mirror of
https://github.com/rn10950/RetroZilla.git
synced 2024-11-13 03:10:10 +01:00
259 lines
8.9 KiB
Java
259 lines
8.9 KiB
Java
/* ***** BEGIN LICENSE BLOCK *****
|
|
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
|
|
*
|
|
* The contents of this file are subject to the Mozilla Public License Version
|
|
* 1.1 (the "License"); you may not use this file except in compliance with
|
|
* the License. You may obtain a copy of the License at
|
|
* http://www.mozilla.org/MPL/
|
|
*
|
|
* Software distributed under the License is distributed on an "AS IS" basis,
|
|
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
|
|
* for the specific language governing rights and limitations under the
|
|
* License.
|
|
*
|
|
* The Original Code is Java XPCOM Bindings.
|
|
*
|
|
* The Initial Developer of the Original Code is
|
|
* IBM Corporation.
|
|
* Portions created by the Initial Developer are Copyright (C) 2004
|
|
* IBM Corporation. All Rights Reserved.
|
|
*
|
|
* Contributor(s):
|
|
* Javier Pedemonte (jhpedemonte@gmail.com)
|
|
*
|
|
* Alternatively, the contents of this file may be used under the terms of
|
|
* either the GNU General Public License Version 2 or later (the "GPL"), or
|
|
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
|
|
* in which case the provisions of the GPL or the LGPL are applicable instead
|
|
* of those above. If you wish to allow use of your version of this file only
|
|
* under the terms of either the GPL or the LGPL, and not to allow others to
|
|
* use your version of this file under the terms of the MPL, indicate your
|
|
* decision by deleting the provisions above and replace them with the notice
|
|
* and other provisions required by the GPL or the LGPL. If you do not delete
|
|
* the provisions above, a recipient may use your version of this file under
|
|
* the terms of any one of the MPL, the GPL or the LGPL.
|
|
*
|
|
* ***** END LICENSE BLOCK ***** */
|
|
|
|
package org.mozilla.xpcom.internal;
|
|
|
|
import java.lang.reflect.InvocationHandler;
|
|
import java.lang.reflect.Method;
|
|
import java.lang.reflect.Proxy;
|
|
|
|
import org.mozilla.xpcom.XPCOMException;
|
|
|
|
|
|
/**
|
|
* This class is used to pass XPCOM objects to Java functions. A
|
|
* <code>java.lang.reflect.Proxy</code> instance is created using the expected
|
|
* interface, and all calls to the proxy are forwarded to the XPCOM object.
|
|
*/
|
|
public class XPCOMJavaProxy implements InvocationHandler {
|
|
|
|
/**
|
|
* Pointer to the XPCOM object for which we are a proxy.
|
|
*/
|
|
protected long nativeXPCOMPtr;
|
|
|
|
/**
|
|
* Default constructor.
|
|
*
|
|
* @param aXPCOMInstance address of XPCOM object as a long
|
|
*/
|
|
public XPCOMJavaProxy(long aXPCOMInstance) {
|
|
nativeXPCOMPtr = aXPCOMInstance;
|
|
}
|
|
|
|
/**
|
|
* Returns the XPCOM object that the given proxy references.
|
|
*
|
|
* @param aProxy Proxy created by <code>createProxy</code>
|
|
*
|
|
* @return address of XPCOM object as a long
|
|
*/
|
|
protected static long getNativeXPCOMInstance(Object aProxy) {
|
|
XPCOMJavaProxy proxy = (XPCOMJavaProxy) Proxy.getInvocationHandler(aProxy);
|
|
return proxy.nativeXPCOMPtr;
|
|
}
|
|
|
|
/**
|
|
* Creates a Proxy for the given XPCOM object.
|
|
*
|
|
* @param aInterface interface from which to create Proxy
|
|
* @param aXPCOMInstance address of XPCOM object as a long
|
|
*
|
|
* @return Proxy of given XPCOM object
|
|
*/
|
|
protected static Object createProxy(Class aInterface, long aXPCOMInstance) {
|
|
// XXX We should really get the class loader from |aInterface|. However,
|
|
// that class loader doesn't know about |XPCOMJavaProxyBase|. So for
|
|
// now, we get the class loader that loaded |XPCOMJavaProxy|. When
|
|
// we get rid of the "XPCOMJavaProxyBase.java" class, we can revert
|
|
// to the old method below.
|
|
// return Proxy.newProxyInstance(aInterface.getClassLoader(),
|
|
return Proxy.newProxyInstance(XPCOMJavaProxy.class.getClassLoader(),
|
|
new Class[] { aInterface, XPCOMJavaProxyBase.class },
|
|
new XPCOMJavaProxy(aXPCOMInstance));
|
|
}
|
|
|
|
/**
|
|
* All calls to the Java proxy are forwarded to this method. This method
|
|
* takes care of a few of the <code>Object</code> method calls; all other
|
|
* calls are forwarded to the XPCOM object.
|
|
*
|
|
* @param aProxy Proxy created by <code>createProxy</code>
|
|
* @param aMethod object that describes the called method
|
|
* @param aParams array of the arguments passed to the method
|
|
*
|
|
* @return return value as defined by given <code>aMethod</code>
|
|
*/
|
|
public Object invoke(Object aProxy, Method aMethod, Object[] aParams)
|
|
throws Throwable {
|
|
String methodName = aMethod.getName();
|
|
|
|
// Handle the three java.lang.Object methods that are passed to us.
|
|
if (aMethod.getDeclaringClass() == Object.class) {
|
|
if (methodName.equals("hashCode")) {
|
|
return proxyHashCode(aProxy);
|
|
}
|
|
if (methodName.equals("equals")) {
|
|
return proxyEquals(aProxy, aParams[0]);
|
|
}
|
|
if (methodName.equals("toString")) {
|
|
return proxyToString(aProxy);
|
|
}
|
|
System.err.println("WARNING: Unhandled Object method [" +
|
|
methodName + "]");
|
|
return null;
|
|
}
|
|
|
|
// Handle the 'finalize' method called during garbage collection
|
|
if (aMethod.getDeclaringClass() == XPCOMJavaProxyBase.class) {
|
|
if (methodName.equals("finalize")) {
|
|
finalizeProxy(aProxy);
|
|
} else {
|
|
System.err.println("WARNING: Unhandled XPCOMJavaProxyBase method [" +
|
|
methodName + "]");
|
|
}
|
|
return null;
|
|
}
|
|
|
|
// If not already handled, pass method calls to XPCOM object.
|
|
return callXPCOMMethod(aProxy, methodName, aParams);
|
|
}
|
|
|
|
/**
|
|
* Handles method calls of <code>java.lang.Object.hashCode</code>
|
|
*
|
|
* @param aProxy Proxy created by <code>createProxy</code>
|
|
*
|
|
* @return Integer object representing hash code of given object
|
|
*
|
|
* @see Object#hashCode()
|
|
*/
|
|
protected static Integer proxyHashCode(Object aProxy) {
|
|
return new Integer(System.identityHashCode(aProxy));
|
|
}
|
|
|
|
/**
|
|
* Handles method calls of <code>java.lang.Object.equals</code>
|
|
*
|
|
* @param aProxy Proxy created by <code>createProxy</code>
|
|
* @param aOther another object
|
|
*
|
|
* @return <code>true</code> if the given objects are the same;
|
|
* <code>false</code> otherwise
|
|
*
|
|
* @see Object#equals(Object)
|
|
*/
|
|
protected static Boolean proxyEquals(Object aProxy, Object aOther) {
|
|
// See if the two are the same Java object
|
|
if (aProxy == aOther) {
|
|
return Boolean.TRUE;
|
|
} else {
|
|
// If not, then see if they represent the same XPCOM object. But first,
|
|
// we need to check if |aOther| is an XPCOMJavaProxy.
|
|
if (isXPCOMJavaProxy(aOther) && isSameXPCOMObject(aProxy, aOther)) {
|
|
return Boolean.TRUE;
|
|
}
|
|
}
|
|
return Boolean.FALSE;
|
|
}
|
|
|
|
/**
|
|
* Indicates whether the given object is an XPCOMJavaProxy.
|
|
*
|
|
* @param aObject object to check
|
|
*
|
|
* @return <code>true</code> if the given object is an XPCOMJavaProxy;
|
|
* <code>false</code> otherwise
|
|
*/
|
|
protected static boolean isXPCOMJavaProxy(Object aObject) {
|
|
if (aObject != null && Proxy.isProxyClass(aObject.getClass())) {
|
|
InvocationHandler h = Proxy.getInvocationHandler(aObject);
|
|
if (h instanceof XPCOMJavaProxy) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Checks if the two given XPCOMJavaProxy objects are proxies for
|
|
* the same XPCOM object.
|
|
*
|
|
* @param aProxy1 XPCOMJavaProxy created by <code>createProxy</code>
|
|
* @param aProxy2 XPCOMJavaProxy created by <code>createProxy</code>
|
|
*
|
|
* @return <code>true</code> if both proxies represent the same XPCOM object;
|
|
* <code>false</code> otherwise
|
|
*/
|
|
protected static native boolean isSameXPCOMObject(Object aProxy1,
|
|
Object aProxy2);
|
|
|
|
/**
|
|
* Handles method calls of <code>java.lang.Object.toString</code>
|
|
*
|
|
* @param aProxy Proxy created by <code>createProxy</code>
|
|
*
|
|
* @return String representation of given object
|
|
*
|
|
* @see Object#toString()
|
|
*/
|
|
protected static String proxyToString(Object aProxy) {
|
|
return aProxy.getClass().getInterfaces()[0].getName() + '@' +
|
|
Integer.toHexString(aProxy.hashCode());
|
|
}
|
|
|
|
/**
|
|
* Called when the proxy is garbage collected by the JVM. Allows us to clean
|
|
* up any references to the XPCOM object.
|
|
*
|
|
* @param aProxy reference to Proxy that is being garbage collected
|
|
*/
|
|
protected void finalizeProxy(Object aProxy) throws Throwable {
|
|
finalizeProxyNative(aProxy);
|
|
super.finalize();
|
|
}
|
|
|
|
protected static native void finalizeProxyNative(Object aProxy);
|
|
|
|
/**
|
|
* Calls the XPCOM object referenced by the proxy with the given method.
|
|
*
|
|
* @param aProxy Proxy created by <code>createProxy</code>
|
|
* @param aMethodName name of method that we want to call
|
|
* @param aParams array of params passed to method
|
|
*
|
|
* @return return value as defined by given method
|
|
*
|
|
* @exception XPCOMException if XPCOM method failed. Values of XPCOMException
|
|
* are defined by the method called.
|
|
*/
|
|
protected static native Object callXPCOMMethod(Object aProxy,
|
|
String aMethodName, Object[] aParams);
|
|
|
|
}
|
|
|