/*
* @(#)Class.java 1.131 06/10/10
*
* Copyright 1990-2008 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 only, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is
* included at /legal/license.txt).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*
*/
package java.lang;
import java.lang.reflect.Member;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.lang.reflect.Constructor;
import java.lang.reflect.Modifier;
import java.lang.reflect.InvocationTargetException;
import java.io.InputStream;
import java.io.ObjectStreamClass;
import java.io.ObjectStreamField;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.ArrayList;
import java.util.List;
import sun.security.util.SecurityConstants;
import sun.misc.CVM;
import java.util.WeakHashMap;
import java.util.Map;
import java.util.Collections;
/**
* Instances of the class <code>Class</code> represent classes and interfaces
* in a running Java application. Every array also belongs to a class that is
* reflected as a <code>Class</code> object that is shared by all arrays with
* the same element type and number of dimensions. The primitive Java types
* (<code>boolean</code>, <code>byte</code>, <code>char</code>,
* <code>short</code>, <code>int</code>, <code>long</code>,
* <code>float</code>, and <code>double</code>), and the keyword
* <code>void</code> are also represented as <code>Class</code> objects.
*
* <p> <code>Class</code> has no public constructor. Instead <code>Class</code>
* objects are constructed automatically by the Java Virtual Machine as classes
* are loaded and by calls to the <code>defineClass</code> method in the class
* loader.
*
* <p> The following example uses a <code>Class</code> object to print the
* class name of an object:
*
* <p> <blockquote><pre>
* void printClassName(Object obj) {
* System.out.println("The class of " + obj +
* " is " + obj.getClass().getName());
* }
* </pre></blockquote>
*
* <p> It is also possible to get the <code>Class</code> object for a named
* type (or for void) using a class literal
* (JLS Section <A HREF="http://java.sun.com/docs/books/jls/second_edition/html/expressions.doc.html#251530">15.8.2</A>).
* For example:
*
* <p> <blockquote><pre>
* System.out.println("The name of class Foo is: "+Foo.class.getName());
* </pre></blockquote>
*
* @author unascribed
* @version 1.135, 05/25/01
* @see java.lang.ClassLoader#defineClass(byte[], int, int)
* @since JDK1.0
*/
public final
class Class implements java.io.Serializable {
private int classBlockPointer; /* Private pointer to cb */
private ClassLoader loader; /* For GC purposes only! */
/* No need to do this if ROMized
private static native void registerNatives();
static {
registerNatives();
}
*/
/*
* Constructor. Only the Java Virtual Machine creates Class
* objects.
*/
private Class() {}
/**
* Converts the object to a string. The string representation is the
* string "class" or "interface", followed by a space, and then by the
* fully qualified name of the class in the format returned by
* <code>getName</code>. If this <code>Class</code> object represents a
* primitive type, this method returns the name of the primitive type. If
* this <code>Class</code> object represents void this method returns
* "void".
*
* @return a string representation of this class object.
*/
public String toString() {
return (isInterface() ? "interface " : (isPrimitive() ? "" : "class "))
+ getName();
}
/**
* Returns the <code>Class</code> object associated with the class or
* interface with the given string name. Invoking this method is
* equivalent to:
*
* <blockquote><pre>
* Class.forName(className, true, currentLoader)
* </pre></blockquote>
*
* where <code>currentLoader</code> denotes the defining class loader of
* the current class.
*
* <p> For example, the following code fragment returns the
* runtime <code>Class</code> descriptor for the class named
* <code>java.lang.Thread</code>:
*
* <blockquote><pre>
* Class t = Class.forName("java.lang.Thread")
* </pre></blockquote>
* <p>
* A call to <tt>forName("X")</tt> causes the class named
* <tt>X</tt> to be initialized.
*
* @param className the fully qualified name of the desired class.
* @return the <code>Class</code> 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
*/
public static Class forName(String className)
throws ClassNotFoundException {
return forName0(className, true, ClassLoader.getCallerClassLoader());
}
/**
* Returns the <code>Class</code> 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</code>) 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</code> is null, the class is loaded through the bootstrap
* class loader. The class is initialized only if the
* <code>initialize</code> parameter is <code>true</code> and if it has
* not been initialized earlier.
*
* <p> If <code>name</code> 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</code>. Therefore, this method cannot be used to
* obtain any of the <code>Class</code> objects representing primitive
* types or void.
*
* <p> If <code>name</code> denotes an array class, the component type of
* the array class is loaded but not initialized.
*
* <p> For example, in an instance method the expression:
*
* <blockquote><pre>
* Class.forName("Foo")
* </pre></blockquote>
*
* is equivalent to:
*
* <blockquote><pre>
* Class.forName("Foo", true, this.getClass().getClassLoader())
* </pre></blockquote>
*
* Note that this method throws errors related to loading, linking or
* initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
* Java Language Specification</em>.
* Note that this method does not check whether the requested class
* is accessible to its caller.
*
* <p> If the <code>loader</code> is <code>null</code>, 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</code> method
* with a <code>RuntimePermission("getClassLoader")</code> permission to
* ensure it's ok to access the bootstrap class loader.
*
* @param name fully qualified name of the desired class
* @param initialize whether the class must be initialized
* @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
*/
public static Class forName(String name, boolean initialize,
ClassLoader loader)
throws ClassNotFoundException
{
if (loader == null) {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
ClassLoader ccl = ClassLoader.getCallerClassLoader();
if (ccl != null) {
sm.checkPermission(
SecurityConstants.GET_CLASSLOADER_PERMISSION);
}
}
}
return forName0(name, initialize, loader);
}
/** Called after security checks have been made. */
private static native Class forName0(String name, boolean initialize,
ClassLoader loader)
throws ClassNotFoundException;
/**
* Creates a new instance of the class represented by this <tt>Class</tt>
* object. The class is instantiated as if by a <code>new</code>
* expression with an empty argument list. The class is initialized if it
* has not already been initialized.
*
* <p>If there is a security manager, this method first calls the security
* manager's <code>checkMemberAccess</code> method with <code>this</code>
* and <code>Member.PUBLIC</code> as its arguments. If the class is in a
* package, then this method also calls the security manager's
* <code>checkPackageAccess</code> method with the package name as its
* argument. Either of these calls could result in a SecurityException.
*
* @return a newly allocated instance of the class represented by this
* object.
* @exception IllegalAccessException if the class or its nullary
* constructor is not accessible.
* @exception InstantiationException
* if this <code>Class</code> 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.
* @exception ExceptionInInitializerError if the initialization
* provoked by this method fails.
* @exception SecurityException if there is no permission to create a new
* instance.
*
*/
public Object newInstance()
throws InstantiationException, IllegalAccessException
{
if (System.getSecurityManager() != null) {
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
}
int flags = Modifier.ABSTRACT | Modifier.INTERFACE;
if ((getModifiers() & flags) != 0 || isPrimitive()) {
throw new InstantiationException(this.getName() +
" is an interface or abstract");
}
try {
CVM.setContextArtificial();
Constructor c = getConstructor0(new Class[0], Member.DECLARED);
return c.newInstance(new Object[0]);
} catch (NoSuchMethodException e) {
throw new InstantiationException(this.getName()+" has no appropriate constructor");
} catch (InvocationTargetException e) {
// There should be a better way! Maybe we need a
// private entry point to the Constructor.newInstance()
// implemenation that doesn't wrap things in
// InvocationTargetException
throw CVM.throwLocalException(e.getTargetException());
}
}
/**
* Determines if the specified <code>Object</code> is assignment-compatible
* with the object represented by this <code>Class</code>. This method is
* the dynamic equivalent of the Java language <code>instanceof</code>
* operator. The method returns <code>true</code> if the specified
* <code>Object</code> argument is non-null and can be cast to the
* reference type represented by this <code>Class</code> object without
* raising a <code>ClassCastException.</code> It returns <code>false</code>
* otherwise.
*
* <p> Specifically, if this <code>Class</code> object represents a
* declared class, this method returns <code>true</code> if the specified
* <code>Object</code> argument is an instance of the represented class (or
* of any of its subclasses); it returns <code>false</code> otherwise. If
* this <code>Class</code> object represents an array class, this method
* returns <code>true</code> if the specified <code>Object</code> 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</code> otherwise. If this <code>Class</code> object
* represents an interface, this method returns <code>true</code> if the
* class or any superclass of the specified <code>Object</code> argument
* implements this interface; it returns <code>false</code> otherwise. If
* this <code>Class</code> object represents a primitive type, this method
* returns <code>false</code>.
*
* @param obj the object to check
* @return true if <code>obj</code> is an instance of this class
*
* @since JDK1.1
*/
public native boolean isInstance(Object obj);
/**
* Determines if the class or interface represented by this
* <code>Class</code> object is either the same as, or is a superclass or
* superinterface of, the class or interface represented by the specified
* <code>Class</code> parameter. It returns <code>true</code> if so;
* otherwise it returns <code>false</code>. If this <code>Class</code>
* object represents a primitive type, this method returns
* <code>true</code> if the specified <code>Class</code> parameter is
* exactly this <code>Class</code> object; otherwise it returns
* <code>false</code>.
*
* <p> Specifically, this method tests whether the type represented by the
* specified <code>Class</code> parameter can be converted to the type
* represented by this <code>Class</code> object via an identity conversion
* or via a widening reference conversion. See <em>The Java Language
* Specification</em>, sections 5.1.1 and 5.1.4 , for details.
*
* @param cls the <code>Class</code> object to be checked
* @return the <code>boolean</code> value indicating whether objects of the
* type <code>cls</code> can be assigned to objects of this class
* @exception NullPointerException if the specified Class parameter is
* null.
* @since JDK1.1
*/
public native boolean isAssignableFrom(Class cls);
/**
* Determines if the specified <code>Class</code> object represents an
* interface type.
*
* @return <code>true</code> if this object represents an interface;
* <code>false</code> otherwise.
*/
public boolean isInterface() {
return Modifier.isInterface(getModifiers());
}
/**
* Determines if this <code>Class</code> object represents an array class.
*
* @return <code>true</code> if this object represents an array class;
* <code>false</code> otherwise.
* @since JDK1.1
*/
public native boolean isArray();
/**
* Determines if the specified <code>Class</code> object represents a
* primitive type.
*
* <p> There are nine predefined <code>Class</code> 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>, <code>byte</code>,
* <code>char</code>, <code>short</code>, <code>int</code>,
* <code>long</code>, <code>float</code>, and <code>double</code>.
*
* <p> These objects may only be accessed via the following public static
* final variables, and are the only <code>Class</code> objects for which
* this method returns <code>true</code>.
*
* @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 JDK1.1
*/
public native boolean isPrimitive();
/**
* Returns the name of the entity (class, interface, array class,
* primitive type, or void) represented by this <tt>Class</tt> object,
* as a <tt>String</tt>.
*
* <p> 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, Second Edition.
*
* <p> If this class object represents a primitive type or void, then the
* name returned is a <tt>String</tt> equal to the Java language
* keyword corresponding to the primitive type or void.
*
* <p> 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 '<tt>[</tt>' characters representing the depth of the array
* nesting. The encoding of element type names is as follows:
*
* <blockquote><table summary="Element types and encodings">
* <tr><th> Element Type <th> Encoding
* <tr><td> boolean <td align=center> Z
* <tr><td> byte <td align=center> B
* <tr><td> char <td align=center> C
* <tr><td> class or interface <td align=center> L<i>classname;</i>
* <tr><td> double <td align=center> D
* <tr><td> float <td align=center> F
* <tr><td> int <td align=center> I
* <tr><td> long <td align=center> J
* <tr><td> short <td align=center> S
* </table></blockquote>
*
* <p> The class or interface name <i>classname</i> is the binary name of
* the class specified above.
*
* <p> Examples:
* <blockquote><pre>
* 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"
* </pre></blockquote>
*
* @return the name of the class or interface
* represented by this object.
*/
public native String getName();
/**
* 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.
*
* <p> 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</code>
* method with a <code>RuntimePermission("getClassLoader")</code>
* permission to ensure it's ok to access the class loader for the class.
*
* <p>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</code> method denies
* access to the class loader for the class.
* @see java.lang.ClassLoader
* @see SecurityManager#checkPermission
* @see java.lang.RuntimePermission
*/
public ClassLoader getClassLoader() {
ClassLoader cl = getClassLoader0();
if (cl == null)
return null;
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
ClassLoader ccl = ClassLoader.getCallerClassLoader();
if (ccl != null && ccl != cl && !cl.isAncestor(ccl)) {
sm.checkPermission(SecurityConstants.GET_CLASSLOADER_PERMISSION);
}
}
return cl;
}
// Package-private to allow ClassLoader access
native ClassLoader getClassLoader0();
/**
* Returns the <code>Class</code> representing the superclass of the entity
* (class, interface, primitive type or void) represented by this
* <code>Class</code>. If this <code>Class</code> represents either the
* <code>Object</code> class, an interface, a primitive type, or void, then
* null is returned. If this object represents an array class then the
* <code>Class</code> object representing the <code>Object</code> class is
* returned.
*
* @return the superclass of the class represented by this object.
*/
public native Class 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.
*
* <p> 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);
}
/**
* Determines the interfaces implemented by the class or interface
* represented by this object.
*
* <p> If this object represents a class, the return value is an array
* containing objects representing all interfaces 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</code> clause
* of the declaration of the class represented by this object. For
* example, given the declaration:
* <blockquote><pre>
* class Shimmer implements FloorWax, DessertTopping { ... }
* </pre></blockquote>
* suppose the value of <code>s</code> is an instance of
* <code>Shimmer</code>; the value of the expression:
* <blockquote><pre>
* s.getClass().getInterfaces()[0]
* </pre></blockquote>
* is the <code>Class</code> object that represents interface
* <code>FloorWax</code>; and the value of:
* <blockquote><pre>
* s.getClass().getInterfaces()[1]
* </pre></blockquote>
* is the <code>Class</code> object that represents interface
* <code>DessertTopping</code>.
*
* <p> If this object represents an interface, the array contains objects
* representing all interfaces 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</code> clause of the declaration of the
* interface represented by this object.
*
* <p> If this object represents a class or interface that implements no
* interfaces, the method returns an array of length 0.
*
* <p> If this object represents a primitive type or void, the method
* returns an array of length 0.
*
* @return an array of interfaces implemented by this class.
*/
public native Class[] getInterfaces();
/**
* Returns the <code>Class</code> representing the component type of an
* array. If this class does not represent an array class this method
* returns null.
*
* @return the <code>Class</code> representing the component type of this
* class if this class is an array
* @see java.lang.reflect.Array
* @since JDK1.1
*/
public native Class getComponentType();
/**
* 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>, <code>protected</code>,
* <code>private</code>, <code>final</code>, <code>static</code>,
* <code>abstract</code> and <code>interface</code>; they should be decoded
* using the methods of class <code>Modifier</code>.
*
* <p> If the underlying class is an array class, then its
* <code>public</code>, <code>private</code> and <code>protected</code>
* modifiers are the same as those of its component type. If this
* <code>Class</code> represents a primitive type or void, its
* <code>public</code> modifier is always <code>true</code>, and its
* <code>protected</code> and <code>private</code> modifiers are always
* <code>false</code>. If this object represents an array class, a
* primitive type or void, then its <code>final</code> modifier is always
* <code>true</code> and its interface modifier is always
* <code>false</code>. The values of its other modifiers are not determined
* by this specification.
*
* <p> The modifier encodings are defined in <em>The Java Virtual Machine
* Specification</em>, table 4.1.
*
* @return the <code>int</code> representing the modifiers for this class
* @see java.lang.reflect.Modifier
* @since JDK1.1
*/
public native int getModifiers();
/* A private mapping of classes to their signers */
private static Map classToSigners;
private static void createClassToSignersMap() {
WeakHashMap map = new WeakHashMap(11);
Class.classToSigners = Collections.synchronizedMap(map);
}
/**
* 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 JDK1.1
*/
public Object[] getSigners() {
Object[] signers;
if (Class.classToSigners == null) {
Class.createClassToSignersMap();
}
signers = (Object[])Class.classToSigners.get(this);
if (signers == null) {
return null;
} else {
return (Object[])signers.clone();
}
}
/**
* Set the signers of this class.
*/
void setSigners(Object[] signers) {
if (Class.classToSigners == null) {
Class.createClassToSignersMap();
}
Class.classToSigners.put(this, signers);
}
/**
* If the class or interface represented by this <code>Class</code> object
* is a member of another class, returns the <code>Class</code> 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</code> object represents an array class, a primitive
* type, or void,then this method returns null.
*
* @return the declaring class for this class
* @since JDK1.1
*/
public native Class getDeclaringClass();
/**
* Returns an array containing <code>Class</code> objects representing all
* the public classes and interfaces that are members of the class
* represented by this <code>Class</code> 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</code> object has no public member
* classes or interfaces. This method also returns an array of length 0 if
* this <code>Class</code> object represents a primitive type, an array
* class, or void.
*
* <p>For this class and each of its superclasses, the following
* security checks are performed:
* If there is a security manager, the security manager's
* <code>checkMemberAccess</code> method is called with <code>this</code>
* and <code>Member.PUBLIC</code> as its arguments, where <code>this</code>
* is this class or the superclass whose members are being determined. If
* the class is in a package, then the security manager's
* <code>checkPackageAccess</code> method is also called with the package
* name as its argument. Either of these calls could result in a
* SecurityException.
*
* @return the array of <code>Class</code> objects representing the public
* members of this class
* @exception SecurityException if access to the information is denied.
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
*
* @since JDK1.1
*/
public Class[] getClasses() {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
// 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.
Class[] result = (Class[]) java.security.AccessController.doPrivileged
(new java.security.PrivilegedAction() {
public Object run() {
java.util.List list = new java.util.ArrayList();
Class currentClass = Class.this;
while (currentClass != null) {
Class[] members = currentClass.getDeclaredClasses();
for (int i = 0; i < members.length; i++) {
if (Modifier.isPublic(members[i].getModifiers())) {
list.add(members[i]);
}
}
currentClass = currentClass.getSuperclass();
}
return list.toArray(new Class[0]);
}
});
return result;
}
/**
* Returns an array containing <code>Field</code> objects reflecting all
* the accessible public fields of the class or interface represented by
* this <code>Class</code> object. The elements in the array returned are
* not sorted and are not in any particular order. This method returns an
* array of length 0 if the class or interface has no accessible public
* fields, or if it represents an array class, a primitive type, or void.
*
* <p> Specifically, if this <code>Class</code> object represents a class,
* this method returns the public fields of this class and of all its
* superclasses. If this <code>Class</code> object represents an
* interface, this method returns the fields of this interface and of all
* its superinterfaces.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.PUBLIC</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code>
* method with the package name as its argument. Either of these calls
* could result in a SecurityException.
*
* <p> The implicit length field for array class is not reflected by this
* method. User code should use the methods of class <code>Array</code> to
* manipulate arrays.
*
* <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3.
*
* @return the array of <code>Field</code> objects representing the
* public fields
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Field
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Field[] getFields() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
return getFields0(Member.PUBLIC);
}
/**
* Returns an array containing <code>Method</code> objects reflecting all
* the public <em>member</em> methods of the class or interface represented
* by this <code>Class</code> object, including those declared by the class
* or interface and and those inherited from superclasses and
* superinterfaces. The elements in the array returned are not sorted and
* are not in any particular order. This method returns an array of length
* 0 if this <code>Class</code> object represents a class or interface that
* has no public member methods, or if this <code>Class</code> object
* represents an array class, primitive type, or void.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.PUBLIC</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code>
* method with the package name
* as its argument. Either of these calls could result in a SecurityException.
*
* <p> The class initialization method <code><clinit></code> is not
* included in the returned array. If the class declares multiple public
* member methods with the same parameter types, they are all included in
* the returned array.
*
* <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.4.
*
* @return the array of <code>Method</code> objects representing the
* public methods of this class
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Method
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Method[] getMethods() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
return getMethods0(Member.PUBLIC);
}
/**
* Returns an array containing <code>Constructor</code> objects reflecting
* all the public constructors of the class represented by this
* <code>Class</code> 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.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.PUBLIC</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code>
* method with the package name
* as its argument. Either of these calls could result in a SecurityException.
*
* @return the array containing <code>Method</code> objects for all the
* declared public constructors of this class matches the specified
* <code>parameterTypes</code>
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Constructor
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Constructor[] getConstructors() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
return getConstructors0(Member.PUBLIC);
}
/**
* Returns a <code>Field</code> object that reflects the specified public
* member field of the class or interface represented by this
* <code>Class</code> object. The <code>name</code> parameter is a
* <code>String</code> specifying the simple name of the desired field.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.PUBLIC</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code>
* method with the package name
* as its argument. Either of these calls could result in a SecurityException.
*
* <p> The field to be reflected is determined by the algorithm that
* follows. Let C be the class represented by this object:
* <OL>
* <LI> If C declares a public field with the name specified, that is the
* field to be reflected.</LI>
* <LI> If no field was found in step 1 above, this algorithm is applied
* recursively to each direct superinterface of C. The direct
* superinterfaces are searched in the order they were declared.</LI>
* <LI> If no field was found in steps 1 and 2 above, and C has a
* superclass S, then this algorithm is invoked recursively upon S.
* If C has no superclass, then a <code>NoSuchFieldException</code>
* is thrown.</LI>
* </OL>
*
* <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3.
*
* @param name the field name
* @return the <code>Field</code> object of this class specified by
* <code>name</code>
* @exception NoSuchFieldException if a field with the specified name is
* not found.
* @exception NullPointerException if <code>name</code> is <code>null</code>
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Field
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Field getField(String name)
throws NoSuchFieldException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
return getField0(name, Member.PUBLIC);
}
/**
* Returns a <code>Method</code> object that reflects the specified public
* member method of the class or interface represented by this
* <code>Class</code> object. The <code>name</code> parameter is a
* <code>String</code> specifying the simple name the desired method. The
* <code>parameterTypes</code> parameter is an array of <code>Class</code>
* objects that identify the method's formal parameter types, in declared
* order. If <code>parameterTypes</code> is <code>null</code>, it is
* treated as if it were an empty array.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.PUBLIC</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code>
* method with the package name
* as its argument. Either of these calls could result in a SecurityException.
*
* <p> If the <code>name</code> is "<init>"or "<clinit>" a
* <code>NoSuchMethodException</code> is raised. Otherwise, the method to
* be reflected is determined by the algorithm that follows. Let C be the
* class represented by this object:
* <OL>
* <LI> C is searched for any <I>matching methods</I>. If no matching
* method is found, the algorithm of step 1 is invoked recursively on
* the superclass of C.</LI>
* <LI> If no method was found in step 1 above, the superinterfaces of C
* are searched for a matching method. If any such method is found, it
* is reflected.</LI>
* </OL>
*
* To find a matching method in a class 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.
*
* <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.4.
*
* @param name the name of the method
* @param parameterTypes the list of parameters
* @return the <code>Method</code> object that matches the specified
* <code>name</code> and <code>parameterTypes</code>
* @exception NoSuchMethodException if a matching method is not found
* or if the name is "<init>"or "<clinit>".
* @exception NullPointerException if <code>name</code> is <code>null</code>
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Method
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Method getMethod(String name, Class[] parameterTypes)
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
return getMethod0(name, parameterTypes, Member.PUBLIC);
}
/**
* Returns a <code>Constructor</code> object that reflects the specified
* public constructor of the class represented by this <code>Class</code>
* object. The <code>parameterTypes</code> parameter is an array of
* <code>Class</code> objects that identify the constructor's formal
* parameter types, in declared order.
*
* <p> The constructor to reflect is the public constructor of the class
* represented by this <code>Class</code> object whose formal parameter
* types match those specified by <code>parameterTypes</code>.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.PUBLIC</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code> method
* with the package name as its argument. Either of these calls could
* result in a SecurityException.
*
* @param parameterTypes the parameter array
* @return the <code>Method</code> object of the public constructor that
* matches the specified <code>parameterTypes</code>
* @exception NoSuchMethodException if a matching method is not found.
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Constructor
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Constructor getConstructor(Class[] parameterTypes)
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.PUBLIC, ClassLoader.getCallerClassLoader());
return getConstructor0(parameterTypes, Member.PUBLIC);
}
/**
* Returns an array of <code>Class</code> objects reflecting all the
* classes and interfaces declared as members of the class represented by
* this <code>Class</code> object. This includes public, protected, default
* (package) access, and private classes and interfaces declared by the
* class, but excludes inherited classes and interfaces. This method
* returns an array of length 0 if the class declares no classes or
* interfaces as members, or if this <code>Class</code> object represents a
* primitive type, an array class, or void.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.DECLARED</code>
* as its arguments. If the class is in a package, then this method also
* calls the security manager's <code>checkPackageAccess</code> method with
* the package name as its argument. Either of these calls could result in
* a SecurityException.
*
* @return the array of <code>Class</code> objects representing all the
* declared members of this class
* @exception SecurityException if access to the information is denied.
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Class[] getDeclaredClasses() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
return getDeclaredClasses0();
}
/**
* Returns an array of <code>Field</code> objects reflecting all the fields
* declared by the class or interface represented by this
* <code>Class</code> object. This includes public, protected, default
* (package) access, and private fields, but excludes inherited fields.
* The elements in the array returned are not sorted and are not in any
* particular order. This method returns an array of length 0 if the class
* or interface declares no fields, or if this <code>Class</code> object
* represents a primitive type, an array class, or void.
*
* <p> See <em>The Java Language Specification</em>, sections 8.2 and 8.3.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method with
* <code>this</code> and <code>Member.DECLARED</code> as its arguments. If
* the class is in a package, then this method also calls the security
* manager's <code>checkPackageAccess</code> method with the package name
* as its argument. Either of these calls could result in a
* SecurityException.
*
* @return the array of <code>Field</code> objects representing all the
* declared fields of this class
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Field
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Field[] getDeclaredFields() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
return getFields0(Member.DECLARED);
}
/**
* Returns an array of <code>Method</code> objects reflecting all the
* methods declared by the class or interface represented by this
* <code>Class</code> object. This includes public, protected, default
* (package) access, and private methods, but excludes inherited methods.
* The elements in the array returned are not sorted and are not in any
* particular order. This method returns an array of length 0 if the class
* or interface declares no methods, or if this <code>Class</code> object
* represents a primitive type, an array class, or void. The class
* initialization method <code><clinit></code> is not included in the
* returned array. If the class declares multiple public member methods
* with the same parameter types, they are all included in the returned
* array.
*
* <p> See <em>The Java Language Specification</em>, section 8.2.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.DECLARED</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code> method
* with the package name as its argument. Either of these calls could
* result in a SecurityException.
*
* @return the array of <code>Method</code> objects representing all the
* declared methods of this class
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Method
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Method[] getDeclaredMethods() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
return getMethods0(Member.DECLARED);
}
/**
* Returns an array of <code>Constructor</code> objects reflecting all the
* constructors declared by the class represented by this
* <code>Class</code> 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</code>
* object represents an interface, a primitive type, an array class, or
* void.
*
* <p> See <em>The Java Language Specification</em>, section 8.2.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.DECLARED</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code> method
* with the package name as its argument. Either of these calls could
* result in a SecurityException.
*
* @return the array of <code>Method</code> objects representing all the
* declared constructors of this class
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Constructor
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Constructor[] getDeclaredConstructors() throws SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
return getConstructors0(Member.DECLARED);
}
/**
* Returns a <code>Field</code> object that reflects the specified declared
* field of the class or interface represented by this <code>Class</code>
* object. The <code>name</code> parameter is a <code>String</code> that
* specifies the simple name of the desired field. Note that this method
* will not reflect the <code>length</code> field of an array class.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.DECLARED</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code> method
* with the package name as its argument. Either of these calls could
* result in a SecurityException.
*
* @param name the name of the field
* @return the <code>Field</code> object for the specified field in this
* class
* @exception NoSuchFieldException if a field with the specified name is
* not found.
* @exception NullPointerException if <code>name</code> is <code>null</code>
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Field
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Field getDeclaredField(String name)
throws NoSuchFieldException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
return getField0(name, Member.DECLARED);
}
/**
* Returns a <code>Method</code> object that reflects the specified
* declared method of the class or interface represented by this
* <code>Class</code> object. The <code>name</code> parameter is a
* <code>String</code> that specifies the simple name of the desired
* method, and the <code>parameterTypes</code> parameter is an array of
* <code>Class</code> 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</code>
* is raised.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.DECLARED</code>
* as its arguments. If the class is in a package, then this method also
* calls the security manager's <code>checkPackageAccess</code> method with
* the package name as its argument. Either of these calls could result in
* a SecurityException.
*
* @param name the name of the method
* @param parameterTypes the parameter array
* @return the <code>Method</code> object for the method of this class
* matching the specified name and parameters
* @exception NoSuchMethodException if a matching method is not found.
* @exception NullPointerException if <code>name</code> is <code>null</code>
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Method
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Method getDeclaredMethod(String name, Class[] parameterTypes)
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
return getMethod0(name, parameterTypes, Member.DECLARED);
}
/**
* Returns a <code>Constructor</code> object that reflects the specified
* constructor of the class or interface represented by this
* <code>Class</code> object. The <code>parameterTypes</code> parameter is
* an array of <code>Class</code> objects that identify the constructor's
* formal parameter types, in declared order.
*
* <p>If there is a security manager, this method first
* calls the security manager's <code>checkMemberAccess</code> method
* with <code>this</code> and <code>Member.DECLARED</code>
* as its arguments. If the class is in a package, then this method
* also calls the security manager's <code>checkPackageAccess</code>
* method with the package name
* as its argument. Either of these calls could result in a SecurityException.
*
* @param parameterTypes the parameter array
* @return The <code>Method</code> object for the constructor with the
* specified parameter list
* @exception NoSuchMethodException if a matching method is not found.
* @exception SecurityException if access to the information is denied.
* @see java.lang.reflect.Constructor
* @see SecurityManager#checkMemberAccess(Class, int)
* @see SecurityManager#checkPackageAccess(String)
* @since JDK1.1
*/
public Constructor getDeclaredConstructor(Class[] parameterTypes)
throws NoSuchMethodException, SecurityException {
// be very careful not to change the stack depth of this
// checkMemberAccess call for security reasons
// see java.lang.SecurityManager.checkMemberAccess
checkMemberAccess(Member.DECLARED, ClassLoader.getCallerClassLoader());
return getConstructor0(parameterTypes, Member.DECLARED);
}
/**
* Finds a resource with a given name. This method returns null if no
* resource with this name is found. The rules for searching
* resources associated with a given class are implemented by the
* defining class loader of the class.
*
* <p> This method delegates the call to its class loader, after making
* these changes to the resource name: if the resource name starts with
* "/", it is unchanged; otherwise, the package name is prepended to the
* resource name after converting "." to "/". If this object was loaded by
* the bootstrap loader, the call is delegated to
* <code>ClassLoader.getSystemResourceAsStream</code>.
*
* @param name name of the desired resource
* @return a <code>java.io.InputStream</code> object.
* @throws NullPointerException if <code>name</code> is <code>null</code>.
* @see java.lang.ClassLoader
* @since JDK1.1
*/
public InputStream getResourceAsStream(String name) {
ClassLoader cl;
name = resolveName(name);
if (CVM.callerIsMidlet()) {
/*
* This is work around for the many MIDlet's that expect that
* calling getResouresAsStream on a *system* class such as
* java.lang.String class will get a resources out of the
* MIDlet's JAR.
*
* The MIDP spec says that a MIDlet can only get resources
* from its JAR when it calls Class.getResourceAsStream(), it
* meant "midlet".getClass().getResourceAsStream().
*
* The MIDP TCK tests for the positive case using the class of the
* test case. The TCK should also test for a negative case of
* String.getResourceAsStream, but it does not. System classes
* for CLDC VMs search the application class path for resources
* and will get resources from a MIDlet's JAR on the class path.
*
* We only want this work around for MIDlets not the MIDP
* implemention code (which should be able to get any resource).
*/
cl = ClassLoader.getCallerClassLoader();
} else {
cl = getClassLoader0();
}
if (cl==null) {
// This is system class.
return ClassLoader.getSystemResourceAsStream(name);
}
return cl.getResourceAsStream(name);
}
/**
* Finds a resource with a given name. This method returns null if no
* resource with this name is found. The rules for searching resources
* associated with a given class are implemented by the * defining class
* loader of the class.
*
* <p> This method delegates the call to its class loader, after making
* these changes to the resource name: if the resource name starts with
* "/", it is unchanged; otherwise, the package name is prepended to the
* resource name after converting "." to "/". If this object was loaded by
* the bootstrap loader, the call is delegated to
* <code>ClassLoader.getSystemResource</code>.
*
* @param name name of the desired resource
* @return a <code>java.net.URL</code> object.
* @see java.lang.ClassLoader
* @since JDK1.1
*/
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</code> of this class. If there is a
* security manager installed, this method first calls the security
* manager's <code>checkPermission</code> method with a
* <code>RuntimePermission("getProtectionDomain")</code> permission to
* ensure it's ok to get the
* <code>ProtectionDomain</code>.
*
* @return the ProtectionDomain of this class
*
* @throws SecurityException
* if a security manager exists and its
* <code>checkPermission</code> 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.
*
* Be very careful not to change the stack depth of this checkMemberAccess
* call for security reasons reasons see
* java.lang.SecurityManager.checkMemberAccess
*
* <p> Default policy: allow all clients access with normal Java access
* control.
*/
private void checkMemberAccess(int which, ClassLoader ccl) {
SecurityManager s = System.getSecurityManager();
if (s != null) {
s.checkMemberAccess(this, which);
ClassLoader cl = getClassLoader0();
if ((ccl != null) && (ccl != cl) &&
((cl == null) || !cl.isAncestor(ccl))) {
String name = this.getName();
int i = name.lastIndexOf('.');
if (i != -1) {
s.checkPackageAccess(name.substring(0, i));
}
}
}
}
/**
* 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;
}
/**
* Reflection support.
*/
private native Field[] getFields0(int which);
private native Method[] getMethods0(int which);
private native Constructor[] getConstructors0(int which);
private native Field getField0(String name, int which);
private native Method getMethod0(String name, Class[] parameterTypes,
int which);
private native Constructor getConstructor0(Class[] parameterTypes,
int which) throws NoSuchMethodException;
private native Class[] getDeclaredClasses0();
/** use serialVersionUID from JDK 1.1 for interoperability */
private static final long serialVersionUID = 3206093459760846163L;
/**
* Class Class is special cased within the Serialization Stream Protocol.
*
* A Class instance is written intially into an ObjectOutputStream in the
* following format:
* <pre>
* <code>TC_CLASS</code> ClassDescriptor
* A ClassDescriptor is a special cased serialization of
* a <code>java.io.ObjectStreamClass</code> instance.
* </pre>
* 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 =
ObjectStreamClass.NO_FIELDS;
/**
* 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.
* <p>
* 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);
synchronized(loader) {
// If the classloader has been initialized with
// the assertion directives, ask it. Otherwise,
// ask the VM.
return (loader.classAssertionStatus == null ?
desiredAssertionStatus0(this) :
loader.desiredAssertionStatus(getName()));
}
}
// Retrieves the desired assertion status of this class from the VM
private static native boolean desiredAssertionStatus0(Class clazz);
private native boolean checkInitializedFlag();
private native boolean checkInitializingFlag(boolean me);
private native boolean checkErrorFlag();
private native void setInitializedFlag();
private native void setInitializingFlag();
private native void setErrorFlag();
private native void clearInitializingFlag();
private native void clearSuperClassesLoadedFlag();
/* put <this,loader> in the loader cache */
native void addToLoaderCache(ClassLoader loader);
/* the following are only useable during loadSuperClasses(). */
private native int getClassTypeID();
native boolean superClassesLoaded();
private native int getSuperClassTypeID();
private native String getSuperClassName(ClassLoader loader);
private native int getNumInterfaces();
private native int getInterfaceTypeID(int index);
private native String getInterfaceName(int index, ClassLoader loader);
private native void linkSuperClasses();
private native void notifyClassLoaded();
private void runStaticInitializers() throws Throwable {
CVM.disableRemoteExceptions();
boolean unmask = !CVM.maskInterrupts();
try {
/* Step 1 - lock the class. */
synchronized (this) {
/* Step 2 - if someone is currenly initializing this class
* and it's not our thread, then wait until the class is
* done initializing. */
while (checkInitializingFlag(false)) {
try {
wait(0);
} catch (InterruptedException e) {
/* This can't happen since async exceptions are
* disabled during static intializers.
*/
}
}
/* Step 3 and 4 - return success if this thread is
* initializing the class or if the class is already
* initialized. */
if (checkInitializingFlag(true) || checkInitializedFlag()) {
return;
}
/* Step 5 - fail if class is already in an erroneous state. */
if (checkErrorFlag()) {
throw new NoClassDefFoundError(getName());
}
/* Step 6 - mark the class as "initializing" and unlock it. */
setInitializingFlag();
}
/* Step 7 - run the superclass static initialzer. */
Class superClass = getSuperclass();
if (superClass != null && !superClass.checkInitializedFlag()) {
try {
superClass.runStaticInitializers();
} catch (Throwable e) {
synchronized (this) {
clearInitializingFlag();
setErrorFlag();
notifyAll();
}
throw e;
}
}
/* Step 8 - run the static intializer. */
Throwable clinitError = null;
try {
CVM.executeClinit(this);
} catch (Throwable e) {
clinitError = e;
}
/* free up memory used by the <clinit> method */
CVM.freeClinit(this);
/* Step 9 - no exception thrown. */
if (clinitError == null) {
synchronized (this) {
clearInitializingFlag();
setInitializedFlag();
notifyAll();
return;
}
}
/* Step 10 - an exception was thrown. If it is not an instance of
* Error, then change it to ExceptionInInitializerError. */
if (!(clinitError instanceof Error)) {
try {
clinitError = new ExceptionInInitializerError(clinitError);
} catch (Throwable e) {
clinitError = e;
}
}
/* Step 11 - error out the class and throw the exception */
synchronized (this) {
clearInitializingFlag();
setErrorFlag();
notifyAll();
}
throw clinitError;
} finally {
if (unmask) {
CVM.unmaskInterrupts();
}
CVM.enableRemoteExceptions();
}
};
/*
* class LoadingList
*
* Used to maintain a list of classes whose superclasses are
* currently being loaded so we can easily check for class
* circularities. Since the list uses <typeid,loader> pairs,
* there's no need to keep a separate list for each ClassLoader
* instance and for the NULL classloader.
*/
private static class LoadingList {
int typeID;
ClassLoader loader;
LoadingList next;
LoadingList(int typeID, ClassLoader loader, LoadingList next) {
this.typeID = typeID;
this.loader = loader;
this.next = next;
}
}
private static LoadingList loadingList;
private boolean onLoadingList(int typeID) {
synchronized(LoadingList.class) {
LoadingList item = loadingList;
while (item != null) {
if (item.typeID == typeID && item.loader == loader) {
return true;
}
item = item.next;
}
}
return false;
}
private void addToLoadingList() {
int typeID = getClassTypeID();
if (onLoadingList(typeID))
throw new ClassCircularityError(getName());
synchronized(LoadingList.class) {
loadingList = new LoadingList(typeID, loader, loadingList);
}
}
private void removeFromLoadingList() {
synchronized(LoadingList.class) {
int typeID = getClassTypeID();
LoadingList item = loadingList;
LoadingList prevItem = null;
while (item != null) {
if (item.typeID == typeID && item.loader == loader) {
if (prevItem == null) {
loadingList = item.next;
} else {
prevItem.next = item.next;
}
return;
}
prevItem = item;
item = item.next;
}
}
}
/*
* Load all the superclasses and interfaces in a way that doesn't
* cause any C recursion, only java recursion.
*/
void loadSuperClasses() {
/* Name and typeid of the class to load. The class is
* either the superclass of the current class, or one
* of its superinterfaces. */
String clName = null;
int clTypeID = -1;
try {
addToLoadingList(); /* check for class circularities */
/* Make sure the superclasses are loaded. */
/* Returns NULL if class is already in the loader cache */
clName = getSuperClassName(loader);
if (clName != null) {
clTypeID = getSuperClassTypeID();
if (loader == null) {
ClassLoader.loadBootstrapClass(clName);
} else {
Class c = loader.loadClass(clName);
/*
* It's possible that the class is not in the loaderCache.
* This happens when the class is loaded by the parent
* of "loader". Class.linkSuperClasses() requires that the
* class be in the loaderCache, so we load it here.
*/
if (c.loader != loader) {
c.addToLoaderCache(loader);
}
}
}
/* make sure the interfaces are loaded */
int numInterfaces = getNumInterfaces();
for (int i = 0; i < numInterfaces; i++) {
/* Returns NULL if class is already in the loader cache */
clName = getInterfaceName(i, loader);
if (clName != null) {
clTypeID = getInterfaceTypeID(i);
if (loader == null) {
ClassLoader.loadBootstrapClass(clName);
} else {
Class c = loader.loadClass(clName);
/* See comment for similar code above. */
if (c.loader != loader) {
c.addToLoaderCache(loader);
}
}
}
}
/*
* All super classes are now loaded, so we can link this
* class to it's super class. has to be done before
* calling ClassLoader.addClass(). Otherwise, if
* CVMclassLinkSuperClasses() failed, the ClassLoader
* instance would have access to an invalid class. There
* is an invariant that any Class instance obtained by
* java code must already have its superclasses
* loaded. Otherwise the vm can crash.
*/
linkSuperClasses();
/* It is now safe to put the class in the loader cache. */
addToLoaderCache(loader);
/* add the class to its ClassLoader so it won't get gc'd */
if (loader != null) {
boolean success = false;
try {
loader.addClass(this);
success = true;
} finally {
if (!success) {
/* prevent loaderCache lookup */
setErrorFlag();
clearSuperClassesLoadedFlag();
}
}
}
} catch (ClassNotFoundException e) {
if (onLoadingList(clTypeID)) {
throw new ClassCircularityError(clName);
} else {
throw new NoClassDefFoundError(e.getMessage());
}
} finally {
removeFromLoadingList();
}
notifyClassLoaded();
}
}