From d3cc3f10dac7b93c7b62d7e30b15f171fec3e8a5 Mon Sep 17 00:00:00 2001
From: Anthony Green <green@redhat.com>
Date: Mon, 30 Sep 2002 05:19:09 +0000
Subject: Add Proxy support.
From-SVN: r57635
---
libjava/java/lang/VMClassLoader.java | 8 +-
libjava/java/lang/natClassLoader.cc | 11 +
libjava/java/lang/reflect/InvocationHandler.java | 136 ++
libjava/java/lang/reflect/Proxy.java | 1586 ++++++++++++++++++++
.../lang/reflect/UndeclaredThrowableException.java | 128 ++
libjava/java/lang/reflect/natProxy.cc | 38 +
6 files changed, 1903 insertions(+), 4 deletions(-)
create mode 100644 libjava/java/lang/reflect/InvocationHandler.java
create mode 100644 libjava/java/lang/reflect/Proxy.java
create mode 100644 libjava/java/lang/reflect/UndeclaredThrowableException.java
create mode 100644 libjava/java/lang/reflect/natProxy.cc
(limited to 'libjava/java/lang')
diff --git a/libjava/java/lang/VMClassLoader.java b/libjava/java/lang/VMClassLoader.java
index 445272b..11b7554 100644
--- a/libjava/java/lang/VMClassLoader.java
+++ b/libjava/java/lang/VMClassLoader.java
@@ -43,10 +43,10 @@ class VMClassLoader {
* @return the class that was defined.
* @exception ClassFormatError if the byte array is not in proper classfile format.
*/
- // Not yet needed for libgcj.
-// final static native Class defineClass(ClassLoader cl, String name,
-// byte[] data, int offset, int len) throws ClassFormatError;
-
+ final static native Class defineClass(ClassLoader cl, String name,
+ byte[] data, int offset, int len)
+ throws ClassFormatError;
+
/**
* Helper to resolve all references to other classes from this class.
* @param c the class to resolve.
diff --git a/libjava/java/lang/natClassLoader.cc b/libjava/java/lang/natClassLoader.cc
index d33614d..c229943 100644
--- a/libjava/java/lang/natClassLoader.cc
+++ b/libjava/java/lang/natClassLoader.cc
@@ -171,6 +171,16 @@ java::lang::ClassLoader::markClassErrorState0 (java::lang::Class *klass)
}
jclass
+java::lang::VMClassLoader::defineClass (java::lang::ClassLoader *cl,
+ jstring name,
+ jbyteArray data,
+ jint offset,
+ jint length)
+{
+ return cl->defineClass (name, data, offset, length);
+}
+
+jclass
java::lang::VMClassLoader::getPrimitiveClass (jchar type)
{
char sig[2];
@@ -269,6 +279,7 @@ _Jv_PrepareCompiledClass (jclass klass)
else if (pool->tags[index] == JV_CONSTANT_String)
{
jstring str;
+
str = _Jv_NewStringUtf8Const (pool->data[index].utf8);
pool->data[index].o = str;
pool->tags[index] |= JV_CONSTANT_ResolvedFlag;
diff --git a/libjava/java/lang/reflect/InvocationHandler.java b/libjava/java/lang/reflect/InvocationHandler.java
new file mode 100644
index 0000000..91907e2
--- /dev/null
+++ b/libjava/java/lang/reflect/InvocationHandler.java
@@ -0,0 +1,136 @@
+/* java.lang.reflect.InvocationHandler - dynamically executes methods in
+ proxy instances
+ Copyright (C) 2001 Free Software Foundation, Inc.
+
+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., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 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.reflect;
+
+/**
+ * This interface defines an invocation handler. Suppose you are using
+ * reflection, and found a method that requires that its parameter
+ * be an object of a given interface. You want to call this method,
+ * but have no idea what classes implement that interface. So, you can
+ * create a {@link Proxy} instance, a convenient way to dynamically
+ * generate a class that meets all the necessary properties of that
+ * interface. But in order for the proxy instance to do any good, it
+ * needs to know what to do when interface methods are invoked! So,
+ * this interface is basically a cool wrapper that provides runtime
+ * code generation needed by proxy instances.<p>
+ *
+ * While this interface was designed for use by Proxy, it will also
+ * work on any object in general.<p>
+ *
+ * Hints for implementing this class:<br>
+ * <ul>
+ * <li>Don't forget that Object.equals, Object.hashCode, and
+ * Object.toString will call this handler. In particular,
+ * a naive call to proxy.equals, proxy.hashCode, or proxy.toString
+ * will put you in an infinite loop. And remember that string
+ * concatenation also invokes toString.</li>
+ * <li>Obey the contract of the Method object you are handling, or
+ * the proxy instance will be forced to throw a
+ * {@link NullPointerException}, {@link ClassCastException},
+ * or {@link UndeclaredThrowableException}.</li>
+ * <li>Be prepared to wrap/unwrap primitives as necessary.</li>
+ * <li>The Method object may be owned by a different interface than
+ * what was actually used as the qualifying type of the method
+ * invocation in the Java source code. This means that it might
+ * not always be safe to throw an exception listed as belonging
+ * to the method's throws clause.</li>
+ * </ul>
+ *
+ * <p><small>For a fun time, create an InvocationHandler that handles the
+ * methods of a proxy instance of the InvocationHandler interface!</small>
+ *
+ * @see Proxy
+ * @see UndeclaredThrowableException
+ *
+ * @author Eric Blake <ebb9@email.byu.edu>
+ * @since 1.3
+ * @status updated to 1.4
+ */
+public interface InvocationHandler
+{
+ /**
+ * When a method is invoked on a proxy instance, it is wrapped and
+ * this method is called instead, so that you may decide at runtime
+ * how the original method should behave.
+ *
+ * @param proxy the instance that the wrapped method should be
+ * invoked on. When this method is called by a Proxy object,
+ * `proxy' will be an instance of {@link Proxy}, and oddly enough,
+ * <code>Proxy.getInvocationHandler(proxy)</code> will return
+ * <code>this</code>!
+ * @param method the reflected method to invoke on the proxy.
+ * When this method is called by a Proxy object, 'method'
+ * will be the reflection object owned by the declaring
+ * class or interface, which may be a supertype of the
+ * interfaces the proxy directly implements.
+ * @param args the arguments passed to the original method, or
+ * <code>null</code> if the method takes no arguments.
+ * (But also be prepared to handle a 0-length array).
+ * Arguments of primitive type, such as <code>boolean</code>
+ * or <code>int</code>, are wrapped in the appropriate
+ * class such as {@link Boolean} or {@link Integer}.
+ * @return whatever is necessary to return from the wrapped method.
+ * If the wrapped method is <code>void</code>, the proxy
+ * instance will ignore it. If the wrapped method returns
+ * a primitive, this must be the correct wrapper type whose value
+ * is exactly assignable to the appropriate type (no widening
+ * will be performed); a null object in this case causes a
+ * {@link NullPointerException}. In all remaining cases, if
+ * the returned object is not assignment compatible to the
+ * declared type of the original method, the proxy instance
+ * will generate a {@link ClassCastException}.
+ * @throws Throwable this interface is listed as throwing anything,
+ * but the implementation should only throw unchecked
+ * exceptions and exceptions listed in the throws clause of
+ * all methods being overridden by the proxy instance. If
+ * something is thrown that is not compatible with the throws
+ * clause of all overridden methods, the proxy instance will
+ * wrap the exception in an UndeclaredThrowableException.
+ * Note that an exception listed in the throws clause of the
+ * `method' parameter might not be declared in additional
+ * interfaces also implemented by the proxy object.
+ *
+ * @see Proxy
+ * @see UndeclaredThrowableException
+ */
+ Object invoke(Object proxy, Method method, Object[] args)
+ throws Throwable;
+
+}
diff --git a/libjava/java/lang/reflect/Proxy.java b/libjava/java/lang/reflect/Proxy.java
new file mode 100644
index 0000000..972ac19
--- /dev/null
+++ b/libjava/java/lang/reflect/Proxy.java
@@ -0,0 +1,1586 @@
+/* Proxy.java -- build a proxy class that implements reflected interfaces
+ Copyright (C) 2001, 2002 Free Software Foundation, Inc.
+
+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., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 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.reflect;
+
+import java.io.Serializable;
+import java.security.ProtectionDomain;
+import java.util.Map;
+import java.util.HashMap;
+import java.util.Set;
+import java.util.HashSet;
+import java.util.Iterator;
+import gnu.classpath.Configuration;
+import gnu.java.lang.reflect.TypeSignature;
+
+/**
+ * This class allows you to dynamically create an instance of any (or
+ * even multiple) interfaces by reflection, and decide at runtime
+ * how that instance will behave by giving it an appropriate
+ * {@link InvocationHandler}. Proxy classes serialize specially, so
+ * that the proxy object can be reused between VMs, without requiring
+ * a persistent copy of the generated class code.
+ *
+ * <h3>Creation</h3>
+ * To create a proxy for some interface Foo:
+ *
+ * <pre>
+ * InvocationHandler handler = new MyInvocationHandler(...);
+ * Class proxyClass = Proxy.getProxyClass(
+ * Foo.class.getClassLoader(), new Class[] { Foo.class });
+ * Foo f = (Foo) proxyClass
+ * .getConstructor(new Class[] { InvocationHandler.class })
+ * .newInstance(new Object[] { handler });
+ * </pre>
+ * or more simply:
+ * <pre>
+ * Foo f = (Foo) Proxy.newProxyInstance(Foo.class.getClassLoader(),
+ * new Class[] { Foo.class },
+ * handler);
+ * </pre>
+ *
+ * <h3>Dynamic Proxy Classes</h3>
+ * A dynamic proxy class is created at runtime, and has the following
+ * properties:
+ * <ul>
+ * <li>The class is <code>public</code> and <code>final</code>,
+ * and is neither <code>abstract</code> nor an inner class.</li>
+ * <li>The class has no canonical name (there is no formula you can use
+ * to determine or generate its name), but begins with the
+ * sequence "$Proxy". Abuse this knowledge at your own peril.
+ * (For now, '$' in user identifiers is legal, but it may not
+ * be that way forever. You weren't using '$' in your
+ * identifiers, were you?)</li>
+ * <li>The class extends Proxy, and explicitly implements all the
+ * interfaces specified at creation, in order (this is important
+ * for determining how method invocation is resolved). Note that
+ * a proxy class implements {@link Serializable}, at least
+ * implicitly, since Proxy does, but true serial behavior
+ * depends on using a serializable invocation handler as well.</li>
+ * <li>If at least one interface is non-public, the proxy class
+ * will be in the same package. Otherwise, the package is
+ * unspecified. This will work even if the package is sealed
+ * from user-generated classes, because Proxy classes are
+ * generated by a trusted source. Meanwhile, the proxy class
+ * belongs to the classloader you designated.</li>
+ * <li>Reflection works as expected: {@link Class#getInterfaces()} and
+ * {@link Class#getMethods()} work as they do on normal classes.</li>
+ * <li>The method {@link #isProxyClass()} will distinguish between
+ * true proxy classes and user extensions of this class. It only
+ * returns true for classes created by {@link #getProxyClass}.</li>
+ * <li>The {@link ProtectionDomain} of a proxy class is the same as for
+ * bootstrap classes, such as Object or Proxy, since it is created by
+ * a trusted source. This protection domain will typically be granted
+ * {@link java.security.AllPermission}. But this is not a security
+ * risk, since there are adequate permissions on reflection, which is
+ * the only way to create an instance of the proxy class.</li>
+ * <li>The proxy class contains a single constructor, which takes as
+ * its only argument an {@link InvocationHandler}. The method
+ * {@link #newInstance} is shorthand to do the necessary
+ * reflection.</li>
+ * </ul>
+ *
+ * <h3>Proxy Instances</h3>
+ * A proxy instance is an instance of a proxy class. It has the
+ * following properties, many of which follow from the properties of a
+ * proxy class listed above:
+ * <ul>
+ * <li>For a proxy class with Foo listed as one of its interfaces, the
+ * expression <code>proxy instanceof Foo</code> will return true,
+ * and the expression <code>(Foo) proxy</code> will succeed without
+ * a {@link ClassCastException}.</li>
+ * <li>Each proxy instance has an invocation handler, which can be
+ * accessed by {@link #getInvocationHandler(Object)}. Any call
+ * to an interface method, including {@link Object#hashcode()},
+ * {@link Object#equals(Object)}, or {@link Object#toString()},
+ * but excluding the public final methods of Object, will be
+ * encoded and passed to the {@link InvocationHandler#invoke}
+ * method of this handler.</li>
+ * </ul>
+ *
+ * <h3>Inheritance Issues</h3>
+ * A proxy class may inherit a method from more than one interface.
+ * The order in which interfaces are listed matters, because it determines
+ * which reflected {@link Method} object will be passed to the invocation
+ * handler. This means that the dynamically generated class cannot
+ * determine through which interface a method is being invoked.<p>
+ *
+ * In short, if a method is declared in Object (namely, hashCode,
+ * equals, or toString), then Object will be used; otherwise, the
+ * leftmost interface that inherits or declares a method will be used,
+ * even if it has a more permissive throws clause than what the proxy
+ * class is allowed. Thus, in the invocation handler, it is not always
+ * safe to assume that every class listed in the throws clause of the
+ * passed Method object can safely be thrown; fortunately, the Proxy
+ * instance is robust enough to wrap all illegal checked exceptions in
+ * {@link UndeclaredThrowableException}.
+ *
+ * @see InvocationHandler
+ * @see UndeclaredThrowableException
+ * @see Class
+ * @author Eric Blake <ebb9@email.byu.edu>
+ * @since 1.3
+ * @status updated to 1.4, except for the use of ProtectionDomain
+ */
+public class Proxy implements Serializable
+{
+ /**
+ * Compatible with JDK 1.3+.
+ */
+ private static final long serialVersionUID = -2222568056686623797L;
+
+ /**
+ * Map of ProxyType to proxy class.
+ *
+ * @XXX This prevents proxy classes from being garbage collected.
+ * java.util.WeakHashSet is not appropriate, because that collects the
+ * keys, but we are interested in collecting the elements.
+ */
+ private static final Map proxyClasses = new HashMap();
+
+ /**
+ * The invocation handler for this proxy instance. For Proxy, this
+ * field is unused, but it appears here in order to be serialized in all
+ * proxy classes.
+ *
+ * <em>NOTE</em>: This implementation is more secure for proxy classes
+ * than what Sun specifies. Sun does not require h to be immutable, but
+ * this means you could change h after the fact by reflection. However,
+ * by making h immutable, we may break non-proxy classes which extend
+ * Proxy.
+ * @serial invocation handler associated with this proxy instance
+ */
+ protected final InvocationHandler h;
+
+ /**
+ * Constructs a new Proxy from a subclass (usually a proxy class),
+ * with the specified invocation handler.
+ *
+ * <em>NOTE</em>: This throws a NullPointerException if you attempt
+ * to create a proxy instance with a null handler using reflection.
+ * This behavior is not yet specified by Sun; see Sun Bug 4487672.
+ *
+ * @param handler the invocation handler, may be null if the subclass
+ * is not a proxy class
+ * @throws NullPointerException if handler is null and this is a proxy
+ * instance
+ */
+ protected Proxy(InvocationHandler handler)
+ {
+ if (handler == null && isProxyClass(getClass()))
+ throw new NullPointerException("invalid handler");
+ h = handler;
+ }
+
+ /**
+ * Returns the proxy {@link Class} for the given ClassLoader and array
+ * of interfaces, dynamically generating it if necessary.
+ *
+ * There are several restrictions on this method, the violation of
+ * which will result in an IllegalArgumentException or
+ * NullPointerException:
+ * <ul>
+ * <li>All objects in `interfaces' must represent distinct interfaces.
+ * Classes, primitive types, null, and duplicates are forbidden.</li>
+ * <li>The interfaces must be visible in the specified ClassLoader.
+ * In other words, for each interface i:
+ * <code>Class.forName(i.getName(), false, loader) == i</code>
+ * must be true.</li>
+ * <li>All non-public interfaces (if any) must reside in the same
+ * package, or the proxy class would be non-instantiable. If
+ * there are no non-public interfaces, the package of the proxy
+ * class is unspecified.</li>
+ * <li>All interfaces must be compatible - if two declare a method
+ * with the same name and parameters, the return type must be
+ * the same and the throws clause of the proxy class will be
+ * the maximal subset of subclasses of the throws clauses for
+ * each method that is overridden.</li>
+ * <li>VM constraints limit the number of interfaces a proxy class
+ * may directly implement (however, the indirect inheritance
+ * of {@link Serializable} does not count against this limit).
+ * Even though most VMs can theoretically have 65535
+ * superinterfaces for a class, the actual limit is smaller
+ * because a class's constant pool is limited to 65535 entries,
+ * and not all entries can be interfaces.</li>
+ * </ul><p>
+ *
+ * Note that different orders of interfaces produce distinct classes.
+ *
+ * @param loader the class loader to define the proxy class in; null
+ * implies the bootstrap class loader
+ * @param interfaces the array of interfaces the proxy class implements,
+ * may be empty, but not null
+ * @return the Class object of the proxy class
+ * @throws IllegalArgumentException if the constraints above were
+ * violated, except for problems with null
+ * @throws NullPointerException if `interfaces' is null or contains
+ * a null entry
+ */
+ // synchronized so that we aren't trying to build the same class
+ // simultaneously in two threads
+ public static synchronized Class getProxyClass(ClassLoader loader,
+ Class[] interfaces)
+ {
+ interfaces = (Class[]) interfaces.clone();
+ ProxyType pt = new ProxyType(loader, interfaces);
+ Class clazz = (Class) proxyClasses.get(pt);
+ if (clazz == null)
+ {
+ if (Configuration.HAVE_NATIVE_GET_PROXY_CLASS)
+ clazz = getProxyClass0(loader, interfaces);
+ else
+ {
+ ProxyData data = (Configuration.HAVE_NATIVE_GET_PROXY_DATA
+ ? getProxyData0(loader, interfaces)
+ : ProxyData.getProxyData(pt));
+
+ // FIXME workaround for bug in gcj 3.0.x
+ // Not needed with the latest gcj from cvs
+ //clazz = (Configuration.HAVE_NATIVE_GENERATE_PROXY_CLASS
+ // ? generateProxyClass0(loader, data)
+ // : new ClassFactory(data).generate(loader));
+ if (Configuration.HAVE_NATIVE_GENERATE_PROXY_CLASS)
+ clazz = generateProxyClass0(loader, data);
+ else
+ {
+ ClassFactory cf = new ClassFactory(data);
+ clazz = cf.generate(loader);
+ }
+ }
+
+ Object check = proxyClasses.put(pt, clazz);
+ // assert check == null && clazz != null;
+ if (check != null || clazz == null)
+ throw new InternalError(/*"Fatal flaw in getProxyClass"*/);
+ }
+ return clazz;
+ }
+
+ /**
+ * Combines several methods into one. This is equivalent to:
+ * <pre>
+ * Proxy.getProxyClass(loader, interfaces)
+ * .getConstructor(new Class[] {InvocationHandler.class})
+ * .newInstance(new Object[] {handler});
+ * </pre>
+ * except that it will not fail with the normal problems caused
+ * by reflection. It can still fail for the same reasons documented
+ * in getProxyClass, or if handler is null.
+ *
+ * @param loader the class loader to define the proxy class in; null
+ * implies the bootstrap class loader
+ * @param interfaces the array of interfaces the proxy class implements,
+ * may be empty, but not null
+ * @param handler the invocation handler, may not be null
+ * @return a proxy instance implementing the specified interfaces
+ * @throws IllegalArgumentException if the constraints for getProxyClass
+ * were violated, except for problems with null
+ * @throws NullPointerException if `interfaces' is null or contains
+ * a null entry, or if handler is null
+ * @see #getProxyClass(ClassLoader, Class[])
+ * @see Class#getConstructor(Class[])
+ * @see Constructor#newInstance(Object[])
+ */
+ public static Object newProxyInstance(ClassLoader loader,
+ Class[] interfaces,
+ InvocationHandler handler)
+ {
+ try
+ {
+ // getProxyClass() and Proxy() throw the necessary exceptions
+ return getProxyClass(loader, interfaces)
+ .getConstructor(new Class[] {InvocationHandler.class})
+ .newInstance(new Object[] {handler});
+ }
+ catch (RuntimeException e)
+ {
+ // Let IllegalArgumentException, NullPointerException escape.
+ // assert e instanceof IllegalArgumentException
+ // || e instanceof NullPointerException;
+ throw e;
+ }
+ catch (InvocationTargetException e)
+ {
+ // Let wrapped NullPointerException escape.
+ // assert e.getTargetException() instanceof NullPointerException
+ throw (NullPointerException) e.getCause();
+ }
+ catch (Exception e)
+ {
+ // Covers InstantiationException, IllegalAccessException,
+ // NoSuchMethodException, none of which should be generated
+ // if the proxy class was generated correctly.
+ // assert false;
+ throw (Error) new InternalError("Unexpected: " + e).initCause(e);
+ }
+ }
+
+ /**
+ * Returns true if and only if the Class object is a dynamically created
+ * proxy class (created by <code>getProxyClass</code> or by the
+ * syntactic sugar of <code>newProxyInstance</code>).
+ *
+ * <p>This check is secure (in other words, it is not simply
+ * <code>clazz.getSuperclass() == Proxy.class</code>), it will not
+ * be spoofed by non-proxy classes that extend Proxy.
+ *
+ * @param clazz the class to check, must not be null
+ * @return true if the class represents a proxy class
+ * @throws NullPointerException if clazz is null
+ */
+ // This is synchronized on the off chance that another thread is
+ // trying to add a class to the map at the same time we read it.
+ public static synchronized boolean isProxyClass(Class clazz)
+ {
+ if (! Proxy.class.isAssignableFrom(clazz))
+ return false;
+ // This is a linear search, even though we could do an O(1) search
+ // using new ProxyType(clazz.getClassLoader(), clazz.getInterfaces()).
+ return proxyClasses.containsValue(clazz);
+ }
+
+ /**
+ * Returns the invocation handler for the given proxy instance.<p>
+ *
+ * <em>NOTE</em>: We guarantee a non-null result if successful,
+ * but Sun allows the creation of a proxy instance with a null
+ * handler. See the comments for {@link #Proxy(InvocationHandler)}.
+ *
+ * @param proxy the proxy instance, must not be null
+ * @return the invocation handler, guaranteed non-null.
+ * @throws IllegalArgumentException if
+ * <code>Proxy.isProxyClass(proxy.getClass())</code> returns false.
+ * @throws NullPointerException if proxy is null
+ */
+ public static InvocationHandler getInvocationHandler(Object proxy)
+ {
+ if (! isProxyClass(proxy.getClass()))
+ throw new IllegalArgumentException("not a proxy instance");
+ return ((Proxy) proxy).h;
+ }
+
+ /**
+ * Optional native method to replace (and speed up) the pure Java
+ * implementation of getProxyClass. Only needed if
+ * Configuration.HAVE_NATIVE_GET_PROXY_CLASS is true, this does the
+ * work of both getProxyData0 and generateProxyClass0 with no
+ * intermediate form in Java. The native code may safely assume that
+ * this class must be created, and does not already exist.
+ *
+ * @param loader the class loader to define the proxy class in; null
+ * implies the bootstrap class loader
+ * @param interfaces the interfaces the class will extend
+ * @return the generated proxy class
+ * @throws IllegalArgumentException if the constraints for getProxyClass
+ * were violated, except for problems with null
+ * @throws NullPointerException if `interfaces' is null or contains
+ * a null entry, or if handler is null
+ * @see Configuration#HAVE_NATIVE_GET_PROXY_CLASS
+ * @see #getProxyClass(ClassLoader, Class[])
+ * @see #getProxyData0(ClassLoader, Class[])
+ * @see #generateProxyClass0(ProxyData)
+ */
+ private static native Class getProxyClass0(ClassLoader loader,
+ Class[] interfaces);
+
+ /**
+ * Optional native method to replace (and speed up) the pure Java
+ * implementation of getProxyData. Only needed if
+ * Configuration.HAVE_NATIVE_GET_PROXY_DATA is true. The native code
+ * may safely assume that a new ProxyData object must be created which
+ * does not duplicate any existing ones.
+ *
+ * @param loader the class loader to define the proxy class in; null
+ * implies the bootstrap class loader
+ * @param interfaces the interfaces the class will extend
+ * @return all data that is required to make this proxy class
+ * @throws IllegalArgumentException if the constraints for getProxyClass
+ * were violated, except for problems with null
+ * @throws NullPointerException if `interfaces' is null or contains
+ * a null entry, or if handler is null
+ * @see Configuration.HAVE_NATIVE_GET_PROXY_DATA
+ * @see #getProxyClass(ClassLoader, Class[])
+ * @see #getProxyClass0(ClassLoader, Class[])
+ * @see ProxyType#getProxyData()
+ */
+ private static native ProxyData getProxyData0(ClassLoader loader,
+ Class[] interfaces);
+
+ /**
+ * Optional native method to replace (and speed up) the pure Java
+ * implementation of generateProxyClass. Only needed if
+ * Configuration.HAVE_NATIVE_GENERATE_PROXY_CLASS is true. The native
+ * code may safely assume that a new Class must be created, and that
+ * the ProxyData object does not describe any existing class.
+ *
+ * @param loader the class loader to define the proxy class in; null
+ * implies the bootstrap class loader
+ * @param data the struct of information to convert to a Class. This
+ * has already been verified for all problems except exceeding
+ * VM limitations
+ * @return the newly generated class
+ * @throws IllegalArgumentException if VM limitations are exceeded
+ * @see #getProxyClass(ClassLoader, Class[])
+ * @see #getProxyClass0(ClassLoader, Class[])
+ * @see ProxyData#generateProxyClass(ClassLoader)
+ */
+ private static native Class generateProxyClass0(ClassLoader loader,
+ ProxyData data);
+
+
+ /**
+ * Helper class for mapping unique ClassLoader and interface combinations
+ * to proxy classes.
+ *
+ * @author Eric Blake <ebb9@email.byu.edu>
+ */
+ private static final class ProxyType
+ {
+ /**
+ * Store the class loader (may be null)
+ */
+ final ClassLoader loader;
+
+ /**
+ * Store the interfaces (never null, all elements are interfaces)
+ */
+ final Class[] interfaces;
+
+ /**
+ * Construct the helper object.
+ *
+ * @param loader the class loader to define the proxy class in; null
+ * implies the bootstrap class loader
+ * @param interfaces an array of interfaces
+ */
+ ProxyType(ClassLoader loader, Class[] interfaces)
+ {
+ this.loader = loader;
+ this.interfaces = interfaces;
+ }
+
+ /**
+ * Calculates the hash code.
+ *
+ * @return a combination of the classloader and interfaces hashcodes.
+ */
+ public int hashCode()
+ {
+ int hash = (loader == null) ? 0 : loader.hashCode();
+ for (int i = 0; i < interfaces.length; i++)
+ hash = hash * 31 + interfaces[i].hashCode();
+ return hash;
+ }
+
+ /**
+ * Calculates equality.
+ *
+ * @param the object to compare to
+ * @return true if it is a ProxyType with same data
+ */
+ public boolean equals(Object other)
+ {
+ ProxyType pt = (ProxyType) other;
+ if (loader != pt.loader || interfaces.length != pt.interfaces.length)
+ return false;
+ int i = interfaces.length;
+ while (--i >= 0)
+ if (interfaces[i] != pt.interfaces[i])
+ return false;
+ return true;
+ }
+ } // class ProxyType
+
+
+ /**
+ * Helper class which allows hashing of a method name and signature
+ * without worrying about return type, declaring class, or throws clause,
+ * and which reduces the maximally common throws clause between two methods
+ *
+ * @author Eric Blake <ebb9@email.byu.edu>
+ */
+ private static final class ProxySignature
+ {
+ /**
+ * The core signatures which all Proxy instances handle.
+ */
+ static final HashMap coreMethods = new HashMap();
+ static
+ {
+ try
+ {
+ ProxySignature sig
+ = new ProxySignature(Object.class
+ .getMethod("equals",
+ new Class[] {Object.class}));
+ coreMethods.put(sig, sig);
+ sig = new ProxySignature(Object.class.getMethod("hashCode", null));
+ coreMethods.put(sig, sig);
+ sig = new ProxySignature(Object.class.getMethod("toString", null));
+ coreMethods.put(sig, sig);
+ }
+ catch (Exception e)
+ {
+ // assert false;
+ throw (Error) new InternalError("Unexpected: " + e).initCause(e);
+ }
+ }
+
+ /**
+ * The underlying Method object, never null
+ */
+ final Method method;
+
+ /**
+ * The set of compatible thrown exceptions, may be empty
+ */
+ final Set exceptions = new HashSet();
+
+ /**
+ * Construct a signature
+ *
+ * @param method the Method this signature is based on, never null
+ */
+ ProxySignature(Method method)
+ {
+ this.method = method;
+ Class[] exc = method.getExceptionTypes();
+ int i = exc.length;
+ while (--i >= 0)
+ {
+ // discard unchecked exceptions
+ if (Error.class.isAssignableFrom(exc[i])
+ || RuntimeException.class.isAssignableFrom(exc[i]))
+ continue;
+ exceptions.add(exc[i]);
+ }
+ }
+
+ /**
+ * Given a method, make sure it's return type is identical
+ * to this, and adjust this signature's throws clause appropriately
+ *
+ * @param other the signature to merge in
+ * @throws IllegalArgumentException if the return types conflict
+ */
+ void checkCompatibility(ProxySignature other)
+ {
+ if (method.getReturnType() != other.method.getReturnType())
+ throw new IllegalArgumentException("incompatible return types: "
+ + method + ", " + other.method);
+
+ // if you can think of a more efficient way than this O(n^2) search,
+ // implement it!
+ int size1 = exceptions.size();
+ int size2 = other.exceptions.size();
+ boolean[] valid1 = new boolean[size1];
+ boolean[] valid2 = new boolean[size2];
+ Iterator itr = exceptions.iterator();
+ int pos = size1;
+ while (--pos >= 0)
+ {
+ Class c1 = (Class) itr.next();
+ Iterator itr2 = other.exceptions.iterator();
+ int pos2 = size2;
+ while (--pos2 >= 0)
+ {
+ Class c2 = (Class) itr2.next();
+ if (c2.isAssignableFrom(c1))
+ valid1[pos] = true;
+ if (c1.isAssignableFrom(c2))
+ valid2[pos2] = true;
+ }
+ }
+ pos = size1;
+ itr = exceptions.iterator();
+ while (--pos >= 0)
+ {
+ itr.next();
+ if (! valid1[pos])
+ itr.remove();
+ }
+ pos = size2;
+ itr = other.exceptions.iterator();
+ while (--pos >= 0)
+ {
+ itr.next();
+ if (! valid2[pos])
+ itr.remove();
+ }
+ exceptions.addAll(other.exceptions);
+ }
+
+ /**
+ * Calculates the hash code.
+ *
+ * @return a combination of name and parameter types
+ */
+ public int hashCode()
+ {
+ int hash = method.getName().hashCode();
+ Class[] types = method.getParameterTypes();
+ for (int i = 0; i < types.length; i++)
+ hash = hash * 31 + types[i].hashCode();
+ return hash;
+ }
+
+ /**
+ * Calculates equality.
+ *
+ * @param the object to compare to
+ * @return true if it is a ProxySignature with same data
+ */
+ public boolean equals(Object other)
+ {
+ ProxySignature ps = (ProxySignature) other;
+ Class[] types1 = method.getParameterTypes();
+ Class[] types2 = ps.method.getParameterTypes();
+ if (! method.getName().equals(ps.method.getName())
+ || types1.length != types2.length)
+ return false;
+ int i = types1.length;
+ while (--i >= 0)
+ if (types1[i] != types2[i])
+ return false;
+ return true;
+ }
+ } // class ProxySignature
+
+
+ /**
+ * A flat representation of all data needed to generate bytecode/instantiate
+ * a proxy class. This is basically a struct.
+ *
+ * @author Eric Blake <ebb9@email.byu.edu>
+ */
+ private static final class ProxyData
+ {
+ /**
+ * The package this class is in. Possibly null, meaning the unnamed
+ * package.
+ */
+ Package pack;
+
+ /**
+ * The interfaces this class implements. Non-null, but possibly empty.
+ */
+ Class[] interfaces;
+
+ /**
+ * The Method objects this class must pass as the second argument to
+ * invoke (also useful for determining what methods this class has).
+ * Non-null, non-empty (includes at least Object.hashCode, Object.equals,
+ * and Object.toString).
+ */
+ Method[] methods;
+
+ /**
+ * The exceptions that do not need to be wrapped in
+ * UndeclaredThrowableException. exceptions[i] is the same as, or a
+ * subset of subclasses, of methods[i].getExceptionTypes(), depending on
+ * compatible throws clauses with multiple inheritance. It is unspecified
+ * if these lists include or exclude subclasses of Error and
+ * RuntimeException, but excluding them is harmless and generates a
+ * smaller class.
+ */
+ Class[][] exceptions;
+
+ /**
+ * For unique id's
+ */
+ private static int count = 0;
+
+ /**
+ * The id of this proxy class
+ */
+ final int id = count++;
+
+ /**
+ * Construct a ProxyData with uninitialized data members.
+ */
+ ProxyData()
+ {
+ }
+
+ /**
+ * Verifies that the arguments are legal, and sets up remaining data
+ * This should only be called when a class must be generated, as
+ * it is expensive.
+ *
+ * @param pt the ProxyType to convert to ProxyData
+ * @return the flattened, verified ProxyData structure for use in
+ * class generation
+ * @throws IllegalArgumentException if `interfaces' contains
+ * non-interfaces or incompatible combinations, and verify is true
+ * @throws NullPointerException if interfaces is null or contains null
+ */
+ static ProxyData getProxyData(ProxyType pt)
+ {
+ Map method_set = (Map) ProxySignature.coreMethods.clone();
+ boolean in_package = false; // true if we encounter non-public interface
+
+ ProxyData data = new ProxyData();
+ data.interfaces = pt.interfaces;
+
+ // if interfaces is too large, we croak later on when the constant
+ // pool overflows
+ int i = data.interfaces.length;
+ while (--i >= 0)
+ {
+ Class inter = data.interfaces[i];
+ if (! inter.isInterface())
+ throw new IllegalArgumentException("not an interface: " + inter);
+ try
+ {
+ if (Class.forName(inter.getName(), false, pt.loader) != inter)
+ throw new IllegalArgumentException("not accessible in "
+ + "classloader: " + inter);
+ }
+ catch (ClassNotFoundException e)
+ {
+ throw new IllegalArgumentException("not accessible in "
+ + "classloader: " + inter);
+ }
+ if (! Modifier.isPublic(inter.getModifiers()))
+ if (in_package)
+ {
+ Package p = inter.getPackage();
+ if (data.pack != inter.getPackage())
+ throw new IllegalArgumentException("non-public interfaces "
+ + "from different "
+ + "packages");
+ }
+ else
+ {
+ in_package = true;
+ data.pack = inter.getPackage();
+ }
+ for (int j = i-1; j >= 0; j--)
+ if (data.interfaces[j] == inter)
+ throw new IllegalArgumentException("duplicate interface: "
+ + inter);
+ Method[] methods = inter.getMethods();
+ int j = methods.length;
+ while (--j >= 0)
+ {
+ ProxySignature sig = new ProxySignature(methods[j]);
+ ProxySignature old = (ProxySignature) method_set.put(sig, sig);
+ if (old != null)
+ sig.checkCompatibility(old);
+ }
+ }
+
+ i = method_set.size();
+ data.methods = new Method[i];
+ data.exceptions = new Class[i][];
+ Iterator itr = method_set.values().iterator();
+ while (--i >= 0)
+ {
+ ProxySignature sig = (ProxySignature) itr.next();
+ data.methods[i] = sig.method;
+ data.exceptions[i] = (Class[]) sig.exceptions
+ .toArray(new Class[sig.exceptions.size()]);
+ }
+ return data;
+ }
+ } // class ProxyData
+
+
+ /**
+ * Does all the work of building a class. By making this a nested class,
+ * this code is not loaded in memory if the VM has a native
+ * implementation instead.
+ *
+ * @author Eric Blake <ebb9@email.byu.edu>
+ */
+ private static final class ClassFactory
+ {
+ /** Constants for assisting the compilation */
+ private static final byte POOL = 0;
+ private static final byte FIELD = 1;
+ private static final byte METHOD = 2;
+ private static final byte INTERFACE = 3;
+ private static final String CTOR_SIG
+ = "(Ljava/lang/reflect/InvocationHandler;)V";
+ private static final String INVOKE_SIG = "(Ljava/lang/Object;"
+ + "Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;";
+
+ /** Bytecodes for insertion in the class definition byte[] */
+ private static final char ACONST_NULL = 1;
+ private static final char ICONST_0 = 3;
+ private static final char BIPUSH = 16;
+ private static final char SIPUSH = 17;
+ private static final char ILOAD = 21;
+ private static final char ILOAD_0 = 26;
+ private static final char ALOAD_0 = 42;
+ private static final char ALOAD_1 = 43;
+ private static final char AALOAD = 50;
+ private static final char AASTORE = 83;
+ private static final char DUP = 89;
+ private static final char DUP_X1 = 90;
+ private static final char SWAP = 95;
+ private static final char IRETURN = 172;
+ private static final char LRETURN = 173;
+ private static final char FRETURN = 174;
+ private static final char DRETURN = 175;
+ private static final char ARETURN = 176;
+ private static final char RETURN = 177;
+ private static final char GETSTATIC = 178;
+ private static final char GETFIELD = 180;
+ private static final char INVOKEVIRTUAL = 182;
+ private static final char INVOKESPECIAL = 183;
+ private static final char INVOKESTATIC = 184;
+ private static final char INVOKEINTERFACE = 185;
+ private static final char NEW = 187;
+ private static final char ANEWARRAY = 189;
+ private static final char ATHROW = 191;
+ private static final char CHECKCAST = 192;
+
+ // Implementation note: we use StringBuffers to hold the byte data, since
+ // they automatically grow. However, we only use the low 8 bits of
+ // every char in the array, so we are using twice the necessary memory
+ // for the ease StringBuffer provides.
+
+ /** The constant pool. */
+ private final StringBuffer pool = new StringBuffer();
+ /** The rest of the class data. */
+ private final StringBuffer stream = new StringBuffer();
+
+ /** Map of strings to byte sequences, to minimize size of pool. */
+ private final Map poolEntries = new HashMap();
+
+ /** The VM name of this proxy class. */
+ private final String qualName;
+
+ /**
+ * The Method objects the proxy class refers to when calling the
+ * invocation handler.
+ */
+ private final Method[] methods;
+
+ /**
+ * Initializes the buffers with the bytecode contents for a proxy class.
+ *
+ * @param data the remainder of the class data
+ * @throws IllegalArgumentException if anything else goes wrong this
+ * late in the game; as far as I can tell, this will only happen
+ * if the constant pool overflows, which is possible even when
+ * the user doesn't exceed the 65535 interface limit
+ */
+ ClassFactory(ProxyData data)
+ {
+ methods = data.methods;
+
+ // magic = 0xcafebabe
+ // minor_version = 0
+ // major_version = 46
+ // constant_pool_count: place-holder for now
+ pool.append("\u00ca\u00fe\u00ba\u00be\0\0\0\56\0\0");
+ // constant_pool[], filled in as we go
+
+ // access_flags
+ putU2(Modifier.SUPER | Modifier.FINAL | Modifier.PUBLIC);
+ // this_class
+ qualName = ((data.pack == null ? "" : data.pack.getName() + '.')
+ + "$Proxy" + data.id);
+ putU2(classInfo(TypeSignature.getEncodingOfClass(qualName, false)));
+ // super_class
+ putU2(classInfo("java/lang/reflect/Proxy"));
+
+ // interfaces_count
+ putU2(data.interfaces.length);
+ // interfaces[]
+ for (int i = 0; i < data.interfaces.length; i++)
+ putU2(classInfo(data.interfaces[i]));
+
+ // Recall that Proxy classes serialize specially, so we do not need
+ // to worry about a <clinit> method for this field. Instead, we
+ // just assign it by reflection after the class is successfully loaded.
+ // fields_count - private static Method[] m;
+ putU2(1);
+ // fields[]
+ // m.access_flags
+ putU2(Modifier.PRIVATE | Modifier.STATIC);
+ // m.name_index
+ putU2(utf8Info("m"));
+ // m.descriptor_index
+ putU2(utf8Info("[Ljava/lang/reflect/Method;"));
+ // m.attributes_count
+ putU2(0);
+ // m.attributes[]
+
+ // methods_count - # handler methods, plus <init>
+ putU2(methods.length + 1);
+ // methods[]
+ // <init>.access_flags
+ putU2(Modifier.PUBLIC);
+ // <init>.name_index
+ putU2(utf8Info("<init>"));
+ // <init>.descriptor_index
+ putU2(utf8Info(CTOR_SIG));
+ // <init>.attributes_count - only Code is needed
+ putU2(1);
+ // <init>.Code.attribute_name_index
+ putU2(utf8Info("Code"));
+ // <init>.Code.attribute_length = 18
+ // <init>.Code.info:
+ // $Proxynn(InvocationHandler h) { super(h); }
+ // <init>.Code.max_stack = 2
+ // <init>.Code.max_locals = 2
+ // <init>.Code.code_length = 6
+ // <init>.Code.code[]
+ stream.append("\0\0\0\22\0\2\0\2\0\0\0\6" + ALOAD_0 + ALOAD_1
+ + INVOKESPECIAL);
+ putU2(refInfo(METHOD, "java/lang/reflect/Proxy", "<init>", CTOR_SIG));
+ // <init>.Code.exception_table_length = 0
+ // <init>.Code.exception_table[]
+ // <init>.Code.attributes_count = 0
+ // <init>.Code.attributes[]
+ stream.append(RETURN + "\0\0\0\0");
+
+ for (int i = methods.length - 1; i >= 0; i--)
+ emitMethod(i, data.exceptions[i]);
+
+ // attributes_count
+ putU2(0);
+ // attributes[] - empty; omit SourceFile attribute
+ // XXX should we mark this with a Synthetic attribute?
+ }
+
+ /**
+ * Produce the bytecode for a single method.
+ *
+ * @param i the index of the method we are building
+ * @param e the exceptions possible for the method
+ */
+ private void emitMethod(int i, Class[] e)
+ {
+ // First, we precalculate the method length and other information.
+
+ Method m = methods[i];
+ Class[] paramtypes = m.getParameterTypes();
+ int wrap_overhead = 0; // max words taken by wrapped primitive
+ int param_count = 1; // 1 for this
+ int code_length = 16; // aload_0, getfield, aload_0, getstatic, const,
+ // aaload, const/aconst_null, invokeinterface
+ if (i > 5)
+ {
+ if (i > Byte.MAX_VALUE)
+ code_length += 2; // sipush
+ else
+ code_length++; // bipush
+ }
+ if (paramtypes.length > 0)
+ {
+ code_length += 3; // anewarray
+ if (paramtypes.length > Byte.MAX_VALUE)
+ code_length += 2; // sipush
+ else if (paramtypes.length > 5)
+ code_length++; // bipush
+ for (int j = 0; j < paramtypes.length; j++)
+ {
+ code_length += 4; // dup, const, load, store
+ Class type = paramtypes[j];
+ if (j > 5)
+ {
+ if (j > Byte.MAX_VALUE)
+ code_length += 2; // sipush
+ else
+ code_length++; // bipush
+ }
+ if (param_count >= 4)
+ code_length++; // 2-byte load
+ param_count++;
+ if (type.isPrimitive())
+ {
+ code_length += 7; // new, dup, invokespecial
+ if (type == long.class || type == double.class)
+ {
+ wrap_overhead = 3;
+ param_count++;
+ }
+ else if (wrap_overhead < 2)
+ wrap_overhead = 2;
+ }
+ }
+ }
+ int end_pc = code_length;
+ Class ret_type = m.getReturnType();
+ if (ret_type == void.class)
+ code_length++; // return
+ else if (ret_type.isPrimitive())
+ code_length += 7; // cast, invokevirtual, return
+ else
+ code_length += 4; // cast, return
+ int exception_count = 0;
+ boolean throws_throwable = false;
+ for (int j = 0; j < e.length; j++)
+ if (e[j] == Throwable.class)
+ {
+ throws_throwable = true;
+ break;
+ }
+ if (! throws_throwable)
+ {
+ exception_count = e.length + 3; // Throwable, Error, RuntimeException
+ code_length += 9; // new, dup_x1, swap, invokespecial, athrow
+ }
+ int handler_pc = code_length - 1;
+ StringBuffer signature = new StringBuffer("(");
+ for (int j = 0; j < paramtypes.length; j++)
+ signature.append(TypeSignature.getEncodingOfClass(paramtypes[j]));
+ signature.append(")").append(TypeSignature.getEncodingOfClass(ret_type));
+
+ // Now we have enough information to emit the method.
+
+ // handler.access_flags
+ putU2(Modifier.PUBLIC | Modifier.FINAL);
+ // handler.name_index
+ putU2(utf8Info(m.getName()));
+ // handler.descriptor_index
+ putU2(utf8Info(signature.toString()));
+ // handler.attributes_count - Code is necessary, Exceptions possible
+ putU2(e.length > 0 ? 2 : 1);
+
+ // handler.Code.info:
+ // type name(args) {
+ // try {
+ // return (type) h.invoke(this, methods[i], new Object[] {args});
+ // } catch (<declared Exceptions> e) {
+ // throw e;
+ // } catch (Throwable t) {
+ // throw new UndeclaredThrowableException(t);
+ // }
+ // }
+ // Special cases:
+ // if arg_n is primitive, wrap it
+ // if method throws Throwable, try-catch is not needed
+ // if method returns void, return statement not needed
+ // if method returns primitive, unwrap it
+ // save space by sharing code for all the declared handlers
+
+ // handler.Code.attribute_name_index
+ putU2(utf8Info("Code"));
+ // handler.Code.attribute_length
+ putU4(12 + code_length + 8 * exception_count);
+ // handler.Code.max_stack
+ putU2(param_count == 1 ? 4 : 7 + wrap_overhead);
+ // handler.Code.max_locals
+ putU2(param_count);
+ // handler.Code.code_length
+ putU4(code_length);
+ // handler.Code.code[]
+ putU1(ALOAD_0);
+ putU1(GETFIELD);
+ putU2(refInfo(FIELD, "java/lang/reflect/Proxy", "h",
+ "Ljava/lang/reflect/InvocationHandler;"));
+ putU1(ALOAD_0);
+ putU1(GETSTATIC);
+ putU2(refInfo(FIELD, TypeSignature.getEncodingOfClass(qualName, false),
+ "m", "[Ljava/lang/reflect/Method;"));
+ putConst(i);
+ putU1(AALOAD);
+ if (paramtypes.length > 0)
+ {
+ putConst(paramtypes.length);
+ putU1(ANEWARRAY);
+ putU2(classInfo("java/lang/Object"));
+ param_count = 1;
+ for (int j = 0; j < paramtypes.length; j++, param_count++)
+ {
+ putU1(DUP);
+ putConst(j);
+ if (paramtypes[j].isPrimitive())
+ {
+ putU1(NEW);
+ putU2(classInfo(wrapper(paramtypes[j])));
+ putU1(DUP);
+ }
+ putLoad(param_count, paramtypes[j]);
+ if (paramtypes[j].isPrimitive())
+ {
+ putU1(INVOKESPECIAL);
+ putU2(refInfo(METHOD, wrapper(paramtypes[j]), "<init>",
+ '(' + (TypeSignature
+ .getEncodingOfClass(paramtypes[j])
+ + ")V")));
+ if (paramtypes[j] == long.class
+ || paramtypes[j] == double.class)
+ param_count++;
+ }
+ putU1(AASTORE);
+ }
+ }
+ else
+ putU1(ACONST_NULL);
+ putU1(INVOKEINTERFACE);
+ putU2(refInfo(INTERFACE, "java/lang/reflect/InvocationHandler",
+ "invoke", INVOKE_SIG));
+ putU1(4); // InvocationHandler, this, Method, Object[]
+ putU1(0);
+ if (ret_type == void.class)
+ putU1(RETURN);
+ else if (ret_type.isPrimitive())
+ {
+ putU1(CHECKCAST);
+ putU2(classInfo(wrapper(ret_type)));
+ putU1(INVOKEVIRTUAL);
+ putU2(refInfo(METHOD, wrapper(ret_type),
+ ret_type.getName() + "Value",
+ "()" + TypeSignature.getEncodingOfClass(ret_type)));
+ if (ret_type == long.class)
+ putU1(LRETURN);
+ else if (ret_type == float.class)
+ putU1(FRETURN);
+ else if (ret_type == double.class)
+ putU1(DRETURN);
+ else
+ putU1(IRETURN);
+ }
+ else
+ {
+ putU1(CHECKCAST);
+ putU2(classInfo(ret_type));
+ putU1(ARETURN);
+ }
+ if (! throws_throwable)
+ {
+ putU1(NEW);
+ putU2(classInfo("java/lang/reflect/UndeclaredThrowableException"));
+ putU1(DUP_X1);
+ putU1(SWAP);
+ putU1(INVOKESPECIAL);
+ putU2(refInfo(METHOD,
+ "java/lang/reflect/UndeclaredThrowableException",
+ "<init>", "(Ljava/lang/Throwable;)V"));
+ putU1(ATHROW);
+ }
+
+ // handler.Code.exception_table_length
+ putU2(exception_count);
+ // handler.Code.exception_table[]
+ if (! throws_throwable)
+ {
+ // handler.Code.exception_table.start_pc
+ putU2(0);
+ // handler.Code.exception_table.end_pc
+ putU2(end_pc);
+ // handler.Code.exception_table.handler_pc
+ putU2(handler_pc);
+ // handler.Code.exception_table.catch_type
+ putU2(classInfo("java/lang/Error"));
+ // handler.Code.exception_table.start_pc
+ putU2(0);
+ // handler.Code.exception_table.end_pc
+ putU2(end_pc);
+ // handler.Code.exception_table.handler_pc
+ putU2(handler_pc);
+ // handler.Code.exception_table.catch_type
+ putU2(classInfo("java/lang/RuntimeException"));
+ for (int j = 0; j < e.length; j++)
+ {
+ // handler.Code.exception_table.start_pc
+ putU2(0);
+ // handler.Code.exception_table.end_pc
+ putU2(end_pc);
+ // handler.Code.exception_table.handler_pc
+ putU2(handler_pc);
+ // handler.Code.exception_table.catch_type
+ putU2(classInfo(e[j]));
+ }
+ // handler.Code.exception_table.start_pc
+ putU2(0);
+ // handler.Code.exception_table.end_pc
+ putU2(end_pc);
+ // handler.Code.exception_table.handler_pc -
+ // -8 for undeclared handler, which falls thru to normal one
+ putU2(handler_pc - 8);
+ // handler.Code.exception_table.catch_type
+ putU2(0);
+ }
+ // handler.Code.attributes_count
+ putU2(0);
+ // handler.Code.attributes[]
+
+ if (e.length > 0)
+ {
+ // handler.Exceptions.attribute_name_index
+ putU2(utf8Info("Exceptions"));
+ // handler.Exceptions.attribute_length
+ putU4(2 * e.length + 2);
+ // handler.Exceptions.number_of_exceptions
+ putU2(e.length);
+ // handler.Exceptions.exception_index_table[]
+ for (int j = 0; j < e.length; j++)
+ putU2(classInfo(e[j]));
+ }
+ }
+
+ /**
+ * Creates the Class object that corresponds to the bytecode buffers
+ * built when this object was constructed.
+ *
+ * @param loader the class loader to define the proxy class in; null
+ * implies the bootstrap class loader
+ * @return the proxy class Class object
+ */
+ final Class generate(ClassLoader loader)
+ {
+ byte[] bytecode = new byte[pool.length() + stream.length()];
+ // More efficient to bypass calling charAt() repetitively.
+ char[] c = pool.toString().toCharArray();
+ int i = c.length;
+ while (--i >= 0)
+ bytecode[i] = (byte) c[i];
+ c = stream.toString().toCharArray();
+ i = c.length;
+ int j = bytecode.length;
+ while (i > 0)
+ bytecode[--j] = (byte) c[--i];
+
+ // Patch the constant pool size, which we left at 0 earlier.
+ int count = poolEntries.size() + 1;
+ bytecode[8] = (byte) (count >> 8);
+ bytecode[9] = (byte) count;
+
+ try
+ {
+ // XXX Do we require more native support here?
+
+ // XXX Security hole - it is possible for another thread to grab the
+ // VMClassLoader.defineClass Method object, and abuse it while we
+ // have temporarily made it accessible. Do we need to add some
+ // synchronization lock to prevent user reflection while we use it?
+
+ // XXX This is waiting on VM support for protection domains.
+
+ Class vmClassLoader = Class.forName("java.lang.VMClassLoader");
+ Class[] types = {ClassLoader.class, String.class,
+ byte[].class, int.class, int.class,
+ /* ProtectionDomain.class */ };
+ Method m = vmClassLoader.getDeclaredMethod("defineClass", types);
+
+ // Bypass the security check of setAccessible(true), since this
+ // is trusted code. But note the comment above about the security
+ // risk of doing this outside a synchronized block.
+ m.flag = true;
+ Object[] args = {loader, qualName, bytecode, new Integer(0),
+ new Integer(bytecode.length),
+ /* Object.class.getProtectionDomain() */ };
+ Class clazz = (Class) m.invoke(null, args);
+ m.flag = false;
+
+ // Finally, initialize the m field of the proxy class, before
+ // returning it.
+
+ // No security risk here, since clazz has not been exposed yet,
+ // so user code cannot grab the same reflection object.
+ Field f = clazz.getDeclaredField("m");
+ f.flag = true;
+ // we can share the array, because it is not publicized
+ f.set(null, methods);
+ f.flag = false;
+
+ return clazz;
+ }
+ catch (Throwable e)
+ {
+ // assert false;
+ throw (Error) new InternalError("Unexpected: " + e).initCause(e);
+ }
+ }
+
+ /**
+ * Put a single byte on the stream.
+ *
+ * @param i the information to add (only lowest 8 bits are used)
+ */
+ private void putU1(int i)
+ {
+ stream.append((char) i);
+ }
+
+ /**
+ * Put two bytes on the stream.
+ *
+ * @param i the information to add (only lowest 16 bits are used)
+ */
+ private void putU2(int i)
+ {
+ stream.append((char) (i >> 8)).append((char) i);
+ }
+
+ /**
+ * Put four bytes on the stream.
+ *
+ * @param i the information to add (treated as unsigned)
+ */
+ private void putU4(int i)
+ {
+ stream.append((char) (i >> 24)).append((char) (i >> 16));
+ stream.append((char) (i >> 8)).append((char) i);
+ }
+
+ /**
+ * Put bytecode to load a constant integer on the stream. This only
+ * needs to work for values less than Short.MAX_VALUE.
+ *
+ * @param i the int to add
+ */
+ private void putConst(int i)
+ {
+ if (i >= -1 && i <= 5)
+ putU1(ICONST_0 + i);
+ else if (i >= Byte.MIN_VALUE && i <= Byte.MAX_VALUE)
+ {
+ putU1(BIPUSH);
+ putU1(i);
+ }
+ else
+ {
+ putU1(SIPUSH);
+ putU2(i);
+ }
+ }
+
+ /**
+ * Put bytecode to load a given local variable on the stream.
+ *
+ * @param i the slot to load
+ * @param type the base type of the load
+ */
+ private void putLoad(int i, Class type)
+ {
+ int offset = 0;
+ if (type == long.class)
+ offset = 1;
+ else if (type == float.class)
+ offset = 2;
+ else if (type == double.class)
+ offset = 3;
+ else if (! type.isPrimitive())
+ offset = 4;
+ if (i < 4)
+ putU1(ILOAD_0 + 4 * offset + i);
+ else
+ {
+ putU1(ILOAD + offset);
+ putU1(i);
+ }
+ }
+
+ /**
+ * Given a primitive type, return its wrapper class name.
+ *
+ * @param clazz the primitive type (but not void.class)
+ * @return the internal form of the wrapper class name
+ */
+ private String wrapper(Class clazz)
+ {
+ if (clazz == boolean.class)
+ return "java/lang/Boolean";
+ if (clazz == byte.class)
+ return "java/lang/Byte";
+ if (clazz == short.class)
+ return "java/lang/Short";
+ if (clazz == char.class)
+ return "java/lang/Character";
+ if (clazz == int.class)
+ return "java/lang/Integer";
+ if (clazz == long.class)
+ return "java/lang/Long";
+ if (clazz == float.class)
+ return "java/lang/Float";
+ if (clazz == double.class)
+ return "java/lang/Double";
+ // assert false;
+ return null;
+ }
+
+ /**
+ * Returns the entry of this String in the Constant pool, adding it
+ * if necessary.
+ *
+ * @param str the String to resolve
+ * @return the index of the String in the constant pool
+ */
+ private char utf8Info(String str)
+ {
+ String utf8 = toUtf8(str);
+ int len = utf8.length();
+ return poolIndex("\1" + (char) (len >> 8) + (char) (len & 0xff) + utf8);
+ }
+
+ /**
+ * Returns the entry of the appropriate class info structure in the
+ * Constant pool, adding it if necessary.
+ *
+ * @param name the class name, in internal form
+ * @return the index of the ClassInfo in the constant pool
+ */
+ private char classInfo(String name)
+ {
+ char index = utf8Info(name);
+ char[] c = {7, (char) (index >> 8), (char) (index & 0xff)};
+ return poolIndex(new String(c));
+ }
+
+ /**
+ * Returns the entry of the appropriate class info structure in the
+ * Constant pool, adding it if necessary.
+ *
+ * @param clazz the class type
+ * @return the index of the ClassInfo in the constant pool
+ */
+ private char classInfo(Class clazz)
+ {
+ return classInfo(TypeSignature.getEncodingOfClass(clazz.getName(),
+ false));
+ }
+
+ /**
+ * Returns the entry of the appropriate fieldref, methodref, or
+ * interfacemethodref info structure in the Constant pool, adding it
+ * if necessary.
+ *
+ * @param structure FIELD, METHOD, or INTERFACE
+ * @param clazz the class name, in internal form
+ * @param name the simple reference name
+ * @param type the type of the reference
+ * @return the index of the appropriate Info structure in the constant pool
+ */
+ private char refInfo(byte structure, String clazz, String name,
+ String type)
+ {
+ char cindex = classInfo(clazz);
+ char ntindex = nameAndTypeInfo(name, type);
+ // relies on FIELD == 1, METHOD == 2, INTERFACE == 3
+ char[] c = {(char) (structure + 8),
+ (char) (cindex >> 8), (char) (cindex & 0xff),
+ (char) (ntindex >> 8), (char) (ntindex & 0xff)};
+ return poolIndex(new String(c));
+ }
+
+ /**
+ * Returns the entry of the appropriate nameAndTyperef info structure
+ * in the Constant pool, adding it if necessary.
+ *
+ * @param name the simple name
+ * @param type the reference type
+ * @return the index of the NameAndTypeInfo structure in the constant pool
+ */
+ private char nameAndTypeInfo(String name, String type)
+ {
+ char nindex = utf8Info(name);
+ char tindex = utf8Info(type);
+ char[] c = {12, (char) (nindex >> 8), (char) (nindex & 0xff),
+ (char) (tindex >> 8), (char) (tindex & 0xff)};
+ return poolIndex(new String(c));
+ }
+
+ /**
+ * Converts a regular string to a UTF8 string, where the upper byte
+ * of every char is 0, and '\\u0000' is not in the string. This is
+ * basically to use a String as a fancy byte[], and while it is less
+ * efficient in memory use, it is easier for hashing.
+ *
+ * @param str the original, in straight unicode
+ * @return a modified string, in UTF8 format in the low bytes
+ */
+ private String toUtf8(String str)
+ {
+ final char[] ca = str.toCharArray();
+ final int len = ca.length;
+
+ // Avoid object creation, if str is already fits UTF8.
+ int i;
+ for (i = 0; i < len; i++)
+ if (ca[i] == 0 || ca[i] > '\u007f')
+ break;
+ if (i == len)
+ return str;
+
+ final StringBuffer sb = new StringBuffer(str);
+ sb.setLength(i);
+ for ( ; i < len; i++)
+ {
+ final char c = ca[i];
+ if (c > 0 && c <= '\u007f')
+ sb.append(c);
+ else if (c <= '\u07ff') // includes '\0'
+ {
+ sb.append((char) (0xc0 | (c >> 6)));
+ sb.append((char) (0x80 | (c & 0x6f)));
+ }
+ else
+ {
+ sb.append((char) (0xe0 | (c >> 12)));
+ sb.append((char) (0x80 | ((c >> 6) & 0x6f)));
+ sb.append((char) (0x80 | (c & 0x6f)));
+ }
+ }
+ return sb.toString();
+ }
+
+ /**
+ * Returns the location of a byte sequence (conveniently wrapped in
+ * a String with all characters between \u0001 and \u00ff inclusive)
+ * in the constant pool, adding it if necessary.
+ *
+ * @param sequence the byte sequence to look for
+ * @return the index of the sequence
+ * @throws IllegalArgumentException if this would make the constant
+ * pool overflow
+ */
+ private char poolIndex(String sequence)
+ {
+ Integer i = (Integer) poolEntries.get(sequence);
+ if (i == null)
+ {
+ // pool starts at index 1
+ int size = poolEntries.size() + 1;
+ if (size >= 65535)
+ throw new IllegalArgumentException("exceeds VM limitations");
+ i = new Integer(size);
+ poolEntries.put(sequence, i);
+ pool.append(sequence);
+ }
+ return (char) i.intValue();
+ }
+ } // class ClassFactory
+}
diff --git a/libjava/java/lang/reflect/UndeclaredThrowableException.java b/libjava/java/lang/reflect/UndeclaredThrowableException.java
new file mode 100644
index 0000000..d959692
--- /dev/null
+++ b/libjava/java/lang/reflect/UndeclaredThrowableException.java
@@ -0,0 +1,128 @@
+/* UndeclaredThrowableException.java -- wraps an undeclared checked exception
+ thrown by a Proxy invocation handler
+ Copyright (C) 2001, 2002 Free Software Foundation, Inc.
+
+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., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 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.reflect;
+
+/**
+ * This exception class is thrown by a {@link Proxy} instance if
+ * the {@link InvocationHandler#invoke(Object, Method, Object[]) invoke}
+ * method of that instance's InvocationHandler attempts to throw an
+ * exception that not declared by the throws clauses of all of the
+ * interface methods that the proxy instance is implementing.
+ *
+ * <p>When thrown by Proxy, this class will always wrap a checked
+ * exception, never {@link Error} or {@link RuntimeException},
+ * which are unchecked.
+ *
+ * @author Eric Blake <ebb9@email.byu.edu>
+ * @see Proxy
+ * @see InvocationHandler
+ * @since 1.3
+ * @status updated to 1.4
+ */
+public class UndeclaredThrowableException extends RuntimeException
+{
+ /**
+ * Compatible with JDK 1.3+.
+ */
+ private static final long serialVersionUID = 330127114055056639L;
+
+ /**
+ * The immutable exception that this wraps. This field is redundant
+ * with {@link Throwable#cause}, but is necessary for serial compatibility.
+ *
+ * @serial the chained exception
+ */
+ private final Throwable undeclaredThrowable;
+
+ /**
+ * Wraps the given checked exception into a RuntimeException, with no
+ * detail message. {@link Throwable#initCause(Throwable)} will fail
+ * on this instance.
+ *
+ * @param cause the undeclared throwable that caused this exception,
+ * may be null
+ */
+ public UndeclaredThrowableException(Throwable cause)
+ {
+ this(cause, null);
+ }
+
+ /**
+ * Wraps the given checked exception into a RuntimeException, with the
+ * specified detail message. {@link Throwable#initCause(Throwable)} will
+ * fail on this instance.
+ *
+ * @param cause the undeclared throwable that caused this exception,
+ * may be null
+ * @param message the message, may be null
+ */
+ public UndeclaredThrowableException(Throwable cause, String message)
+ {
+ super(message, cause);
+ undeclaredThrowable = cause;
+ }
+
+ /**
+ * Returns the cause of this exception. If this exception was created
+ * by a {@link Proxy} instance, it will be a non-null checked
+ * exception. This method pre-dates exception chaining, and is now
+ * simply a longer way to call <code>getCause()</code>.
+ *
+ * @return the cause of this exception, may be null
+ * @see #getCause()
+ */
+ public Throwable getUndeclaredThrowable()
+ {
+ return undeclaredThrowable;
+ }
+
+ /**
+ * Returns the cause of this exception. If this exception was created
+ * by a {@link Proxy} instance, it will be a non-null checked
+ * exception.
+ *
+ * @return the cause of this exception, may be null
+ * @since 1.4
+ */
+ public Throwable getCause()
+ {
+ return undeclaredThrowable;
+ }
+}
diff --git a/libjava/java/lang/reflect/natProxy.cc b/libjava/java/lang/reflect/natProxy.cc
new file mode 100644
index 0000000..1a24858
--- /dev/null
+++ b/libjava/java/lang/reflect/natProxy.cc
@@ -0,0 +1,38 @@
+// natProxy.cc - Native code for Proxy class.
+
+/* Copyright (C) 2002 Free Software Foundation
+
+ This file is part of libgcj.
+
+This software is copyrighted work licensed under the terms of the
+Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
+details. */
+
+#include <config.h>
+
+#include <gcj/cni.h>
+#include <jvm.h>
+
+#include <java/lang/Class.h>
+#include <java/lang/ClassLoader.h>
+#include <java/lang/reflect/Proxy.h>
+#include <java/lang/reflect/Proxy$ProxyData.h>
+
+::java::lang::Class *
+java::lang::reflect::Proxy::getProxyClass0 (::java::lang::ClassLoader *, JArray< ::java::lang::Class *> *)
+{
+ return 0;
+}
+
+::java::lang::reflect::Proxy$ProxyData *
+java::lang::reflect::Proxy::getProxyData0 (::java::lang::ClassLoader *, JArray< ::java::lang::Class *> *)
+{
+ return 0;
+}
+
+::java::lang::Class *
+java::lang::reflect::Proxy::generateProxyClass0 (::java::lang::ClassLoader *,
+ ::java::lang::reflect::Proxy$ProxyData *)
+{
+ return 0;
+}
--
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