Throwable class is the superclass of all errors and
+ * The {@code Throwable} class is the superclass of all errors and
* exceptions in the Java language. Only objects that are instances of this
* class (or one of its subclasses) are thrown by the Java Virtual Machine or
- * can be thrown by the Java throw statement. Similarly, only
+ * can be thrown by the Java {@code throw} statement. Similarly, only
* this class or one of its subclasses can be the argument type in a
- * catch clause.
+ * {@code catch} clause.
*
* For the purposes of compile-time checking of exceptions, {@code
* Throwable} and any subclass of {@code Throwable} that is not also a
@@ -73,11 +73,11 @@
* permit the method to throw the cause directly. For example, suppose
* a persistent collection conforms to the {@link java.util.Collection
* Collection} interface, and that its persistence is implemented atop
- * java.io. Suppose the internals of the add method
+ * {@code java.io}. Suppose the internals of the {@code add} method
* can throw an {@link java.io.IOException IOException}. The implementation
- * can communicate the details of the IOException to its caller
- * while conforming to the Collection interface by wrapping the
- * IOException in an appropriate unchecked exception. (The
+ * can communicate the details of the {@code IOException} to its caller
+ * while conforming to the {@code Collection} interface by wrapping the
+ * {@code IOException} in an appropriate unchecked exception. (The
* specification for the persistent collection should indicate that it is
* capable of throwing such exceptions.)
*
@@ -86,7 +86,7 @@
* {@link #initCause(Throwable)} method. New throwable classes that
* wish to allow causes to be associated with them should provide constructors
* that take a cause and delegate (perhaps indirectly) to one of the
- * Throwable constructors that takes a cause. For example:
+ * {@code Throwable} constructors that takes a cause. For example:
*
* try {
* lowLevelOp();
@@ -94,10 +94,10 @@
* throw new HighLevelException(le); // Chaining-aware constructor
* }
*
- * Because the initCause method is public, it allows a cause to be
+ * Because the {@code initCause} method is public, it allows a cause to be
* associated with any throwable, even a "legacy throwable" whose
* implementation predates the addition of the exception chaining mechanism to
- * Throwable. For example:
+ * {@code Throwable}. For example:
*
* try {
* lowLevelOp();
@@ -121,28 +121,28 @@
* use the standard exception chaining mechanism, while continuing to
* implement their "legacy" chaining mechanisms for compatibility.
*
- * Further, as of release 1.4, many general purpose Throwable
+ *
Further, as of release 1.4, many general purpose {@code Throwable}
* classes (for example {@link Exception}, {@link RuntimeException},
* {@link Error}) have been retrofitted with constructors that take
* a cause. This was not strictly necessary, due to the existence of the
- * initCause method, but it is more convenient and expressive to
+ * {@code initCause} method, but it is more convenient and expressive to
* delegate to a constructor that takes a cause.
*
- *
By convention, class Throwable and its subclasses have two
+ *
By convention, class {@code Throwable} and its subclasses have two
* constructors, one that takes no arguments and one that takes a
- * String argument that can be used to produce a detail message.
+ * {@code String} argument that can be used to produce a detail message.
* Further, those subclasses that might likely have a cause associated with
* them should have two more constructors, one that takes a
- * Throwable (the cause), and one that takes a
- * String (the detail message) and a Throwable (the
+ * {@code Throwable} (the cause), and one that takes a
+ * {@code String} (the detail message) and a {@code Throwable} (the
* cause).
*
*
Also introduced in release 1.4 is the {@link #getStackTrace()} method,
* which allows programmatic access to the stack trace information that was
* previously available only in text form, via the various forms of the
* {@link #printStackTrace()} method. This information has been added to the
- * serialized representation of this class so getStackTrace
- * and printStackTrace will operate properly on a throwable that
+ * serialized representation of this class so {@code getStackTrace}
+ * and {@code printStackTrace} will operate properly on a throwable that
* was obtained by deserialization.
*
* @author unascribed
@@ -162,7 +162,7 @@
/**
* Specific details about the Throwable. For example, for
- * FileNotFoundException, this contains the name of
+ * {@code FileNotFoundException}, this contains the name of
* the file that could not be found.
*
* @serial
@@ -212,7 +212,7 @@
private static final String SUPPRESSED_CAPTION = "Suppressed: ";
/**
- * Constructs a new throwable with null as its detail message.
+ * Constructs a new throwable with {@code null} as its detail message.
* The cause is not initialized, and may subsequently be initialized by a
* call to {@link #initCause}.
*
@@ -242,7 +242,7 @@
/**
* Constructs a new throwable with the specified detail message and
* cause.
Note that the detail message associated with
- * cause is not automatically incorporated in
+ * {@code cause} is not automatically incorporated in
* this throwable's detail message.
*
*
The {@link #fillInStackTrace()} method is called to initialize
@@ -251,7 +251,7 @@
* @param message the detail message (which is saved for later retrieval
* by the {@link #getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
- * {@link #getCause()} method). (A null value is
+ * {@link #getCause()} method). (A {@code null} value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.4
@@ -264,8 +264,8 @@
/**
* Constructs a new throwable with the specified cause and a detail
- * message of (cause==null ? null : cause.toString()) (which
- * typically contains the class and detail message of cause).
+ * message of {@code (cause==null ? null : cause.toString())} (which
+ * typically contains the class and detail message of {@code cause}).
* This constructor is useful for throwables that are little more than
* wrappers for other throwables (for example, {@link
* java.security.PrivilegedActionException}).
@@ -274,7 +274,7 @@
* the stack trace data in the newly created throwable.
*
* @param cause the cause (which is saved for later retrieval by the
- * {@link #getCause()} method). (A null value is
+ * {@link #getCause()} method). (A {@code null} value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.4
@@ -288,8 +288,8 @@
/**
* Returns the detail message string of this throwable.
*
- * @return the detail message string of this Throwable instance
- * (which may be null).
+ * @return the detail message string of this {@code Throwable} instance
+ * (which may be {@code null}).
*/
public String getMessage() {
return detailMessage;
@@ -300,7 +300,7 @@
* Subclasses may override this method in order to produce a
* locale-specific message. For subclasses that do not override this
* method, the default implementation returns the same result as
- * getMessage().
+ * {@code getMessage()}.
*
* @return The localized description of this throwable.
* @since JDK1.1
@@ -310,22 +310,22 @@
}
/**
- * Returns the cause of this throwable or null if the
+ * Returns the cause of this throwable or {@code null} if the
* cause is nonexistent or unknown. (The cause is the throwable that
* caused this throwable to get thrown.)
*
*
This implementation returns the cause that was supplied via one of
- * the constructors requiring a Throwable, or that was set after
+ * the constructors requiring a {@code Throwable}, or that was set after
* creation with the {@link #initCause(Throwable)} method. While it is
* typically unnecessary to override this method, a subclass can override
* it to return a cause set by some other means. This is appropriate for
* a "legacy chained throwable" that predates the addition of chained
- * exceptions to Throwable. Note that it is not
- * necessary to override any of the PrintStackTrace methods,
- * all of which invoke the getCause method to determine the
+ * exceptions to {@code Throwable}. Note that it is not
+ * necessary to override any of the {@code PrintStackTrace} methods,
+ * all of which invoke the {@code getCause} method to determine the
* cause of a throwable.
*
- * @return the cause of this throwable or null if the
+ * @return the cause of this throwable or {@code null} if the
* cause is nonexistent or unknown.
* @since 1.4
*/
@@ -345,11 +345,11 @@
* even once.
*
* @param cause the cause (which is saved for later retrieval by the
- * {@link #getCause()} method). (A null value is
+ * {@link #getCause()} method). (A {@code null} value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
- * @return a reference to this Throwable instance.
- * @throws IllegalArgumentException if cause is this
+ * @return a reference to this {@code Throwable} instance.
+ * @throws IllegalArgumentException if {@code cause} is this
* throwable. (A throwable cannot be its own cause.)
* @throws IllegalStateException if this throwable was
* created with {@link #Throwable(Throwable)} or
@@ -375,7 +375,7 @@
*
Throwable object on the error output stream that is
- * the value of the field System.err. The first line of
+ * {@code Throwable} object on the error output stream that is
+ * the value of the field {@code System.err}. The first line of
* output contains the result of the {@link #toString()} method for
* this object. Remaining lines represent data previously recorded by
* the method {@link #fillInStackTrace()}. The format of this
@@ -435,7 +435,7 @@
* at Junk.c(Junk.java:21)
* ... 3 more
*
- * Note the presence of lines containing the characters "...".
+ * Note the presence of lines containing the characters {@code "..."}.
* These lines indicate that the remainder of the stack trace for this
* exception matches the indicated number of frames from the bottom of the
* stack trace of the exception that was caused by this exception (the
@@ -542,14 +542,17 @@
/**
* Prints this throwable and its backtrace to the specified print stream.
*
- * @param s PrintStream to use for output
+ * @param s {@code PrintStream} to use for output
*/
public void printStackTrace(PrintStream s) {
printStackTrace(new WrappedPrintStream(s));
}
private void printStackTrace(PrintStreamOrWriter s) {
- SetPrintWriter to use for output
+ * @param s {@code PrintWriter} to use for output
* @since JDK1.1
*/
public void printStackTrace(PrintWriter s) {
@@ -669,10 +672,10 @@
/**
* Fills in the execution stack trace. This method records within this
- * Throwable object information about the current state of
+ * {@code Throwable} object information about the current state of
* the stack frames for the current thread.
*
- * @return a reference to this Throwable instance.
+ * @return a reference to this {@code Throwable} instance.
* @see java.lang.Throwable#printStackTrace()
*/
public synchronized native Throwable fillInStackTrace();
@@ -694,7 +697,7 @@
* this throwable is permitted to return a zero-length array from this
* method. Generally speaking, the array returned by this method will
* contain one element for every frame that would be printed by
- * printStackTrace.
+ * {@code printStackTrace}.
*
* @return an array of stack trace elements representing the stack trace
* pertaining to this throwable.
@@ -727,14 +730,14 @@
* read from a serialization stream.
*
* @param stackTrace the stack trace elements to be associated with
- * this Throwable. The specified array is copied by this
+ * this {@code Throwable}. The specified array is copied by this
* call; changes in the specified array after the method invocation
- * returns will have no affect on this Throwable's stack
+ * returns will have no affect on this {@code Throwable}'s stack
* trace.
*
- * @throws NullPointerException if stackTrace is
- * null, or if any of the elements of
- * stackTrace are null
+ * @throws NullPointerException if {@code stackTrace} is
+ * {@code null}, or if any of the elements of
+ * {@code stackTrace} are {@code null}
*
* @since 1.4
*/
@@ -761,8 +764,8 @@
* package-protection for use by SharedSecrets.
*
* @param index index of the element to return.
- * @throws IndexOutOfBoundsException if index < 0 ||
- * index >= getStackTraceDepth()
+ * @throws IndexOutOfBoundsException if {@code index < 0 ||
+ * index >= getStackTraceDepth() }
*/
native StackTraceElement getStackTraceElement(int index);
@@ -794,14 +797,28 @@
* were suppressed, typically by the automatic resource management
* statement, in order to deliver this exception.
*
+ * Note that when one exception {@linkplain
+ * #initCause(Throwable) causes} another exception, the first
+ * exception is usually caught and then the second exception is
+ * thrown in response. In contrast, when when one exception
+ * suppresses another, two exceptions are thrown in sibling code
+ * blocks, such as in a {@code try} block and in its {@code
+ * finally} block, and control flow can only continue with one
+ * exception so the second is recorded as a suppressed exception
+ * of the first.
+ *
* @param exception the exception to be added to the list of
* suppressed exceptions
* @throws NullPointerException if {@code exception} is null
+ * @throws IllegalArgumentException if {@code exception} is this
+ * throwable; a throwable cannot suppress itself.
* @since 1.7
*/
public synchronized void addSuppressedException(Throwable exception) {
if (exception == null)
throw new NullPointerException(NULL_CAUSE_MESSAGE);
+ if (exception == this)
+ throw new IllegalArgumentException("Self-suppression not permitted");
if (suppressedExceptions.size() == 0)
suppressedExceptions = new ArrayList