 |
 |
INITIALIZED |
4 |
 |
ERROR |
8 |
 |
|
|
|
CLASS |
1 |
ReferenceType is a class. Â |
INTERFACE |
2 |
ReferenceType is an interface. Â |
ARRAY |
3 |
ReferenceType is an array. Â |
|
|
|
ARRAY |
91 |
'[' - an array object (objectID size). Â |
BYTE |
66 |
'B' - a byte value (1 byte). Â |
CHAR |
67 |
'C' - a character value (2 bytes). Â |
OBJECT |
76 |
'L' - an object (objectID size). Â |
FLOAT |
70 |
'F' - a float value (4 bytes). Â |
DOUBLE |
68 |
'D' - a double value (8 bytes). Â |
INT |
73 |
'I' - an int value (4 bytes). Â |
LONG |
74 |
'J' - a long value (8 bytes). Â |
SHORT |
83 |
'S' - a short value (2 bytes). Â |
VOID |
86 |
'V' - a void value (no bytes). Â |
BOOLEAN |
90 |
'Z' - a boolean value (1 byte). Â |
STRING |
115 |
's' - a String object (objectID size). Â |
THREAD |
116 |
't' - a Thread object (objectID size). Â |
THREAD_GROUP |
103 |
'g' - a ThreadGroup object (objectID size). Â |
CLASS_LOADER |
108 |
'l' - a ClassLoader object (objectID size). Â |
CLASS_OBJECT |
99 |
'c' - a class object object (objectID size). Â |
|
|
|
INTO |
0 |
Step into any method calls that occur before the end of the
step. Â |
OVER |
1 |
Step over any method calls that occur before the end of the
step. Â |
OUT |
2 |
Step out of the current method. Â |
|
|
|
MIN |
0 |
Step by the minimum possible amount (often a bytecode
instruction). Â |
LINE |
1 |
Step to the next source line unless there is no line number
information in which case a MIN step is done instead.
 |
|
|
|
NONE |
0 |
Suspend no threads when this event is encountered. Â
|
EVENT_THREAD |
1 |
Suspend the event thread when this event is encountered.
 |
ALL |
2 |
Suspend all threads when this event is encountered.
 |
The invoke options are a combination of zero or more of the
following bit flags:
|
|
|
INVOKE_SINGLE_THREADED |
0x01 |
otherwise, all threads started. Â |
INVOKE_NONVIRTUAL |
0x02 |
otherwise, normal virtual invoke (instance methods only)
 |