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Diffstat (limited to 'libjava/java/lang/Class.java')
| -rw-r--r-- | libjava/java/lang/Class.java | 1430 |
1 files changed, 0 insertions, 1430 deletions
diff --git a/libjava/java/lang/Class.java b/libjava/java/lang/Class.java deleted file mode 100644 index a4e8ee5..0000000 --- a/libjava/java/lang/Class.java +++ /dev/null @@ -1,1430 +0,0 @@ -/* Class.java -- Representation of a Java class. - Copyright (C) 1998, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007 - Free Software Foundation - -This file is part of GNU Classpath. - -GNU Classpath is free software; you can redistribute it and/or modify -it under the terms of the GNU General Public License as published by -the Free Software Foundation; either version 2, or (at your option) -any later version. - -GNU Classpath 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 for more details. - -You should have received a copy of the GNU General Public License -along with GNU Classpath; see the file COPYING. If not, write to the -Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA -02110-1301 USA. - -Linking this library statically or dynamically with other modules is -making a combined work based on this library. Thus, the terms and -conditions of the GNU General Public License cover the whole -combination. - -As a special exception, the copyright holders of this library give you -permission to link this library with independent modules to produce an -executable, regardless of the license terms of these independent -modules, and to copy and distribute the resulting executable under -terms of your choice, provided that you also meet, for each linked -independent module, the terms and conditions of the license of that -module. An independent module is a module which is not derived from -or based on this library. If you modify this library, you may extend -this exception to your version of the library, but you are not -obligated to do so. If you do not wish to do so, delete this -exception statement from your version. */ - -package java.lang; - -import gnu.java.lang.reflect.ClassSignatureParser; -import java.io.InputStream; -import java.io.Serializable; -import java.lang.annotation.Annotation; -import java.lang.reflect.Constructor; -import java.lang.reflect.Field; -import java.lang.reflect.GenericDeclaration; -import java.lang.reflect.InvocationTargetException; -import java.lang.reflect.Member; -import java.lang.reflect.Method; -import java.lang.reflect.Type; -import java.lang.reflect.TypeVariable; -import java.net.URL; -import java.security.AccessController; -import java.security.PrivilegedAction; -import java.security.ProtectionDomain; -import java.util.ArrayList; -import java.util.Arrays; -import java.util.LinkedHashSet; -import java.util.HashMap; -import java.util.Collection; -import java.lang.reflect.AnnotatedElement; -import java.lang.annotation.Annotation; -import java.lang.annotation.Inherited; -import java.lang.reflect.AccessibleObject; - -/** - * A Class represents a Java type. There will never be multiple Class - * objects with identical names and ClassLoaders. Primitive types, array - * types, and void also have a Class object. - * - * <p>Arrays with identical type and number of dimensions share the same class. - * The array class ClassLoader is the same as the ClassLoader of the element - * type of the array (which can be null to indicate the bootstrap classloader). - * The name of an array class is <code>[<signature format>;</code>. - * <p> For example, - * String[]'s class is <code>[Ljava.lang.String;</code>. boolean, byte, - * short, char, int, long, float and double have the "type name" of - * Z,B,S,C,I,J,F,D for the purposes of array classes. If it's a - * multidimensioned array, the same principle applies: - * <code>int[][][]</code> == <code>[[[I</code>. - * - * <p>There is no public constructor - Class objects are obtained only through - * the virtual machine, as defined in ClassLoaders. - * - * @serialData Class objects serialize specially: - * <code>TC_CLASS ClassDescriptor</code>. For more serialization information, - * see {@link ObjectStreamClass}. - * - * @author John Keiser - * @author Eric Blake (ebb9@email.byu.edu) - * @author Tom Tromey (tromey@cygnus.com) - * @since 1.0 - * @see ClassLoader - */ -public final class Class<T> - implements Type, AnnotatedElement, GenericDeclaration, Serializable -{ - /** - * Class is non-instantiable from Java code; only the VM can create - * instances of this class. - */ - private Class () - { - } - - // Initialize the class. - private native void initializeClass (); - - // finalization - protected native void finalize () throws Throwable; - - /** - * Use the classloader of the current class to load, link, and initialize - * a class. This is equivalent to your code calling - * <code>Class.forName(name, true, getClass().getClassLoader())</code>. - * - * @param name the name of the class to find - * @return the Class object representing the class - * @throws ClassNotFoundException if the class was not found by the - * classloader - * @throws LinkageError if linking the class fails - * @throws ExceptionInInitializerError if the class loads, but an exception - * occurs during initialization - */ - public static native Class<?> forName (String className) - throws ClassNotFoundException; - - // A private internal method that is called by compiler-generated code. - private static Class forName (String className, Class caller) - throws ClassNotFoundException - { - return forName(className, true, caller.getClassLoaderInternal()); - } - - - /** - * Use the specified classloader to load and link a class. If the loader - * is null, this uses the bootstrap class loader (provide the security - * check succeeds). Unfortunately, this method cannot be used to obtain - * the Class objects for primitive types or for void, you have to use - * the fields in the appropriate java.lang wrapper classes. - * - * <p>Calls <code>classloader.loadclass(name, initialize)</code>. - * - * @param name the name of the class to find - * @param initialize whether or not to initialize the class at this time - * @param classloader the classloader to use to find the class; null means - * to use the bootstrap class loader - * @throws ClassNotFoundException if the class was not found by the - * classloader - * @throws LinkageError if linking the class fails - * @throws ExceptionInInitializerError if the class loads, but an exception - * occurs during initialization - * @throws SecurityException if the <code>classloader</code> argument - * is <code>null</code> and the caller does not have the - * <code>RuntimePermission("getClassLoader")</code> permission - * @see ClassLoader - * @since 1.2 - */ - public static native Class<?> forName (String className, boolean initialize, - ClassLoader loader) - throws ClassNotFoundException; - - /** - * Get all the public member classes and interfaces declared in this - * class or inherited from superclasses. This returns an array of length - * 0 if there are no member classes, including for primitive types. A - * security check may be performed, with - * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @return all public member classes in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public Class<?>[] getClasses() - { - memberAccessCheck(Member.PUBLIC); - return internalGetClasses(); - } - - /** - * Like <code>getClasses()</code> but without the security checks. - */ - private Class<?>[] internalGetClasses() - { - ArrayList<Class> list = new ArrayList<Class>(); - list.addAll(Arrays.asList(getDeclaredClasses(true))); - Class superClass = getSuperclass(); - if (superClass != null) - list.addAll(Arrays.asList(superClass.internalGetClasses())); - return list.toArray(new Class<?>[list.size()]); - } - - /** - * Get the ClassLoader that loaded this class. If the class was loaded - * by the bootstrap classloader, this method will return null. - * If there is a security manager, and the caller's class loader is not - * an ancestor of the requested one, a security check of - * <code>RuntimePermission("getClassLoader")</code> - * must first succeed. Primitive types and void return null. - * - * @return the ClassLoader that loaded this class - * @throws SecurityException if the security check fails - * @see ClassLoader - * @see RuntimePermission - */ - public native ClassLoader getClassLoader (); - - // A private internal method that is called by compiler-generated code. - private final native ClassLoader getClassLoader (Class caller); - - /** - * Internal method that circumvents the usual security checks when - * getting the class loader. - */ - private native ClassLoader getClassLoaderInternal (); - - /** - * If this is an array, get the Class representing the type of array. - * Examples: "[[Ljava.lang.String;" would return "[Ljava.lang.String;", and - * calling getComponentType on that would give "java.lang.String". If - * this is not an array, returns null. - * - * @return the array type of this class, or null - * @see Array - * @since 1.1 - */ - public native Class<?> getComponentType (); - - /** - * Get a public constructor declared in this class. If the constructor takes - * no argument, an array of zero elements and null are equivalent for the - * types argument. A security check may be performed, with - * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @param types the type of each parameter - * @return the constructor - * @throws NoSuchMethodException if the constructor does not exist - * @throws SecurityException if the security check fails - * @see #getConstructors() - * @since 1.1 - */ - public native Constructor<T> getConstructor(Class<?>... args) - throws NoSuchMethodException; - - /** - * Get all the public constructors of this class. This returns an array of - * length 0 if there are no constructors, including for primitive types, - * arrays, and interfaces. It does, however, include the default - * constructor if one was supplied by the compiler. A security check may - * be performed, with <code>checkMemberAccess(this, Member.PUBLIC)</code> - * as well as <code>checkPackageAccess</code> both having to succeed. - * - * @return all public constructors in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public Constructor<?>[] getConstructors() - { - memberAccessCheck(Member.PUBLIC); - return getDeclaredConstructors(true); - } - - /** - * Get a constructor declared in this class. If the constructor takes no - * argument, an array of zero elements and null are equivalent for the - * types argument. A security check may be performed, with - * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @param types the type of each parameter - * @return the constructor - * @throws NoSuchMethodException if the constructor does not exist - * @throws SecurityException if the security check fails - * @see #getDeclaredConstructors() - * @since 1.1 - */ - public native Constructor<T> getDeclaredConstructor(Class<?>... args) - throws NoSuchMethodException; - - /** - * Get all the declared member classes and interfaces in this class, but - * not those inherited from superclasses. This returns an array of length - * 0 if there are no member classes, including for primitive types. A - * security check may be performed, with - * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @return all declared member classes in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public Class<?>[] getDeclaredClasses() - { - memberAccessCheck(Member.DECLARED); - return getDeclaredClasses(false); - } - - native Class<?>[] getDeclaredClasses (boolean publicOnly); - - /** - * Get all the declared constructors of this class. This returns an array of - * length 0 if there are no constructors, including for primitive types, - * arrays, and interfaces. It does, however, include the default - * constructor if one was supplied by the compiler. A security check may - * be performed, with <code>checkMemberAccess(this, Member.DECLARED)</code> - * as well as <code>checkPackageAccess</code> both having to succeed. - * - * @return all constructors in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public Constructor<?>[] getDeclaredConstructors() - { - memberAccessCheck(Member.DECLARED); - return getDeclaredConstructors(false); - } - - native Constructor<?>[] getDeclaredConstructors (boolean publicOnly); - - /** - * Get a field declared in this class, where name is its simple name. The - * implicit length field of arrays is not available. A security check may - * be performed, with <code>checkMemberAccess(this, Member.DECLARED)</code> - * as well as <code>checkPackageAccess</code> both having to succeed. - * - * @param name the name of the field - * @return the field - * @throws NoSuchFieldException if the field does not exist - * @throws SecurityException if the security check fails - * @see #getDeclaredFields() - * @since 1.1 - */ - public native Field getDeclaredField(String fieldName) - throws NoSuchFieldException; - - /** - * Get all the declared fields in this class, but not those inherited from - * superclasses. This returns an array of length 0 if there are no fields, - * including for primitive types. This does not return the implicit length - * field of arrays. A security check may be performed, with - * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @return all declared fields in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public Field[] getDeclaredFields() - { - memberAccessCheck(Member.DECLARED); - return getDeclaredFields(false); - } - - native Field[] getDeclaredFields (boolean publicOnly); - - private native Method _getDeclaredMethod(String methodName, Class[] args); - - /** - * Get a method declared in this class, where name is its simple name. The - * implicit methods of Object are not available from arrays or interfaces. - * Constructors (named "<init>" in the class file) and class initializers - * (name "<clinit>") are not available. The Virtual Machine allows - * multiple methods with the same signature but differing return types; in - * such a case the most specific return types are favored, then the final - * choice is arbitrary. If the method takes no argument, an array of zero - * elements and null are equivalent for the types argument. A security - * check may be performed, with - * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @param methodName the name of the method - * @param types the type of each parameter - * @return the method - * @throws NoSuchMethodException if the method does not exist - * @throws SecurityException if the security check fails - * @see #getDeclaredMethods() - * @since 1.1 - */ - public Method getDeclaredMethod(String methodName, Class<?>... args) - throws NoSuchMethodException - { - memberAccessCheck(Member.DECLARED); - - if ("<init>".equals(methodName) || "<clinit>".equals(methodName)) - throw new NoSuchMethodException(methodName); - - Method match = _getDeclaredMethod(methodName, args); - if (match == null) - throw new NoSuchMethodException(methodName); - return match; - } - - /** - * Get all the declared methods in this class, but not those inherited from - * superclasses. This returns an array of length 0 if there are no methods, - * including for primitive types. This does include the implicit methods of - * arrays and interfaces which mirror methods of Object, nor does it - * include constructors or the class initialization methods. The Virtual - * Machine allows multiple methods with the same signature but differing - * return types; all such methods are in the returned array. A security - * check may be performed, with - * <code>checkMemberAccess(this, Member.DECLARED)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @return all declared methods in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public native Method[] getDeclaredMethods(); - - /** - * If this is a nested or inner class, return the class that declared it. - * If not, return null. - * - * @return the declaring class of this class - * @since 1.1 - */ - // This is marked as unimplemented in the JCL book. - public native Class<?> getDeclaringClass (); - - private native Field getField (String fieldName, int hash) - throws NoSuchFieldException; - - /** - * Get a public field declared or inherited in this class, where name is - * its simple name. If the class contains multiple accessible fields by - * that name, an arbitrary one is returned. The implicit length field of - * arrays is not available. A security check may be performed, with - * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @param fieldName the name of the field - * @return the field - * @throws NoSuchFieldException if the field does not exist - * @throws SecurityException if the security check fails - * @see #getFields() - * @since 1.1 - */ - public Field getField(String fieldName) - throws NoSuchFieldException - { - memberAccessCheck(Member.PUBLIC); - Field field = getField(fieldName, fieldName.hashCode()); - if (field == null) - throw new NoSuchFieldException(fieldName); - return field; - } - - /** - * Get all the public fields declared in this class or inherited from - * superclasses. This returns an array of length 0 if there are no fields, - * including for primitive types. This does not return the implicit length - * field of arrays. A security check may be performed, with - * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @return all public fields in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public Field[] getFields() - { - memberAccessCheck(Member.PUBLIC); - return internalGetFields(); - } - - /** - * Like <code>getFields()</code> but without the security checks. - */ - private Field[] internalGetFields() - { - LinkedHashSet set = new LinkedHashSet(); - set.addAll(Arrays.asList(getDeclaredFields(true))); - Class[] interfaces = getInterfaces(); - for (int i = 0; i < interfaces.length; i++) - set.addAll(Arrays.asList(interfaces[i].internalGetFields())); - Class superClass = getSuperclass(); - if (superClass != null) - set.addAll(Arrays.asList(superClass.internalGetFields())); - return (Field[])set.toArray(new Field[set.size()]); - } - - /** - * Returns the <code>Package</code> in which this class is defined - * Returns null when this information is not available from the - * classloader of this class. - * - * @return the package for this class, if it is available - * @since 1.2 - */ - public Package getPackage() - { - ClassLoader cl = getClassLoaderInternal(); - if (cl != null) - return cl.getPackage(getPackagePortion(getName())); - else - return VMClassLoader.getPackage(getPackagePortion(getName())); - } - - /** - * Get the interfaces this class <em>directly</em> implements, in the - * order that they were declared. This returns an empty array, not null, - * for Object, primitives, void, and classes or interfaces with no direct - * superinterface. Array types return Cloneable and Serializable. - * - * @return the interfaces this class directly implements - */ - public native Class<?>[] getInterfaces (); - - private final native void getSignature(StringBuffer buffer); - private static final native String getSignature(Class[] args, - boolean is_construtor); - - public native Method _getMethod(String methodName, Class[] args); - - /** - * Get a public method declared or inherited in this class, where name is - * its simple name. The implicit methods of Object are not available from - * interfaces. Constructors (named "<init>" in the class file) and class - * initializers (name "<clinit>") are not available. The Virtual - * Machine allows multiple methods with the same signature but differing - * return types, and the class can inherit multiple methods of the same - * return type; in such a case the most specific return types are favored, - * then the final choice is arbitrary. If the method takes no argument, an - * array of zero elements and null are equivalent for the types argument. - * A security check may be performed, with - * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @param methodName the name of the method - * @param types the type of each parameter - * @return the method - * @throws NoSuchMethodException if the method does not exist - * @throws SecurityException if the security check fails - * @see #getMethods() - * @since 1.1 - */ - public Method getMethod(String methodName, Class<?>... args) - throws NoSuchMethodException - { - memberAccessCheck(Member.PUBLIC); - - if ("<init>".equals(methodName) || "<clinit>".equals(methodName)) - throw new NoSuchMethodException(methodName); - - Method method = _getMethod(methodName, args); - if (method == null) - throw new NoSuchMethodException(methodName); - return method; - } - - private native int _getMethods (Method[] result, int offset); - - /** - * Get all the public methods declared in this class or inherited from - * superclasses. This returns an array of length 0 if there are no methods, - * including for primitive types. This does not include the implicit - * methods of interfaces which mirror methods of Object, nor does it - * include constructors or the class initialization methods. The Virtual - * Machine allows multiple methods with the same signature but differing - * return types; all such methods are in the returned array. A security - * check may be performed, with - * <code>checkMemberAccess(this, Member.PUBLIC)</code> as well as - * <code>checkPackageAccess</code> both having to succeed. - * - * @return all public methods in this class - * @throws SecurityException if the security check fails - * @since 1.1 - */ - public native Method[] getMethods(); - - /** - * Get the modifiers of this class. These can be decoded using Modifier, - * and is limited to one of public, protected, or private, and any of - * final, static, abstract, or interface. An array class has the same - * public, protected, or private modifier as its component type, and is - * marked final but not an interface. Primitive types and void are marked - * public and final, but not an interface. - * - * @return the modifiers of this class - * @see Modifer - * @since 1.1 - */ - public native int getModifiers (); - - /** - * Get the name of this class, separated by dots for package separators. - * If the class represents a primitive type, or void, then the - * name of the type as it appears in the Java programming language - * is returned. For instance, <code>Byte.TYPE.getName()</code> - * returns "byte". - * - * Arrays are specially encoded as shown on this table. - * <pre> - * array type [<em>element type</em> - * (note that the element type is encoded per - * this table) - * boolean Z - * byte B - * char C - * short S - * int I - * long J - * float F - * double D - * void V - * class or interface, alone: <dotted name> - * class or interface, as element type: L<dotted name>; - * </pre> - * - * @return the name of this class - */ - public native String getName (); - - /** - * Get a resource URL using this class's package using the - * getClassLoader().getResource() method. If this class was loaded using - * the system classloader, ClassLoader.getSystemResource() is used instead. - * - * <p>If the name you supply is absolute (it starts with a <code>/</code>), - * then the leading <code>/</code> is removed and it is passed on to - * getResource(). If it is relative, the package name is prepended, and - * <code>.</code>'s are replaced with <code>/</code>. - * - * <p>The URL returned is system- and classloader-dependent, and could - * change across implementations. - * - * @param resourceName the name of the resource, generally a path - * @return the URL to the resource - * @throws NullPointerException if name is null - * @since 1.1 - */ - public URL getResource(String resourceName) - { - String name = resourcePath(resourceName); - ClassLoader loader = getClassLoaderInternal(); - if (loader == null) - return ClassLoader.getSystemResource(name); - return loader.getResource(name); - } - - /** - * Get a resource using this class's package using the - * getClassLoader().getResourceAsStream() method. If this class was loaded - * using the system classloader, ClassLoader.getSystemResource() is used - * instead. - * - * <p>If the name you supply is absolute (it starts with a <code>/</code>), - * then the leading <code>/</code> is removed and it is passed on to - * getResource(). If it is relative, the package name is prepended, and - * <code>.</code>'s are replaced with <code>/</code>. - * - * <p>The URL returned is system- and classloader-dependent, and could - * change across implementations. - * - * @param resourceName the name of the resource, generally a path - * @return an InputStream with the contents of the resource in it, or null - * @throws NullPointerException if name is null - * @since 1.1 - */ - public InputStream getResourceAsStream(String resourceName) - { - String name = resourcePath(resourceName); - ClassLoader loader = getClassLoaderInternal(); - if (loader == null) - return ClassLoader.getSystemResourceAsStream(name); - return loader.getResourceAsStream(name); - } - - private String resourcePath(String resourceName) - { - if (resourceName.length() > 0) - { - if (resourceName.charAt(0) != '/') - { - String pkg = getPackagePortion(getName()); - if (pkg.length() > 0) - resourceName = pkg.replace('.','/') + '/' + resourceName; - } - else - { - resourceName = resourceName.substring(1); - } - } - return resourceName; - } - - /** - * Get the signers of this class. This returns null if there are no signers, - * such as for primitive types or void. - * - * @return the signers of this class - * @since 1.1 - */ - public native Object[] getSigners (); - - /** - * Set the signers of this class. - * - * @param signers the signers of this class - */ - native void setSigners(Object[] signers); - - /** - * Get the direct superclass of this class. If this is an interface, - * Object, a primitive type, or void, it will return null. If this is an - * array type, it will return Object. - * - * @return the direct superclass of this class - */ - public native Class<? super T> getSuperclass (); - - /** - * Return whether this class is an array type. - * - * @return whether this class is an array type - * @since 1.1 - */ - public native boolean isArray (); - - /** - * Discover whether an instance of the Class parameter would be an - * instance of this Class as well. Think of doing - * <code>isInstance(c.newInstance())</code> or even - * <code>c.newInstance() instanceof (this class)</code>. While this - * checks widening conversions for objects, it must be exact for primitive - * types. - * - * @param c the class to check - * @return whether an instance of c would be an instance of this class - * as well - * @throws NullPointerException if c is null - * @since 1.1 - */ - public native boolean isAssignableFrom (Class<?> c); - - /** - * Discover whether an Object is an instance of this Class. Think of it - * as almost like <code>o instanceof (this class)</code>. - * - * @param o the Object to check - * @return whether o is an instance of this class - * @since 1.1 - */ - public native boolean isInstance (Object o); - - /** - * Check whether this class is an interface or not. Array types are not - * interfaces. - * - * @return whether this class is an interface or not - */ - public native boolean isInterface (); - - /** - * Return whether this class is a primitive type. A primitive type class - * is a class representing a kind of "placeholder" for the various - * primitive types, or void. You can access the various primitive type - * classes through java.lang.Boolean.TYPE, java.lang.Integer.TYPE, etc., - * or through boolean.class, int.class, etc. - * - * @return whether this class is a primitive type - * @see Boolean#TYPE - * @see Byte#TYPE - * @see Character#TYPE - * @see Short#TYPE - * @see Integer#TYPE - * @see Long#TYPE - * @see Float#TYPE - * @see Double#TYPE - * @see Void#TYPE - * @since 1.1 - */ - public native boolean isPrimitive (); - - /** - * Get a new instance of this class by calling the no-argument constructor. - * The class is initialized if it has not been already. A security check - * may be performed, with <code>checkMemberAccess(this, Member.PUBLIC)</code> - * as well as <code>checkPackageAccess</code> both having to succeed. - * - * @return a new instance of this class - * @throws InstantiationException if there is not a no-arg constructor - * for this class, including interfaces, abstract classes, arrays, - * primitive types, and void; or if an exception occurred during - * the constructor - * @throws IllegalAccessException if you are not allowed to access the - * no-arg constructor because of scoping reasons - * @throws SecurityException if the security check fails - * @throws ExceptionInInitializerError if class initialization caused by - * this call fails with an exception - */ - public native T newInstance () - throws InstantiationException, IllegalAccessException; - - // We need a native method to retrieve the protection domain, because we - // can't add fields to java.lang.Class that are accessible from Java. - private native ProtectionDomain getProtectionDomain0(); - - /** - * Returns the protection domain of this class. If the classloader did not - * record the protection domain when creating this class the unknown - * protection domain is returned which has a <code>null</code> code source - * and all permissions. A security check may be performed, with - * <code>RuntimePermission("getProtectionDomain")</code>. - * - * @return the protection domain - * @throws SecurityException if the security manager exists and the caller - * does not have <code>RuntimePermission("getProtectionDomain")</code>. - * @see RuntimePermission - * @since 1.2 - */ - public ProtectionDomain getProtectionDomain() - { - SecurityManager sm = System.getSecurityManager(); - if (sm != null) - sm.checkPermission(VMClassLoader.protectionDomainPermission); - - ProtectionDomain protectionDomain = getProtectionDomain0(); - - if (protectionDomain == null) - return VMClassLoader.unknownProtectionDomain; - else - return protectionDomain; - } - - /** - * Return the human-readable form of this Object. For an object, this - * is either "interface " or "class " followed by <code>getName()</code>, - * for primitive types and void it is just <code>getName()</code>. - * - * @return the human-readable form of this Object - */ - public String toString() - { - if (isPrimitive()) - return getName(); - return (isInterface() ? "interface " : "class ") + getName(); - } - - /** - * Returns the desired assertion status of this class, if it were to be - * initialized at this moment. The class assertion status, if set, is - * returned; the backup is the default package status; then if there is - * a class loader, that default is returned; and finally the system default - * is returned. This method seldom needs calling in user code, but exists - * for compilers to implement the assert statement. Note that there is no - * guarantee that the result of this method matches the class's actual - * assertion status. - * - * @return the desired assertion status - * @see ClassLoader#setClassAssertionStatus(String, boolean) - * @see ClassLoader#setPackageAssertionStatus(String, boolean) - * @see ClassLoader#setDefaultAssertionStatus(boolean) - * @since 1.4 - */ - public boolean desiredAssertionStatus() - { - ClassLoader c = getClassLoaderInternal(); - Object status; - if (c == null) - return VMClassLoader.defaultAssertionStatus(); - if (c.classAssertionStatus != null) - synchronized (c) - { - status = c.classAssertionStatus.get(getName()); - if (status != null) - return status.equals(Boolean.TRUE); - } - else - { - status = ClassLoader.systemClassAssertionStatus.get(getName()); - if (status != null) - return status.equals(Boolean.TRUE); - } - if (c.packageAssertionStatus != null) - synchronized (c) - { - String name = getPackagePortion(getName()); - if ("".equals(name)) - status = c.packageAssertionStatus.get(null); - else - do - { - status = c.packageAssertionStatus.get(name); - name = getPackagePortion(name); - } - while (! "".equals(name) && status == null); - if (status != null) - return status.equals(Boolean.TRUE); - } - else - { - String name = getPackagePortion(getName()); - if ("".equals(name)) - status = ClassLoader.systemPackageAssertionStatus.get(null); - else - do - { - status = ClassLoader.systemPackageAssertionStatus.get(name); - name = getPackagePortion(name); - } - while (! "".equals(name) && status == null); - if (status != null) - return status.equals(Boolean.TRUE); - } - return c.defaultAssertionStatus; - } - - /** - * Strip the last portion of the name (after the last dot). - * - * @param name the name to get package of - * @return the package name, or "" if no package - */ - private static String getPackagePortion(String name) - { - int lastInd = name.lastIndexOf('.'); - if (lastInd == -1) - return ""; - return name.substring(0, lastInd); - } - - /** - * Perform security checks common to all of the methods that - * get members of this Class. - */ - private void memberAccessCheck(int which) - { - SecurityManager sm = System.getSecurityManager(); - if (sm != null) - { - sm.checkMemberAccess(this, which); - Package pkg = getPackage(); - if (pkg != null) - sm.checkPackageAccess(pkg.getName()); - } - } - - - /** - * <p> - * Casts this class to represent a subclass of the specified class. - * This method is useful for `narrowing' the type of a class so that - * the class object, and instances of that class, can match the contract - * of a more restrictive method. For example, if this class has the - * static type of <code>Class<Object></code>, and a dynamic type of - * <code>Class<Rectangle></code>, then, assuming <code>Shape</code> is - * a superclass of <code>Rectangle</code>, this method can be used on - * this class with the parameter, <code>Class<Shape></code>, to retain - * the same instance but with the type - * <code>Class<? extends Shape></code>. - * </p> - * <p> - * If this class can be converted to an instance which is parameterised - * over a subtype of the supplied type, <code>U</code>, then this method - * returns an appropriately cast reference to this object. Otherwise, - * a <code>ClassCastException</code> is thrown. - * </p> - * - * @param klass the class object, the parameterized type (<code>U</code>) of - * which should be a superclass of the parameterized type of - * this instance. - * @return a reference to this object, appropriately cast. - * @throws ClassCastException if this class can not be converted to one - * which represents a subclass of the specified - * type, <code>U</code>. - * @since 1.5 - */ - public <U> Class<? extends U> asSubclass(Class<U> klass) - { - if (! klass.isAssignableFrom(this)) - throw new ClassCastException(); - return (Class<? extends U>) this; - } - - /** - * Returns the specified object, cast to this <code>Class</code>' type. - * - * @param obj the object to cast - * @throws ClassCastException if obj is not an instance of this class - * @since 1.5 - */ - public T cast(Object obj) - { - if (obj != null && ! isInstance(obj)) - throw new ClassCastException(); - return (T) obj; - } - - /** - * Returns the enumeration constants of this class, or - * null if this class is not an <code>Enum</code>. - * - * @return an array of <code>Enum</code> constants - * associated with this class, or null if this - * class is not an <code>enum</code>. - * @since 1.5 - */ - public T[] getEnumConstants() - { - if (isEnum()) - { - try - { - Method m = getMethod("values"); - setAccessible(m); - return (T[]) m.invoke(null); - } - catch (NoSuchMethodException exception) - { - throw new Error("Enum lacks values() method"); - } - catch (IllegalAccessException exception) - { - throw new Error("Unable to access Enum class"); - } - catch (InvocationTargetException exception) - { - throw new - RuntimeException("The values method threw an exception", - exception); - } - } - else - { - return null; - } - } - - /** - * Returns true if this class is an <code>Enum</code>. - * - * @return true if this is an enumeration class. - * @since 1.5 - */ - public native boolean isEnum(); - - - /** - * Returns true if this class is a synthetic class, generated by - * the compiler. - * - * @return true if this is a synthetic class. - * @since 1.5 - */ - public native boolean isSynthetic(); - - - /** - * Returns true if this class is an <code>Annotation</code>. - * - * @return true if this is an annotation class. - * @since 1.5 - */ - public native boolean isAnnotation(); - - - /** - * Returns the simple name for this class, as used in the source - * code. For normal classes, this is the content returned by - * <code>getName()</code> which follows the last ".". Anonymous - * classes have no name, and so the result of calling this method is - * "". The simple name of an array consists of the simple name of - * its component type, followed by "[]". Thus, an array with the - * component type of an anonymous class has a simple name of simply - * "[]". - * - * @return the simple name for this class. - * @since 1.5 - */ - public String getSimpleName() - { - if (isAnonymousClass()) - return ""; - if (isArray()) - return getComponentType().getSimpleName() + "[]"; - - String fullName = getName(); - Class enclosingClass = getEnclosingClass(); - if (enclosingClass == null) - // It's a top level class. - return fullName.substring(fullName.lastIndexOf(".") + 1); - - fullName = fullName.substring(enclosingClass.getName().length()); - - // We've carved off the enclosing class name; now we must have '$' - // followed optionally by digits, followed by the class name. - int pos = 1; - while (Character.isDigit(fullName.charAt(pos))) - ++pos; - fullName = fullName.substring(pos); - - return fullName; - } - - /** - * Returns the class which immediately encloses this class. If this class - * is a top-level class, this method returns <code>null</code>. - * - * @return the immediate enclosing class, or <code>null</code> if this is - * a top-level class. - * @since 1.5 - */ - public native Class<?> getEnclosingClass(); - - /** - * Returns the constructor which immediately encloses this class. If - * this class is a top-level class, or a local or anonymous class - * immediately enclosed by a type definition, instance initializer - * or static initializer, then <code>null</code> is returned. - * - * @return the immediate enclosing constructor if this class is - * declared within a constructor. Otherwise, <code>null</code> - * is returned. - * @since 1.5 - */ - public native Constructor<T> getEnclosingConstructor(); - - /** - * Returns the method which immediately encloses this class. If - * this class is a top-level class, or a local or anonymous class - * immediately enclosed by a type definition, instance initializer - * or static initializer, then <code>null</code> is returned. - * - * @return the immediate enclosing method if this class is - * declared within a method. Otherwise, <code>null</code> - * is returned. - * @since 1.5 - */ - public native Method getEnclosingMethod(); - - private native String getClassSignature(); - - /** - * <p> - * Returns an array of <code>Type</code> objects which represent the - * interfaces directly implemented by this class or extended by this - * interface. - * </p> - * <p> - * If one of the superinterfaces is a parameterized type, then the - * object returned for this interface reflects the actual type - * parameters used in the source code. Type parameters are created - * using the semantics specified by the <code>ParameterizedType</code> - * interface, and only if an instance has not already been created. - * </p> - * <p> - * The order of the interfaces in the array matches the order in which - * the interfaces are declared. For classes which represent an array, - * an array of two interfaces, <code>Cloneable</code> and - * <code>Serializable</code>, is always returned, with the objects in - * that order. A class representing a primitive type or void always - * returns an array of zero size. - * </p> - * - * @return an array of interfaces implemented or extended by this class. - * @throws GenericSignatureFormatError if the generic signature of one - * of the interfaces does not comply with that specified by the Java - * Virtual Machine specification, 3rd edition. - * @throws TypeNotPresentException if any of the superinterfaces refers - * to a non-existant type. - * @throws MalformedParameterizedTypeException if any of the interfaces - * refer to a parameterized type that can not be instantiated for - * some reason. - * @since 1.5 - * @see java.lang.reflect.ParameterizedType - */ - public Type[] getGenericInterfaces() - { - if (isPrimitive()) - return new Type[0]; - - String sig = getClassSignature(); - if (sig == null) - return getInterfaces(); - - ClassSignatureParser p = new ClassSignatureParser(this, sig); - return p.getInterfaceTypes(); - } - - /** - * <p> - * Returns a <code>Type</code> object representing the direct superclass, - * whether class, interface, primitive type or void, of this class. - * If this class is an array class, then a class instance representing - * the <code>Object</code> class is returned. If this class is primitive, - * an interface, or a representation of either the <code>Object</code> - * class or void, then <code>null</code> is returned. - * </p> - * <p> - * If the superclass is a parameterized type, then the - * object returned for this interface reflects the actual type - * parameters used in the source code. Type parameters are created - * using the semantics specified by the <code>ParameterizedType</code> - * interface, and only if an instance has not already been created. - * </p> - * - * @return the superclass of this class. - * @throws GenericSignatureFormatError if the generic signature of the - * class does not comply with that specified by the Java - * Virtual Machine specification, 3rd edition. - * @throws TypeNotPresentException if the superclass refers - * to a non-existant type. - * @throws MalformedParameterizedTypeException if the superclass - * refers to a parameterized type that can not be instantiated for - * some reason. - * @since 1.5 - * @see java.lang.reflect.ParameterizedType - */ - public Type getGenericSuperclass() - { - if (isArray()) - return Object.class; - - if (isPrimitive() || isInterface() || this == Object.class) - return null; - - String sig = getClassSignature(); - if (sig == null) - return getSuperclass(); - - ClassSignatureParser p = new ClassSignatureParser(this, sig); - return p.getSuperclassType(); - } - - /** - * Returns an array of <code>TypeVariable</code> objects that represents - * the type variables declared by this class, in declaration order. - * An array of size zero is returned if this class has no type - * variables. - * - * @return the type variables associated with this class. - * @throws GenericSignatureFormatError if the generic signature does - * not conform to the format specified in the Virtual Machine - * specification, version 3. - * @since 1.5 - */ - public TypeVariable<Class<T>>[] getTypeParameters() - { - String sig = getClassSignature(); - if (sig == null) - return (TypeVariable<Class<T>>[])new TypeVariable[0]; - - ClassSignatureParser p = new ClassSignatureParser(this, sig); - return p.getTypeParameters(); - } - - /** - * Returns this class' annotation for the specified annotation type, - * or <code>null</code> if no such annotation exists. - * - * @param annotationClass the type of annotation to look for. - * @return this class' annotation for the specified type, or - * <code>null</code> if no such annotation exists. - * @since 1.5 - */ - public <A extends Annotation> A getAnnotation(Class<A> annotationClass) - { - A foundAnnotation = null; - Annotation[] annotations = getAnnotations(); - for (Annotation annotation : annotations) - if (annotation.annotationType() == annotationClass) - foundAnnotation = (A) annotation; - return foundAnnotation; - } - - /** - * Returns all annotations associated with this class. If there are - * no annotations associated with this class, then a zero-length array - * will be returned. The returned array may be modified by the client - * code, but this will have no effect on the annotation content of this - * class, and hence no effect on the return value of this method for - * future callers. - * - * @return this class' annotations. - * @since 1.5 - */ - public Annotation[] getAnnotations() - { - HashMap<Class, Annotation> map = new HashMap<Class, Annotation>(); - for (Annotation a : getDeclaredAnnotations()) - map.put((Class) a.annotationType(), a); - for (Class<? super T> s = getSuperclass(); - s != null; - s = s.getSuperclass()) - { - for (Annotation a : s.getDeclaredAnnotations()) - { - Class k = (Class) a.annotationType(); - if (! map.containsKey(k) && k.isAnnotationPresent(Inherited.class)) - map.put(k, a); - } - } - Collection<Annotation> v = map.values(); - return v.toArray(new Annotation[v.size()]); - } - - /** - * <p> - * Returns the canonical name of this class, as defined by section - * 6.7 of the Java language specification. Each package, top-level class, - * top-level interface and primitive type has a canonical name. A member - * class has a canonical name, if its parent class has one. Likewise, - * an array type has a canonical name, if its component type does. - * Local or anonymous classes do not have canonical names. - * </p> - * <p> - * The canonical name for top-level classes, top-level interfaces and - * primitive types is always the same as the fully-qualified name. - * For array types, the canonical name is the canonical name of its - * component type with `[]' appended. - * </p> - * <p> - * The canonical name of a member class always refers to the place where - * the class was defined, and is composed of the canonical name of the - * defining class and the simple name of the member class, joined by `.'. - * For example, if a <code>Person</code> class has an inner class, - * <code>M</code>, then both its fully-qualified name and canonical name - * is <code>Person.M</code>. A subclass, <code>Staff</code>, of - * <code>Person</code> refers to the same inner class by the fully-qualified - * name of <code>Staff.M</code>, but its canonical name is still - * <code>Person.M</code>. - * </p> - * <p> - * Where no canonical name is present, <code>null</code> is returned. - * </p> - * - * @return the canonical name of the class, or <code>null</code> if the - * class doesn't have a canonical name. - * @since 1.5 - */ - public String getCanonicalName() - { - if (isArray()) - { - String componentName = getComponentType().getCanonicalName(); - if (componentName != null) - return componentName + "[]"; - } - if (isMemberClass()) - { - String memberName = getDeclaringClass().getCanonicalName(); - if (memberName != null) - return memberName + "." + getSimpleName(); - } - if (isLocalClass() || isAnonymousClass()) - return null; - return getName(); - } - - /** - * Returns all annotations directly defined by this class. If there are - * no annotations associated with this class, then a zero-length array - * will be returned. The returned array may be modified by the client - * code, but this will have no effect on the annotation content of this - * class, and hence no effect on the return value of this method for - * future callers. - * - * @return the annotations directly defined by this class. - * @since 1.5 - */ - public Annotation[] getDeclaredAnnotations() - { - Annotation[] result = getDeclaredAnnotationsInternal(); - if (result == null) - result = new Annotation[0]; - return result; - } - - private native Annotation[] getDeclaredAnnotationsInternal(); - - /** - * Returns true if an annotation for the specified type is associated - * with this class. This is primarily a short-hand for using marker - * annotations. - * - * @param annotationClass the type of annotation to look for. - * @return true if an annotation exists for the specified type. - * @since 1.5 - */ - public boolean isAnnotationPresent(Class<? extends Annotation> - annotationClass) - { - return getAnnotation(annotationClass) != null; - } - - /** - * Returns true if this object represents an anonymous class. - * - * @return true if this object represents an anonymous class. - * @since 1.5 - */ - public native boolean isAnonymousClass(); - - /** - * Returns true if this object represents an local class. - * - * @return true if this object represents an local class. - * @since 1.5 - */ - public native boolean isLocalClass(); - - /** - * Returns true if this object represents an member class. - * - * @return true if this object represents an member class. - * @since 1.5 - */ - public native boolean isMemberClass(); - - /** - * Utility method for use by classes in this package. - */ - static void setAccessible(final AccessibleObject obj) - { - AccessController.doPrivileged(new PrivilegedAction() - { - public Object run() - { - obj.setAccessible(true); - return null; - } - }); - } -} |