{@code Class} has no public constructor. Instead {@code Class} * objects are constructed automatically by the Java Virtual Machine as classes * are loaded and by calls to the {@code defineClass} method in the class * loader. * *
The following example uses a {@code Class} object to print the * class name of an object: * *
* void printClassName(Object obj) {
* System.out.println("The class of " + obj +
* " is " + obj.getClass().getName());
* }
* It is also possible to get the {@code Class} object for a named * type (or for void) using a class literal. See Section 15.8.2 of * The Java™ Language Specification. * For example: * *
* {@code System.out.println("The name of class Foo is: "+Foo.class.getName());} ** * @param
@{@code interface}, as appropriate), followed
* by the type's name, followed by an angle-bracketed
* comma-separated list of the type's type parameters, if any.
*
* A space is used to separate modifiers from one another and to
* separate any modifiers from the kind of type. The modifiers
* occur in canonical order. If there are no type parameters, the
* type parameter list is elided.
*
* Note that since information about the runtime representation * of a type is being generated, modifiers not present on the * originating source code or illegal on the originating source * code may be present. * * @return a string describing this {@code Class}, including * information about modifiers and type parameters * * @since 1.8 */ public String toGenericString() { if (isPrimitive()) { return toString(); } else { StringBuilder sb = new StringBuilder(); // Class modifiers are a superset of interface modifiers int modifiers = getModifiers() & Modifier.classModifiers(); if (modifiers != 0) { sb.append(Modifier.toString(modifiers)); sb.append(' '); } if (isAnnotation()) { sb.append('@'); } if (isInterface()) { // Note: all annotation types are interfaces sb.append("interface"); } else { if (isEnum()) sb.append("enum"); else sb.append("class"); } sb.append(' '); sb.append(getName()); TypeVariable[] typeparms = getTypeParameters(); if (typeparms.length > 0) { boolean first = true; sb.append('<'); for(TypeVariable typeparm: typeparms) { if (!first) sb.append(','); sb.append(typeparm.getTypeName()); first = false; } sb.append('>'); } return sb.toString(); } } /** * Returns the {@code Class} object associated with the class or * interface with the given string name. Invoking this method is * equivalent to: * *
* {@code Class.forName(className, true, currentLoader)} ** * where {@code currentLoader} denotes the defining class loader of * the current class. * *
For example, the following code fragment returns the * runtime {@code Class} descriptor for the class named * {@code java.lang.Thread}: * *
* {@code Class t = Class.forName("java.lang.Thread")} **
* A call to {@code forName("X")} causes the class named * {@code X} to be initialized. * * @param className the fully qualified name of the desired class. * @return the {@code Class} object for the class with the * specified name. * @exception LinkageError if the linkage fails * @exception ExceptionInInitializerError if the initialization provoked * by this method fails * @exception ClassNotFoundException if the class cannot be located */ @CallerSensitive public static Class forName(String className) throws ClassNotFoundException { Class caller = Reflection.getCallerClass(); return forName0(className, true, ClassLoader.getClassLoader(caller), caller); } /** * Returns the {@code Class} object associated with the class or * interface with the given string name, using the given class loader. * Given the fully qualified name for a class or interface (in the same * format returned by {@code getName}) this method attempts to * locate, load, and link the class or interface. The specified class * loader is used to load the class or interface. If the parameter * {@code loader} is null, the class is loaded through the bootstrap * class loader. The class is initialized only if the * {@code initialize} parameter is {@code true} and if it has * not been initialized earlier. * *
If {@code name} denotes a primitive type or void, an attempt * will be made to locate a user-defined class in the unnamed package whose * name is {@code name}. Therefore, this method cannot be used to * obtain any of the {@code Class} objects representing primitive * types or void. * *
If {@code name} denotes an array class, the component type of * the array class is loaded but not initialized. * *
For example, in an instance method the expression: * *
* {@code Class.forName("Foo")} ** * is equivalent to: * *
* {@code Class.forName("Foo", true, this.getClass().getClassLoader())} ** * Note that this method throws errors related to loading, linking or * initializing as specified in Sections 12.2, 12.3 and 12.4 of The * Java Language Specification. * Note that this method does not check whether the requested class * is accessible to its caller. * *
If the {@code loader} is {@code null}, and a security * manager is present, and the caller's class loader is not null, then this * method calls the security manager's {@code checkPermission} method * with a {@code RuntimePermission("getClassLoader")} permission to * ensure it's ok to access the bootstrap class loader. * * @param name fully qualified name of the desired class * @param initialize if {@code true} the class will be initialized. * See Section 12.4 of The Java Language Specification. * @param loader class loader from which the class must be loaded * @return class object representing the desired class * * @exception LinkageError if the linkage fails * @exception ExceptionInInitializerError if the initialization provoked * by this method fails * @exception ClassNotFoundException if the class cannot be located by * the specified class loader * * @see java.lang.Class#forName(String) * @see java.lang.ClassLoader * @since 1.2 */ @CallerSensitive public static Class forName(String name, boolean initialize, ClassLoader loader) throws ClassNotFoundException { Class caller = null; SecurityManager sm = System.getSecurityManager(); if (sm != null) { // Reflective call to get caller class is only needed if a security manager // is present. Avoid the overhead of making this call otherwise. caller = Reflection.getCallerClass(); if (sun.misc.VM.isSystemDomainLoader(loader)) { ClassLoader ccl = ClassLoader.getClassLoader(caller); if (!sun.misc.VM.isSystemDomainLoader(ccl)) { sm.checkPermission( SecurityConstants.GET_CLASSLOADER_PERMISSION); } } } return forName0(name, initialize, loader, caller); } /** Called after security check for system loader access checks have been made. */ private static native Class forName0(String name, boolean initialize, ClassLoader loader, Class caller) throws ClassNotFoundException; /** * Creates a new instance of the class represented by this {@code Class} * object. The class is instantiated as if by a {@code new} * expression with an empty argument list. The class is initialized if it * has not already been initialized. * *
Note that this method propagates any exception thrown by the
* nullary constructor, including a checked exception. Use of
* this method effectively bypasses the compile-time exception
* checking that would otherwise be performed by the compiler.
* The {@link
* java.lang.reflect.Constructor#newInstance(java.lang.Object...)
* Constructor.newInstance} method avoids this problem by wrapping
* any exception thrown by the constructor in a (checked) {@link
* java.lang.reflect.InvocationTargetException}.
*
* @return a newly allocated instance of the class represented by this
* object.
* @throws IllegalAccessException if the class or its nullary
* constructor is not accessible.
* @throws InstantiationException
* if this {@code Class} represents an abstract class,
* an interface, an array class, a primitive type, or void;
* or if the class has no nullary constructor;
* or if the instantiation fails for some other reason.
* @throws ExceptionInInitializerError if the initialization
* provoked by this method fails.
* @throws SecurityException
* If a security manager, s, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*/
@CallerSensitive
public T newInstance()
throws InstantiationException, IllegalAccessException
{
if (System.getSecurityManager() != null) {
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false);
}
// NOTE: the following code may not be strictly correct under
// the current Java memory model.
// Constructor lookup
if (cachedConstructor == null) {
if (this == Class.class) {
throw new IllegalAccessException(
"Can not call newInstance() on the Class for java.lang.Class"
);
}
try {
Class[] empty = {};
final Constructor Specifically, if this {@code Class} object represents a
* declared class, this method returns {@code true} if the specified
* {@code Object} argument is an instance of the represented class (or
* of any of its subclasses); it returns {@code false} otherwise. If
* this {@code Class} object represents an array class, this method
* returns {@code true} if the specified {@code Object} argument
* can be converted to an object of the array class by an identity
* conversion or by a widening reference conversion; it returns
* {@code false} otherwise. If this {@code Class} object
* represents an interface, this method returns {@code true} if the
* class or any superclass of the specified {@code Object} argument
* implements this interface; it returns {@code false} otherwise. If
* this {@code Class} object represents a primitive type, this method
* returns {@code false}.
*
* @param obj the object to check
* @return true if {@code obj} is an instance of this class
*
* @since 1.1
*/
public native boolean isInstance(Object obj);
/**
* Determines if the class or interface represented by this
* {@code Class} object is either the same as, or is a superclass or
* superinterface of, the class or interface represented by the specified
* {@code Class} parameter. It returns {@code true} if so;
* otherwise it returns {@code false}. If this {@code Class}
* object represents a primitive type, this method returns
* {@code true} if the specified {@code Class} parameter is
* exactly this {@code Class} object; otherwise it returns
* {@code false}.
*
* Specifically, this method tests whether the type represented by the
* specified {@code Class} parameter can be converted to the type
* represented by this {@code Class} object via an identity conversion
* or via a widening reference conversion. See The Java Language
* Specification, sections 5.1.1 and 5.1.4 , for details.
*
* @param cls the {@code Class} object to be checked
* @return the {@code boolean} value indicating whether objects of the
* type {@code cls} can be assigned to objects of this class
* @exception NullPointerException if the specified Class parameter is
* null.
* @since 1.1
*/
public native boolean isAssignableFrom(Class cls);
/**
* Determines if the specified {@code Class} object represents an
* interface type.
*
* @return {@code true} if this object represents an interface;
* {@code false} otherwise.
*/
public native boolean isInterface();
/**
* Determines if this {@code Class} object represents an array class.
*
* @return {@code true} if this object represents an array class;
* {@code false} otherwise.
* @since 1.1
*/
public native boolean isArray();
/**
* Determines if the specified {@code Class} object represents a
* primitive type.
*
* There are nine predefined {@code Class} objects to represent
* the eight primitive types and void. These are created by the Java
* Virtual Machine, and have the same names as the primitive types that
* they represent, namely {@code boolean}, {@code byte},
* {@code char}, {@code short}, {@code int},
* {@code long}, {@code float}, and {@code double}.
*
* These objects may only be accessed via the following public static
* final variables, and are the only {@code Class} objects for which
* this method returns {@code true}.
*
* @return true if and only if this class represents a primitive type
*
* @see java.lang.Boolean#TYPE
* @see java.lang.Character#TYPE
* @see java.lang.Byte#TYPE
* @see java.lang.Short#TYPE
* @see java.lang.Integer#TYPE
* @see java.lang.Long#TYPE
* @see java.lang.Float#TYPE
* @see java.lang.Double#TYPE
* @see java.lang.Void#TYPE
* @since 1.1
*/
public native boolean isPrimitive();
/**
* Returns true if this {@code Class} object represents an annotation
* type. Note that if this method returns true, {@link #isInterface()}
* would also return true, as all annotation types are also interfaces.
*
* @return {@code true} if this class object represents an annotation
* type; {@code false} otherwise
* @since 1.5
*/
public boolean isAnnotation() {
return (getModifiers() & ANNOTATION) != 0;
}
/**
* Returns {@code true} if this class is a synthetic class;
* returns {@code false} otherwise.
* @return {@code true} if and only if this class is a synthetic class as
* defined by the Java Language Specification.
* @jls 13.1 The Form of a Binary
* @since 1.5
*/
public boolean isSynthetic() {
return (getModifiers() & SYNTHETIC) != 0;
}
/**
* Returns the name of the entity (class, interface, array class,
* primitive type, or void) represented by this {@code Class} object,
* as a {@code String}.
*
* If this class object represents a reference type that is not an
* array type then the binary name of the class is returned, as specified
* by
* The Java™ Language Specification.
*
* If this class object represents a primitive type or void, then the
* name returned is a {@code String} equal to the Java language
* keyword corresponding to the primitive type or void.
*
* If this class object represents a class of arrays, then the internal
* form of the name consists of the name of the element type preceded by
* one or more '{@code [}' characters representing the depth of the array
* nesting. The encoding of element type names is as follows:
*
* The class or interface name classname is the binary name of
* the class specified above.
*
* Examples:
* If a security manager is present, and the caller's class loader is
* not null and the caller's class loader is not the same as or an ancestor of
* the class loader for the class whose class loader is requested, then
* this method calls the security manager's {@code checkPermission}
* method with a {@code RuntimePermission("getClassLoader")}
* permission to ensure it's ok to access the class loader for the class.
*
* If this object
* represents a primitive type or void, null is returned.
*
* @return the class loader that loaded the class or interface
* represented by this object.
* @throws SecurityException
* if a security manager exists and its
* {@code checkPermission} method denies
* access to the class loader for the class.
* @see java.lang.ClassLoader
* @see SecurityManager#checkPermission
* @see java.lang.RuntimePermission
*/
@CallerSensitive
public ClassLoader getClassLoader() {
ClassLoader cl = getClassLoader0();
if (cl == null)
return null;
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
}
return cl;
}
// Package-private to allow ClassLoader access
ClassLoader getClassLoader0() { return classLoader; }
// Initialized in JVM not by private constructor
// This field is an internal optimization for Class.getClassLoader() and
// should not be returned by Class.class.getDeclaredField()
private final ClassLoader classLoader;
/**
* Returns an array of {@code TypeVariable} objects that represent the
* type variables declared by the generic declaration represented by this
* {@code GenericDeclaration} object, in declaration order. Returns an
* array of length 0 if the underlying generic declaration declares no type
* variables.
*
* @return an array of {@code TypeVariable} objects that represent
* the type variables declared by this generic declaration
* @throws java.lang.reflect.GenericSignatureFormatError if the generic
* signature of this generic declaration does not conform to
* the format specified in
* The Java™ Virtual Machine Specification
* @since 1.5
*/
@SuppressWarnings("unchecked")
public TypeVariable If the superclass is a parameterized type, the {@code Type}
* object returned must accurately reflect the actual type
* parameters used in the source code. The parameterized type
* representing the superclass is created if it had not been
* created before. See the declaration of {@link
* java.lang.reflect.ParameterizedType ParameterizedType} for the
* semantics of the creation process for parameterized types. If
* this {@code Class} represents either the {@code Object}
* class, an interface, a primitive type, or void, then null is
* returned. If this object represents an array class then the
* {@code Class} object representing the {@code Object} class is
* returned.
*
* @throws java.lang.reflect.GenericSignatureFormatError if the generic
* class signature does not conform to the format specified in
* The Java™ Virtual Machine Specification
* @throws TypeNotPresentException if the generic superclass
* refers to a non-existent type declaration
* @throws java.lang.reflect.MalformedParameterizedTypeException if the
* generic superclass refers to a parameterized type that cannot be
* instantiated for any reason
* @return the direct superclass of the class represented by this object
* @since 1.5
*/
public Type getGenericSuperclass() {
ClassRepository info = getGenericInfo();
if (info == null) {
return getSuperclass();
}
// Historical irregularity:
// Generic signature marks interfaces with superclass = Object
// but this API returns null for interfaces
if (isInterface()) {
return null;
}
return info.getSuperclass();
}
/**
* Gets the package for this class. The class loader of this class is used
* to find the package. If the class was loaded by the bootstrap class
* loader the set of packages loaded from CLASSPATH is searched to find the
* package of the class. Null is returned if no package object was created
* by the class loader of this class.
*
* Packages have attributes for versions and specifications only if the
* information was defined in the manifests that accompany the classes, and
* if the class loader created the package instance with the attributes
* from the manifest.
*
* @return the package of the class, or null if no package
* information is available from the archive or codebase.
*/
public Package getPackage() {
return Package.getPackage(this);
}
/**
* Returns the interfaces directly implemented by the class or interface
* represented by this object.
*
* If this object represents a class, the return value is an array
* containing objects representing all interfaces directly implemented by
* the class. The order of the interface objects in the array corresponds
* to the order of the interface names in the {@code implements} clause of
* the declaration of the class represented by this object. For example,
* given the declaration:
* If this object represents an interface, the array contains objects
* representing all interfaces directly extended by the interface. The
* order of the interface objects in the array corresponds to the order of
* the interface names in the {@code extends} clause of the declaration of
* the interface represented by this object.
*
* If this object represents a class or interface that implements no
* interfaces, the method returns an array of length 0.
*
* If this object represents a primitive type or void, the method
* returns an array of length 0.
*
* If this {@code Class} object represents an array type, the
* interfaces {@code Cloneable} and {@code java.io.Serializable} are
* returned in that order.
*
* @return an array of interfaces directly implemented by this class
*/
public Class[] getInterfaces() {
ReflectionData If a superinterface is a parameterized type, the
* {@code Type} object returned for it must accurately reflect
* the actual type parameters used in the source code. The
* parameterized type representing each superinterface is created
* if it had not been created before. See the declaration of
* {@link java.lang.reflect.ParameterizedType ParameterizedType}
* for the semantics of the creation process for parameterized
* types.
*
* If this object represents a class, the return value is an array
* containing objects representing all interfaces directly implemented by
* the class. The order of the interface objects in the array corresponds
* to the order of the interface names in the {@code implements} clause of
* the declaration of the class represented by this object.
*
* If this object represents an interface, the array contains objects
* representing all interfaces directly extended by the interface. The
* order of the interface objects in the array corresponds to the order of
* the interface names in the {@code extends} clause of the declaration of
* the interface represented by this object.
*
* If this object represents a class or interface that implements no
* interfaces, the method returns an array of length 0.
*
* If this object represents a primitive type or void, the method
* returns an array of length 0.
*
* If this {@code Class} object represents an array type, the
* interfaces {@code Cloneable} and {@code java.io.Serializable} are
* returned in that order.
*
* @throws java.lang.reflect.GenericSignatureFormatError
* if the generic class signature does not conform to the format
* specified in
* The Java™ Virtual Machine Specification
* @throws TypeNotPresentException if any of the generic
* superinterfaces refers to a non-existent type declaration
* @throws java.lang.reflect.MalformedParameterizedTypeException
* if any of the generic superinterfaces refer to a parameterized
* type that cannot be instantiated for any reason
* @return an array of interfaces directly implemented by this class
* @since 1.5
*/
public Type[] getGenericInterfaces() {
ClassRepository info = getGenericInfo();
return (info == null) ? getInterfaces() : info.getSuperInterfaces();
}
/**
* Returns the {@code Class} representing the component type of an
* array. If this class does not represent an array class this method
* returns null.
*
* @return the {@code Class} representing the component type of this
* class if this class is an array
* @see java.lang.reflect.Array
* @since 1.1
*/
public Class getComponentType() {
// Only return for array types. Storage may be reused for Class for instance types.
if (isArray()) {
return componentType;
} else {
return null;
}
}
private final Class componentType;
/**
* Returns the Java language modifiers for this class or interface, encoded
* in an integer. The modifiers consist of the Java Virtual Machine's
* constants for {@code public}, {@code protected},
* {@code private}, {@code final}, {@code static},
* {@code abstract} and {@code interface}; they should be decoded
* using the methods of class {@code Modifier}.
*
* If the underlying class is an array class, then its
* {@code public}, {@code private} and {@code protected}
* modifiers are the same as those of its component type. If this
* {@code Class} represents a primitive type or void, its
* {@code public} modifier is always {@code true}, and its
* {@code protected} and {@code private} modifiers are always
* {@code false}. If this object represents an array class, a
* primitive type or void, then its {@code final} modifier is always
* {@code true} and its interface modifier is always
* {@code false}. The values of its other modifiers are not determined
* by this specification.
*
* The modifier encodings are defined in The Java Virtual Machine
* Specification, table 4.1.
*
* @return the {@code int} representing the modifiers for this class
* @see java.lang.reflect.Modifier
* @since 1.1
*/
public native int getModifiers();
/**
* Gets the signers of this class.
*
* @return the signers of this class, or null if there are no signers. In
* particular, this method returns null if this object represents
* a primitive type or void.
* @since 1.1
*/
public native Object[] getSigners();
/**
* Set the signers of this class.
*/
native void setSigners(Object[] signers);
/**
* If this {@code Class} object represents a local or anonymous
* class within a method, returns a {@link
* java.lang.reflect.Method Method} object representing the
* immediately enclosing method of the underlying class. Returns
* {@code null} otherwise.
*
* In particular, this method returns {@code null} if the underlying
* class is a local or anonymous class immediately enclosed by a type
* declaration, instance initializer or static initializer.
*
* @return the immediately enclosing method of the underlying class, if
* that class is a local or anonymous class; otherwise {@code null}.
*
* @throws SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
* The simple name of an array is the simple name of the
* component type with "[]" appended. In particular the simple
* name of an array whose component type is anonymous is "[]".
*
* @return the simple name of the underlying class
* @since 1.5
*/
public String getSimpleName() {
if (isArray())
return getComponentType().getSimpleName()+"[]";
String simpleName = getSimpleBinaryName();
if (simpleName == null) { // top level class
simpleName = getName();
return simpleName.substring(simpleName.lastIndexOf('.')+1); // strip the package name
}
// According to JLS3 "Binary Compatibility" (13.1) the binary
// name of non-package classes (not top level) is the binary
// name of the immediately enclosing class followed by a '$' followed by:
// (for nested and inner classes): the simple name.
// (for local classes): 1 or more digits followed by the simple name.
// (for anonymous classes): 1 or more digits.
// Since getSimpleBinaryName() will strip the binary name of
// the immediately enclosing class, we are now looking at a
// string that matches the regular expression "\$[0-9]*"
// followed by a simple name (considering the simple of an
// anonymous class to be the empty string).
// Remove leading "\$[0-9]*" from the name
int length = simpleName.length();
if (length < 1 || simpleName.charAt(0) != '$')
throw new InternalError("Malformed class name");
int index = 1;
while (index < length && isAsciiDigit(simpleName.charAt(index)))
index++;
// Eventually, this is the empty string iff this is an anonymous class
return simpleName.substring(index);
}
/**
* Return an informative string for the name of this type.
*
* @return an informative string for the name of this type
* @since 1.8
*/
public String getTypeName() {
if (isArray()) {
try {
Class cl = this;
int dimensions = 0;
while (cl.isArray()) {
dimensions++;
cl = cl.getComponentType();
}
StringBuilder sb = new StringBuilder();
sb.append(cl.getName());
for (int i = 0; i < dimensions; i++) {
sb.append("[]");
}
return sb.toString();
} catch (Throwable e) { /*FALLTHRU*/ }
}
return getName();
}
/**
* Character.isDigit answers {@code true} to some non-ascii
* digits. This one does not.
*/
private static boolean isAsciiDigit(char c) {
return '0' <= c && c <= '9';
}
/**
* Returns the canonical name of the underlying class as
* defined by the Java Language Specification. Returns null if
* the underlying class does not have a canonical name (i.e., if
* it is a local or anonymous class or an array whose component
* type does not have a canonical name).
* @return the canonical name of the underlying class if it exists, and
* {@code null} otherwise.
* @since 1.5
*/
public String getCanonicalName() {
if (isArray()) {
String canonicalName = getComponentType().getCanonicalName();
if (canonicalName != null)
return canonicalName + "[]";
else
return null;
}
if (isLocalOrAnonymousClass())
return null;
Class enclosingClass = getEnclosingClass();
if (enclosingClass == null) { // top level class
return getName();
} else {
String enclosingName = enclosingClass.getCanonicalName();
if (enclosingName == null)
return null;
return enclosingName + "." + getSimpleName();
}
}
/**
* Returns {@code true} if and only if the underlying class
* is an anonymous class.
*
* @return {@code true} if and only if this class is an anonymous class.
* @since 1.5
*/
public boolean isAnonymousClass() {
return "".equals(getSimpleName());
}
/**
* Returns {@code true} if and only if the underlying class
* is a local class.
*
* @return {@code true} if and only if this class is a local class.
* @since 1.5
*/
public boolean isLocalClass() {
return isLocalOrAnonymousClass() && !isAnonymousClass();
}
/**
* Returns {@code true} if and only if the underlying class
* is a member class.
*
* @return {@code true} if and only if this class is a member class.
* @since 1.5
*/
public boolean isMemberClass() {
return getSimpleBinaryName() != null && !isLocalOrAnonymousClass();
}
/**
* Returns the "simple binary name" of the underlying class, i.e.,
* the binary name without the leading enclosing class name.
* Returns {@code null} if the underlying class is a top level
* class.
*/
private String getSimpleBinaryName() {
Class enclosingClass = getEnclosingClass();
if (enclosingClass == null) // top level class
return null;
// Otherwise, strip the enclosing class' name
try {
return getName().substring(enclosingClass.getName().length());
} catch (IndexOutOfBoundsException ex) {
throw new InternalError("Malformed class name", ex);
}
}
/**
* Returns {@code true} if this is a local class or an anonymous
* class. Returns {@code false} otherwise.
*/
private boolean isLocalOrAnonymousClass() {
// JVM Spec 4.8.6: A class must have an EnclosingMethod
// attribute if and only if it is a local class or an
// anonymous class.
return getEnclosingMethodInfo() != null;
}
/**
* Returns an array containing {@code Class} objects representing all
* the public classes and interfaces that are members of the class
* represented by this {@code Class} object. This includes public
* class and interface members inherited from superclasses and public class
* and interface members declared by the class. This method returns an
* array of length 0 if this {@code Class} object has no public member
* classes or interfaces. This method also returns an array of length 0 if
* this {@code Class} object represents a primitive type, an array
* class, or void.
*
* @return the array of {@code Class} objects representing the public
* members of this class
* @throws SecurityException
* If a security manager, s, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*
* @since 1.1
*/
@CallerSensitive
public Class[] getClasses() {
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false);
// Privileged so this implementation can look at DECLARED classes,
// something the caller might not have privilege to do. The code here
// is allowed to look at DECLARED classes because (1) it does not hand
// out anything other than public members and (2) public member access
// has already been ok'd by the SecurityManager.
return java.security.AccessController.doPrivileged(
new java.security.PrivilegedAction If this {@code Class} object represents a class or interface with no
* no accessible public fields, then this method returns an array of length
* 0.
*
* If this {@code Class} object represents a class, then this method
* returns the public fields of the class and of all its superclasses and
* superinterfaces.
*
* If this {@code Class} object represents an interface, then this
* method returns the fields of the interface and of all its
* superinterfaces.
*
* If this {@code Class} object represents an array type, a primitive
* type, or void, then this method returns an array of length 0.
*
* The elements in the returned array are not sorted and are not in any
* particular order.
*
* @return the array of {@code Field} objects representing the
* public fields
* @throws SecurityException
* If a security manager, s, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*
* @since 1.1
* @jls 8.2 Class Members
* @jls 8.3 Field Declarations
*/
@CallerSensitive
public Field[] getFields() throws SecurityException {
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
return copyFields(privateGetPublicFields(null));
}
/**
* Returns an array containing {@code Method} objects reflecting all the
* public methods of the class or interface represented by this {@code
* Class} object, including those declared by the class or interface and
* those inherited from superclasses and superinterfaces.
*
* If this {@code Class} object represents a type that has multiple
* public methods with the same name and parameter types, but different
* return types, then the returned array has a {@code Method} object for
* each such method.
*
* If this {@code Class} object represents a type with a class
* initialization method {@code If this {@code Class} object represents an array type, then the
* returned array has a {@code Method} object for each of the public
* methods inherited by the array type from {@code Object}. It does not
* contain a {@code Method} object for {@code clone()}.
*
* If this {@code Class} object represents an interface then the
* returned array does not contain any implicitly declared methods from
* {@code Object}. Therefore, if no methods are explicitly declared in
* this interface or any of its superinterfaces then the returned array
* has length 0. (Note that a {@code Class} object which represents a class
* always has public methods, inherited from {@code Object}.)
*
* If this {@code Class} object represents a primitive type or void,
* then the returned array has length 0.
*
* Static methods declared in superinterfaces of the class or interface
* represented by this {@code Class} object are not considered members of
* the class or interface.
*
* The elements in the returned array are not sorted and are not in any
* particular order.
*
* @return the array of {@code Method} objects representing the
* public methods of this class
* @throws SecurityException
* If a security manager, s, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*
* @jls 8.2 Class Members
* @jls 8.4 Method Declarations
* @since 1.1
*/
@CallerSensitive
public Method[] getMethods() throws SecurityException {
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
return copyMethods(privateGetPublicMethods());
}
/**
* Returns an array containing {@code Constructor} objects reflecting
* all the public constructors of the class represented by this
* {@code Class} object. An array of length 0 is returned if the
* class has no public constructors, or if the class is an array class, or
* if the class reflects a primitive type or void.
*
* Note that while this method returns an array of {@code
* Constructor The field to be reflected is determined by the algorithm that
* follows. Let C be the class or interface represented by this object:
*
* If this {@code Class} object represents an array type, then this
* method does not find the {@code length} field of the array type.
*
* @param name the field name
* @return the {@code Field} object of this class specified by
* {@code name}
* @throws NoSuchFieldException if a field with the specified name is
* not found.
* @throws NullPointerException if {@code name} is {@code null}
* @throws SecurityException
* If a security manager, s, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*
* @since 1.1
* @jls 8.2 Class Members
* @jls 8.3 Field Declarations
*/
@CallerSensitive
public Field getField(String name)
throws NoSuchFieldException, SecurityException {
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
Field field = getField0(name);
if (field == null) {
throw new NoSuchFieldException(name);
}
return field;
}
/**
* Returns a {@code Method} object that reflects the specified public
* member method of the class or interface represented by this
* {@code Class} object. The {@code name} parameter is a
* {@code String} specifying the simple name of the desired method. The
* {@code parameterTypes} parameter is an array of {@code Class}
* objects that identify the method's formal parameter types, in declared
* order. If {@code parameterTypes} is {@code null}, it is
* treated as if it were an empty array.
*
* If the {@code name} is "{@code To find a matching method in a class or interface C: If C
* declares exactly one public method with the specified name and exactly
* the same formal parameter types, that is the method reflected. If more
* than one such method is found in C, and one of these methods has a
* return type that is more specific than any of the others, that method is
* reflected; otherwise one of the methods is chosen arbitrarily.
*
* Note that there may be more than one matching method in a
* class because while the Java language forbids a class to
* declare multiple methods with the same signature but different
* return types, the Java virtual machine does not. This
* increased flexibility in the virtual machine can be used to
* implement various language features. For example, covariant
* returns can be implemented with {@linkplain
* java.lang.reflect.Method#isBridge bridge methods}; the bridge
* method and the method being overridden would have the same
* signature but different return types.
*
* If this {@code Class} object represents an array type, then this
* method does not find the {@code clone()} method.
*
* Static methods declared in superinterfaces of the class or interface
* represented by this {@code Class} object are not considered members of
* the class or interface.
*
* @param name the name of the method
* @param parameterTypes the list of parameters
* @return the {@code Method} object that matches the specified
* {@code name} and {@code parameterTypes}
* @throws NoSuchMethodException if a matching method is not found
* or if the name is "<init>"or "<clinit>".
* @throws NullPointerException if {@code name} is {@code null}
* @throws SecurityException
* If a security manager, s, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*
* @jls 8.2 Class Members
* @jls 8.4 Method Declarations
* @since 1.1
*/
@CallerSensitive
public Method getMethod(String name, Class... parameterTypes)
throws NoSuchMethodException, SecurityException {
checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
Method method = getMethod0(name, parameterTypes, true);
if (method == null) {
throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
}
return method;
}
/**
* Returns a {@code Constructor} object that reflects the specified
* public constructor of the class represented by this {@code Class}
* object. The {@code parameterTypes} parameter is an array of
* {@code Class} objects that identify the constructor's formal
* parameter types, in declared order.
*
* If this {@code Class} object represents an inner class
* declared in a non-static context, the formal parameter types
* include the explicit enclosing instance as the first parameter.
*
* The constructor to reflect is the public constructor of the class
* represented by this {@code Class} object whose formal parameter
* types match those specified by {@code parameterTypes}.
*
* @param parameterTypes the parameter array
* @return the {@code Constructor} object of the public constructor that
* matches the specified {@code parameterTypes}
* @throws NoSuchMethodException if a matching method is not found.
* @throws SecurityException
* If a security manager, s, is present and
* the caller's class loader is not the same as or an
* ancestor of the class loader for the current class and
* invocation of {@link SecurityManager#checkPackageAccess
* s.checkPackageAccess()} denies access to the package
* of this class.
*
* @since 1.1
*/
@CallerSensitive
public Constructor If this {@code Class} object represents a class or interface with no
* declared fields, then this method returns an array of length 0.
*
* If this {@code Class} object represents an array type, a primitive
* type, or void, then this method returns an array of length 0.
*
* The elements in the returned array are not sorted and are not in any
* particular order.
*
* @return the array of {@code Field} objects representing all the
* declared fields of this class
* @throws SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
* If this {@code Class} object represents a type that has multiple
* declared methods with the same name and parameter types, but different
* return types, then the returned array has a {@code Method} object for
* each such method.
*
* If this {@code Class} object represents a type that has a class
* initialization method {@code If this {@code Class} object represents a class or interface with no
* declared methods, then the returned array has length 0.
*
* If this {@code Class} object represents an array type, a primitive
* type, or void, then the returned array has length 0.
*
* The elements in the returned array are not sorted and are not in any
* particular order.
*
* @return the array of {@code Method} objects representing all the
* declared methods of this class
* @throws SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
* See The Java Language Specification, section 8.2.
*
* @return the array of {@code Constructor} objects representing all the
* declared constructors of this class
* @throws SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
* If this {@code Class} object represents an array type, then this
* method does not find the {@code length} field of the array type.
*
* @param name the name of the field
* @return the {@code Field} object for the specified field in this
* class
* @throws NoSuchFieldException if a field with the specified name is
* not found.
* @throws NullPointerException if {@code name} is {@code null}
* @throws SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
* If this {@code Class} object represents an array type, then this
* method does not find the {@code clone()} method.
*
* @param name the name of the method
* @param parameterTypes the parameter array
* @return the {@code Method} object for the method of this class
* matching the specified name and parameters
* @throws NoSuchMethodException if a matching method is not found.
* @throws NullPointerException if {@code name} is {@code null}
* @throws SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
* Before delegation, an absolute resource name is constructed from the
* given resource name using this algorithm:
*
* Where the {@code modified_package_name} is the package name of this
* object with {@code '/'} substituted for {@code '.'}
* ('\u002e').
*
* Before delegation, an absolute resource name is constructed from the
* given resource name using this algorithm:
*
* Where the {@code modified_package_name} is the package name of this
* object with {@code '/'} substituted for {@code '.'}
* ('\u002e').
*
* Default policy: allow all clients access with normal Java access
* control.
*/
private void checkMemberAccess(int which, Class caller, boolean checkProxyInterfaces) {
final SecurityManager s = System.getSecurityManager();
if (s != null) {
/* Default policy allows access to all {@link Member#PUBLIC} members,
* as well as access to classes that have the same class loader as the caller.
* In all other cases, it requires RuntimePermission("accessDeclaredMembers")
* permission.
*/
final ClassLoader ccl = ClassLoader.getClassLoader(caller);
final ClassLoader cl = getClassLoader0();
if (which != Member.PUBLIC) {
if (ccl != cl) {
s.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
}
}
this.checkPackageAccess(ccl, checkProxyInterfaces);
}
}
/*
* Checks if a client loaded in ClassLoader ccl is allowed to access this
* class under the current package access policy. If access is denied,
* throw a SecurityException.
*/
private void checkPackageAccess(final ClassLoader ccl, boolean checkProxyInterfaces) {
final SecurityManager s = System.getSecurityManager();
if (s != null) {
final ClassLoader cl = getClassLoader0();
if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
String name = this.getName();
int i = name.lastIndexOf('.');
if (i != -1) {
// skip the package access check on a proxy class in default proxy package
String pkg = name.substring(0, i);
if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
s.checkPackageAccess(pkg);
}
}
}
// check package access on the proxy interfaces
if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
}
}
}
/**
* Add a package name prefix if the name is not absolute Remove leading "/"
* if name is absolute
*/
private String resolveName(String name) {
if (name == null) {
return name;
}
if (!name.startsWith("/")) {
Class c = this;
while (c.isArray()) {
c = c.getComponentType();
}
String baseName = c.getName();
int index = baseName.lastIndexOf('.');
if (index != -1) {
name = baseName.substring(0, index).replace('.', '/')
+"/"+name;
}
} else {
name = name.substring(1);
}
return name;
}
/**
* Atomic operations support.
*/
private static class Atomic {
// initialize Unsafe machinery here, since we need to call Class.class instance method
// and have to avoid calling it in the static initializer of the Class class...
private static final Unsafe unsafe = Unsafe.getUnsafe();
// offset of Class.reflectionData instance field
private static final long reflectionDataOffset;
// offset of Class.annotationType instance field
private static final long annotationTypeOffset;
// offset of Class.annotationData instance field
private static final long annotationDataOffset;
static {
Field[] fields = Class.class.getDeclaredFields0(false); // bypass caches
reflectionDataOffset = objectFieldOffset(fields, "reflectionData");
annotationTypeOffset = objectFieldOffset(fields, "annotationType");
annotationDataOffset = objectFieldOffset(fields, "annotationData");
}
private static long objectFieldOffset(Field[] fields, String fieldName) {
Field field = searchFields(fields, fieldName);
if (field == null) {
throw new Error("No " + fieldName + " field found in java.lang.Class");
}
return unsafe.objectFieldOffset(field);
}
static
* Few programmers will have any need for this method; it is provided
* for the benefit of the JRE itself. (It allows a class to determine at
* the time that it is initialized whether assertions should be enabled.)
* Note that this method is not guaranteed to return the actual
* assertion status that was (or will be) associated with the specified
* class when it was (or will be) initialized.
*
* @return the desired assertion status of the specified class.
* @see java.lang.ClassLoader#setClassAssertionStatus
* @see java.lang.ClassLoader#setPackageAssertionStatus
* @see java.lang.ClassLoader#setDefaultAssertionStatus
* @since 1.4
*/
public boolean desiredAssertionStatus() {
ClassLoader loader = getClassLoader();
// If the loader is null this is a system class, so ask the VM
if (loader == null)
return desiredAssertionStatus0(this);
// If the classloader has been initialized with the assertion
// directives, ask it. Otherwise, ask the VM.
synchronized(loader.assertionLock) {
if (loader.classAssertionStatus != null) {
return loader.desiredAssertionStatus(getName());
}
}
return desiredAssertionStatus0(this);
}
// Retrieves the desired assertion status of this class from the VM
private static native boolean desiredAssertionStatus0(Class clazz);
/**
* Returns true if and only if this class was declared as an enum in the
* source code.
*
* @return true if and only if this class was declared as an enum in the
* source code
* @since 1.5
*/
public boolean isEnum() {
// An enum must both directly extend java.lang.Enum and have
// the ENUM bit set; classes for specialized enum constants
// don't do the former.
return (this.getModifiers() & ENUM) != 0 &&
this.getSuperclass() == java.lang.Enum.class;
}
// Fetches the factory for reflective objects
private static ReflectionFactory getReflectionFactory() {
if (reflectionFactory == null) {
reflectionFactory =
java.security.AccessController.doPrivileged
(new sun.reflect.ReflectionFactory.GetReflectionFactoryAction());
}
return reflectionFactory;
}
private static ReflectionFactory reflectionFactory;
// To be able to query system properties as soon as they're available
private static boolean initted = false;
private static void checkInitted() {
if (initted) return;
AccessController.doPrivileged(new PrivilegedAction This method is useful when a client needs to "narrow" the type of
* a {@code Class} object to pass it to an API that restricts the
* {@code Class} objects that it is willing to accept. A cast would
* generate a compile-time warning, as the correctness of the cast
* could not be checked at runtime (because generic types are implemented
* by erasure).
*
* @param the type to cast this class object to
* @param clazz the class of the type to cast this class object to
* @return this {@code Class} object, cast to represent a subclass of
* the specified class object.
* @throws ClassCastException if this {@code Class} object does not
* represent a subclass of the specified class (here "subclass" includes
* the class itself).
* @since 1.5
*/
@SuppressWarnings("unchecked")
public Class asSubclass(Class clazz) {
if (clazz.isAssignableFrom(this))
return (Class) this;
else
throw new ClassCastException(this.toString());
}
/**
* @throws NullPointerException {@inheritDoc}
* @since 1.5
*/
@SuppressWarnings("unchecked")
public A getAnnotation(Class annotationClass) {
Objects.requireNonNull(annotationClass);
return (A) annotationData().annotations.get(annotationClass);
}
/**
* {@inheritDoc}
* @throws NullPointerException {@inheritDoc}
* @since 1.5
*/
@Override
public boolean isAnnotationPresent(Class annotationClass) {
return GenericDeclaration.super.isAnnotationPresent(annotationClass);
}
/**
* @throws NullPointerException {@inheritDoc}
* @since 1.8
*/
@Override
public A[] getAnnotationsByType(Class annotationClass) {
Objects.requireNonNull(annotationClass);
AnnotationData annotationData = annotationData();
return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
this,
annotationClass);
}
/**
* @since 1.5
*/
public Annotation[] getAnnotations() {
return AnnotationParser.toArray(annotationData().annotations);
}
/**
* @throws NullPointerException {@inheritDoc}
* @since 1.8
*/
@Override
@SuppressWarnings("unchecked")
public A getDeclaredAnnotation(Class annotationClass) {
Objects.requireNonNull(annotationClass);
return (A) annotationData().declaredAnnotations.get(annotationClass);
}
/**
* @throws NullPointerException {@inheritDoc}
* @since 1.8
*/
@Override
public A[] getDeclaredAnnotationsByType(Class annotationClass) {
Objects.requireNonNull(annotationClass);
return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
annotationClass);
}
/**
* @since 1.5
*/
public Annotation[] getDeclaredAnnotations() {
return AnnotationParser.toArray(annotationData().declaredAnnotations);
}
// annotation data that might get invalidated when JVM TI RedefineClasses() is called
private static class AnnotationData {
final Map If this {@code Class} object represents a type whose declaration
* does not explicitly indicate an annotated superclass, then the return
* value is an {@code AnnotatedType} object representing an element with no
* annotations.
*
* If this {@code Class} represents either the {@code Object} class, an
* interface type, an array type, a primitive type, or void, the return
* value is {@code null}.
*
* @return an object representing the superclass
* @since 1.8
*/
public AnnotatedType getAnnotatedSuperclass() {
if (this == Object.class ||
isInterface() ||
isArray() ||
isPrimitive() ||
this == Void.TYPE) {
return null;
}
return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
}
/**
* Returns an array of {@code AnnotatedType} objects that represent the use
* of types to specify superinterfaces of the entity represented by this
* {@code Class} object. (The use of type Foo to specify a
* superinterface in '... implements Foo' is distinct from the
* declaration of type Foo.)
*
* If this {@code Class} object represents a class, the return value is
* an array containing objects representing the uses of interface types to
* specify interfaces implemented by the class. The order of the objects in
* the array corresponds to the order of the interface types used in the
* 'implements' clause of the declaration of this {@code Class} object.
*
* If this {@code Class} object represents an interface, the return
* value is an array containing objects representing the uses of interface
* types to specify interfaces directly extended by the interface. The
* order of the objects in the array corresponds to the order of the
* interface types used in the 'extends' clause of the declaration of this
* {@code Class} object.
*
* If this {@code Class} object represents a class or interface whose
* declaration does not explicitly indicate any annotated superinterfaces,
* the return value is an array of length 0.
*
* If this {@code Class} object represents either the {@code Object}
* class, an array type, a primitive type, or void, the return value is an
* array of length 0.
*
* @return an array representing the superinterfaces
* @since 1.8
*/
public AnnotatedType[] getAnnotatedInterfaces() {
return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
}
}
*
*
*
Element Type Encoding
* boolean Z
* byte B
* char C
* class or interface
* Lclassname;
* double D
* float F
* int I
* long J
* short S
*
*
* @return the name of the class or interface
* represented by this object.
*/
public String getName() {
String name = this.name;
if (name == null)
this.name = name = getName0();
return name;
}
// cache the name to reduce the number of calls into the VM
private transient String name;
private native String getName0();
/**
* Returns the class loader for the class. Some implementations may use
* null to represent the bootstrap class loader. This method will return
* null in such implementations if this class was loaded by the bootstrap
* class loader.
*
*
* String.class.getName()
* returns "java.lang.String"
* byte.class.getName()
* returns "byte"
* (new Object[3]).getClass().getName()
* returns "[Ljava.lang.Object;"
* (new int[3][4][5][6][7][8][9]).getClass().getName()
* returns "[[[[[[[I"
*
* {@code class Shimmer implements FloorWax, DessertTopping { ... }}
*
* suppose the value of {@code s} is an instance of
* {@code Shimmer}; the value of the expression:
*
* {@code s.getClass().getInterfaces()[0]}
*
* is the {@code Class} object that represents interface
* {@code FloorWax}; and the value of:
*
* {@code s.getClass().getInterfaces()[1]}
*
* is the {@code Class} object that represents interface
* {@code DessertTopping}.
*
*
*
*
* @since 1.5
*/
@CallerSensitive
public Method getEnclosingMethod() throws SecurityException {
EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
if (enclosingInfo == null)
return null;
else {
if (!enclosingInfo.isMethod())
return null;
MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
getFactory());
Class returnType = toClass(typeInfo.getReturnType());
Type [] parameterTypes = typeInfo.getParameterTypes();
Class[] parameterClasses = new Class[parameterTypes.length];
// Convert Types to Classes; returned types *should*
// be class objects since the methodDescriptor's used
// don't have generics information
for(int i = 0; i < parameterClasses.length; i++)
parameterClasses[i] = toClass(parameterTypes[i]);
// Perform access check
Class enclosingCandidate = enclosingInfo.getEnclosingClass();
enclosingCandidate.checkMemberAccess(Member.DECLARED,
Reflection.getCallerClass(), true);
/*
* Loop over all declared methods; match method name,
* number of and type of parameters, *and* return
* type. Matching return type is also necessary
* because of covariant returns, etc.
*/
for(Method m: enclosingCandidate.getDeclaredMethods()) {
if (m.getName().equals(enclosingInfo.getName()) ) {
Class[] candidateParamClasses = m.getParameterTypes();
if (candidateParamClasses.length == parameterClasses.length) {
boolean matches = true;
for(int i = 0; i < candidateParamClasses.length; i++) {
if (!candidateParamClasses[i].equals(parameterClasses[i])) {
matches = false;
break;
}
}
if (matches) { // finally, check return type
if (m.getReturnType().equals(returnType) )
return m;
}
}
}
}
throw new InternalError("Enclosing method not found");
}
}
private native Object[] getEnclosingMethod0();
private EnclosingMethodInfo getEnclosingMethodInfo() {
Object[] enclosingInfo = getEnclosingMethod0();
if (enclosingInfo == null)
return null;
else {
return new EnclosingMethodInfo(enclosingInfo);
}
}
private final static class EnclosingMethodInfo {
private Class enclosingClass;
private String name;
private String descriptor;
private EnclosingMethodInfo(Object[] enclosingInfo) {
if (enclosingInfo.length != 3)
throw new InternalError("Malformed enclosing method information");
try {
// The array is expected to have three elements:
// the immediately enclosing class
enclosingClass = (Class) enclosingInfo[0];
assert(enclosingClass != null);
// the immediately enclosing method or constructor's
// name (can be null).
name = (String) enclosingInfo[1];
// the immediately enclosing method or constructor's
// descriptor (null iff name is).
descriptor = (String) enclosingInfo[2];
assert((name != null && descriptor != null) || name == descriptor);
} catch (ClassCastException cce) {
throw new InternalError("Invalid type in enclosing method information", cce);
}
}
boolean isPartial() {
return enclosingClass == null || name == null || descriptor == null;
}
boolean isConstructor() { return !isPartial() && "
*
*
* @since 1.5
*/
@CallerSensitive
public Constructor getEnclosingConstructor() throws SecurityException {
EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
if (enclosingInfo == null)
return null;
else {
if (!enclosingInfo.isConstructor())
return null;
ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
getFactory());
Type [] parameterTypes = typeInfo.getParameterTypes();
Class[] parameterClasses = new Class[parameterTypes.length];
// Convert Types to Classes; returned types *should*
// be class objects since the methodDescriptor's used
// don't have generics information
for(int i = 0; i < parameterClasses.length; i++)
parameterClasses[i] = toClass(parameterTypes[i]);
// Perform access check
Class enclosingCandidate = enclosingInfo.getEnclosingClass();
enclosingCandidate.checkMemberAccess(Member.DECLARED,
Reflection.getCallerClass(), true);
/*
* Loop over all declared constructors; match number
* of and type of parameters.
*/
for(Constructor c: enclosingCandidate.getDeclaredConstructors()) {
Class[] candidateParamClasses = c.getParameterTypes();
if (candidateParamClasses.length == parameterClasses.length) {
boolean matches = true;
for(int i = 0; i < candidateParamClasses.length; i++) {
if (!candidateParamClasses[i].equals(parameterClasses[i])) {
matches = false;
break;
}
}
if (matches)
return c;
}
}
throw new InternalError("Enclosing constructor not found");
}
}
/**
* If the class or interface represented by this {@code Class} object
* is a member of another class, returns the {@code Class} object
* representing the class in which it was declared. This method returns
* null if this class or interface is not a member of any other class. If
* this {@code Class} object represents an array class, a primitive
* type, or void,then this method returns null.
*
* @return the declaring class for this class
* @throws SecurityException
* If a security manager, s, is present and the caller's
* class loader is not the same as or an ancestor of the class
* loader for the declaring class and invocation of {@link
* SecurityManager#checkPackageAccess s.checkPackageAccess()}
* denies access to the package of the declaring class
* @since 1.1
*/
@CallerSensitive
public Class getDeclaringClass() throws SecurityException {
final Class candidate = getDeclaringClass0();
if (candidate != null)
candidate.checkPackageAccess(
ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
return candidate;
}
private native Class getDeclaringClass0();
/**
* Returns the immediately enclosing class of the underlying
* class. If the underlying class is a top level class this
* method returns {@code null}.
* @return the immediately enclosing class of the underlying class
* @exception SecurityException
* If a security manager, s, is present and the caller's
* class loader is not the same as or an ancestor of the class
* loader for the enclosing class and invocation of {@link
* SecurityManager#checkPackageAccess s.checkPackageAccess()}
* denies access to the package of the enclosing class
* @since 1.5
*/
@CallerSensitive
public Class getEnclosingClass() throws SecurityException {
// There are five kinds of classes (or interfaces):
// a) Top level classes
// b) Nested classes (static member classes)
// c) Inner classes (non-static member classes)
// d) Local classes (named classes declared within a method)
// e) Anonymous classes
// JVM Spec 4.8.6: A class must have an EnclosingMethod
// attribute if and only if it is a local class or an
// anonymous class.
EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
Class enclosingCandidate;
if (enclosingInfo == null) {
// This is a top level or a nested class or an inner class (a, b, or c)
enclosingCandidate = getDeclaringClass();
} else {
Class enclosingClass = enclosingInfo.getEnclosingClass();
// This is a local class or an anonymous class (d or e)
if (enclosingClass == this || enclosingClass == null)
throw new InternalError("Malformed enclosing method information");
else
enclosingCandidate = enclosingClass;
}
if (enclosingCandidate != null)
enclosingCandidate.checkPackageAccess(
ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
return enclosingCandidate;
}
/**
* Returns the simple name of the underlying class as given in the
* source code. Returns an empty string if the underlying class is
* anonymous.
*
*
*
*
*
*
*
*
*
*
*
*
* @since 1.1
*/
@CallerSensitive
public Class[] getDeclaredClasses() throws SecurityException {
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), false);
return getDeclaredClasses0();
}
/**
* Returns an array of {@code Field} objects reflecting all the fields
* declared by the class or interface represented by this
* {@code Class} object. This includes public, protected, default
* (package) access, and private fields, but excludes inherited fields.
*
*
*
*
*
* @since 1.1
* @jls 8.2 Class Members
* @jls 8.3 Field Declarations
*/
@CallerSensitive
public Field[] getDeclaredFields() throws SecurityException {
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
return copyFields(privateGetDeclaredFields(false));
}
/**
*
* Returns an array containing {@code Method} objects reflecting all the
* declared methods of the class or interface represented by this {@code
* Class} object, including public, protected, default (package)
* access, and private methods, but excluding inherited methods.
*
*
*
*
*
* @jls 8.2 Class Members
* @jls 8.4 Method Declarations
* @since 1.1
*/
@CallerSensitive
public Method[] getDeclaredMethods() throws SecurityException {
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
return copyMethods(privateGetDeclaredMethods(false));
}
/**
* Returns an array of {@code Constructor} objects reflecting all the
* constructors declared by the class represented by this
* {@code Class} object. These are public, protected, default
* (package) access, and private constructors. The elements in the array
* returned are not sorted and are not in any particular order. If the
* class has a default constructor, it is included in the returned array.
* This method returns an array of length 0 if this {@code Class}
* object represents an interface, a primitive type, an array class, or
* void.
*
*
*
*
*
* @since 1.1
*/
@CallerSensitive
public Constructor[] getDeclaredConstructors() throws SecurityException {
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
return copyConstructors(privateGetDeclaredConstructors(false));
}
/**
* Returns a {@code Field} object that reflects the specified declared
* field of the class or interface represented by this {@code Class}
* object. The {@code name} parameter is a {@code String} that specifies
* the simple name of the desired field.
*
*
*
*
*
* @since 1.1
* @jls 8.2 Class Members
* @jls 8.3 Field Declarations
*/
@CallerSensitive
public Field getDeclaredField(String name)
throws NoSuchFieldException, SecurityException {
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
Field field = searchFields(privateGetDeclaredFields(false), name);
if (field == null) {
throw new NoSuchFieldException(name);
}
return field;
}
/**
* Returns a {@code Method} object that reflects the specified
* declared method of the class or interface represented by this
* {@code Class} object. The {@code name} parameter is a
* {@code String} that specifies the simple name of the desired
* method, and the {@code parameterTypes} parameter is an array of
* {@code Class} objects that identify the method's formal parameter
* types, in declared order. If more than one method with the same
* parameter types is declared in a class, and one of these methods has a
* return type that is more specific than any of the others, that method is
* returned; otherwise one of the methods is chosen arbitrarily. If the
* name is "<init>"or "<clinit>" a {@code NoSuchMethodException}
* is raised.
*
*
*
*
*
* @jls 8.2 Class Members
* @jls 8.4 Method Declarations
* @since 1.1
*/
@CallerSensitive
public Method getDeclaredMethod(String name, Class... parameterTypes)
throws NoSuchMethodException, SecurityException {
checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
if (method == null) {
throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
}
return method;
}
/**
* Returns a {@code Constructor} object that reflects the specified
* constructor of the class or interface represented by this
* {@code Class} object. The {@code parameterTypes} parameter is
* an array of {@code Class} objects that identify the constructor's
* formal parameter types, in declared order.
*
* If this {@code Class} object represents an inner class
* declared in a non-static context, the formal parameter types
* include the explicit enclosing instance as the first parameter.
*
* @param parameterTypes the parameter array
* @return The {@code Constructor} object for the constructor with the
* specified parameter list
* @throws NoSuchMethodException if a matching method is not found.
* @throws SecurityException
* If a security manager, s, is present and any of the
* following conditions is met:
*
*
*
*
*
* @since 1.1
*/
@CallerSensitive
public Constructor
*
*
*
* @param name name of the desired resource
* @return A {@link java.io.InputStream} object or {@code null} if
* no resource with this name is found
* @throws NullPointerException If {@code name} is {@code null}
* @since 1.1
*/
public InputStream getResourceAsStream(String name) {
name = resolveName(name);
ClassLoader cl = getClassLoader0();
if (cl==null) {
// A system class.
return ClassLoader.getSystemResourceAsStream(name);
}
return cl.getResourceAsStream(name);
}
/**
* Finds a resource with a given name. The rules for searching resources
* associated with a given class are implemented by the defining
* {@linkplain ClassLoader class loader} of the class. This method
* delegates to this object's class loader. If this object was loaded by
* the bootstrap class loader, the method delegates to {@link
* ClassLoader#getSystemResource}.
*
*
* {@code modified_package_name/name}
*
*
*
*
*
*
* @param name name of the desired resource
* @return A {@link java.net.URL} object or {@code null} if no
* resource with this name is found
* @since 1.1
*/
public java.net.URL getResource(String name) {
name = resolveName(name);
ClassLoader cl = getClassLoader0();
if (cl==null) {
// A system class.
return ClassLoader.getSystemResource(name);
}
return cl.getResource(name);
}
/** protection domain returned when the internal domain is null */
private static java.security.ProtectionDomain allPermDomain;
/**
* Returns the {@code ProtectionDomain} of this class. If there is a
* security manager installed, this method first calls the security
* manager's {@code checkPermission} method with a
* {@code RuntimePermission("getProtectionDomain")} permission to
* ensure it's ok to get the
* {@code ProtectionDomain}.
*
* @return the ProtectionDomain of this class
*
* @throws SecurityException
* if a security manager exists and its
* {@code checkPermission} method doesn't allow
* getting the ProtectionDomain.
*
* @see java.security.ProtectionDomain
* @see SecurityManager#checkPermission
* @see java.lang.RuntimePermission
* @since 1.2
*/
public java.security.ProtectionDomain getProtectionDomain() {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
}
java.security.ProtectionDomain pd = getProtectionDomain0();
if (pd == null) {
if (allPermDomain == null) {
java.security.Permissions perms =
new java.security.Permissions();
perms.add(SecurityConstants.ALL_PERMISSION);
allPermDomain =
new java.security.ProtectionDomain(null, perms);
}
pd = allPermDomain;
}
return pd;
}
/**
* Returns the ProtectionDomain of this class.
*/
private native java.security.ProtectionDomain getProtectionDomain0();
/*
* Return the Virtual Machine's Class object for the named
* primitive type.
*/
static native Class getPrimitiveClass(String name);
/*
* Check if client is allowed to access members. If access is denied,
* throw a SecurityException.
*
* This method also enforces package access.
*
*
* {@code modified_package_name/name}
*
*
*
* {@code TC_CLASS} ClassDescriptor
* A ClassDescriptor is a special cased serialization of
* a {@code java.io.ObjectStreamClass} instance.
*
* A new handle is generated for the initial time the class descriptor
* is written into the stream. Future references to the class descriptor
* are written as references to the initial class descriptor instance.
*
* @see java.io.ObjectStreamClass
*/
private static final ObjectStreamField[] serialPersistentFields =
new ObjectStreamField[0];
/**
* Returns the assertion status that would be assigned to this
* class if it were to be initialized at the time this method is invoked.
* If this class has had its assertion status set, the most recent
* setting will be returned; otherwise, if any package default assertion
* status pertains to this class, the most recent setting for the most
* specific pertinent package default assertion status is returned;
* otherwise, if this class is not a system class (i.e., it has a
* class loader) its class loader's default assertion status is returned;
* otherwise, the system class default assertion status is returned.
*