/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* 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 Rhino code, released
* May 6, 1999.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1997-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Igor Bukanov
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (the "GPL"), in which
* case the provisions of the GPL are applicable instead of those above. If
* you wish to allow use of your version of this file only under the terms of
* the GPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replacing
* them with the notice and other provisions required by the GPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
package org.mozilla.javascript;
import java.lang.reflect.Method;
/**
* Adapter to use JS function as implementation of Java interfaces with
* single method or multiple methods with the same signature.
*/
public class InterfaceAdapter
{
private final Object proxyHelper;
/**
* Make glue object implementing interface cl that will
* call the supplied JS function when called.
* Only interfaces were all methods have the same signature is supported.
*
* @return The glue object or null if <tt>cl</tt> is not interface or
* has methods with different signatures.
*/
static Object create(Context cx, Class cl, Callable function)
{
if (!cl.isInterface()) throw new IllegalArgumentException();
Scriptable topScope = ScriptRuntime.getTopCallScope(cx);
ClassCache cache = ClassCache.get(topScope);
InterfaceAdapter adapter;
adapter = (InterfaceAdapter)cache.getInterfaceAdapter(cl);
ContextFactory cf = cx.getFactory();
if (adapter == null) {
Method[] methods = cl.getMethods();
if (methods.length == 0) {
throw Context.reportRuntimeError2(
"msg.no.empty.interface.conversion",
String.valueOf(function),
cl.getClass().getName());
}
boolean canCallFunction = false;
canCallFunctionChecks: {
Class[] argTypes = methods[0].getParameterTypes();
// check that the rest of methods has the same signature
for (int i = 1; i != methods.length; ++i) {
Class[] types2 = methods[i].getParameterTypes();
if (types2.length != argTypes.length) {
break canCallFunctionChecks;
}
for (int j = 0; j != argTypes.length; ++j) {
if (types2[j] != argTypes[j]) {
break canCallFunctionChecks;
}
}
}
canCallFunction= true;
}
if (!canCallFunction) {
throw Context.reportRuntimeError2(
"msg.no.function.interface.conversion",
String.valueOf(function),
cl.getClass().getName());
}
adapter = new InterfaceAdapter(cf, cl);
cache.cacheInterfaceAdapter(cl, adapter);
}
return VMBridge.instance.newInterfaceProxy(
adapter.proxyHelper, cf, adapter, function, topScope);
}
private InterfaceAdapter(ContextFactory cf, Class cl)
{
this.proxyHelper
= VMBridge.instance.getInterfaceProxyHelper(
cf, new Class[] { cl });
}
public Object invoke(ContextFactory cf,
final Object target,
final Scriptable topScope,
final Method method,
final Object[] args)
{
ContextAction action = new ContextAction() {
public Object run(Context cx)
{
return invokeImpl(cx, target, topScope, method, args);
}
};
return cf.call(action);
}
Object invokeImpl(Context cx,
Object target,
Scriptable topScope,
Method method,
Object[] args)
{
int N = (args == null) ? 0 : args.length;
Callable function = (Callable)target;
Scriptable thisObj = topScope;
Object[] jsargs = new Object[N + 1];
jsargs[N] = method.getName();
if (N != 0) {
WrapFactory wf = cx.getWrapFactory();
for (int i = 0; i != N; ++i) {
jsargs[i] = wf.wrap(cx, topScope, args[i], null);
}
}
Object result = function.call(cx, topScope, thisObj, jsargs);
Class javaResultType = method.getReturnType();
if (javaResultType == Void.TYPE) {
result = null;
} else {
result = Context.jsToJava(result, javaResultType);
}
return result;
}
}
