/*******************************************************************************
* Copyright 2011 Google Inc. All Rights Reserved.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*******************************************************************************/
package com.google.gwt.dev.shell.mac;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Field;
import java.util.Collection;
import org.apache.commons.collections.CollectionUtils;
import org.apache.commons.collections.Predicate;
import com.google.gdt.eclipse.designer.mac.BrowserShellMac;
import com.google.gdt.eclipse.designer.mac.BrowserShellMac.DispatchMethod;
import com.google.gdt.eclipse.designer.mac.BrowserShellMac.DispatchObject;
import com.google.gwt.dev.shell.CompilingClassLoader;
import com.google.gwt.dev.shell.DispatchClassInfo;
import com.google.gwt.dev.shell.JavaDispatch;
import com.google.gwt.dev.shell.JavaDispatchImpl;
import com.google.gwt.dev.shell.JsValue;
import com.google.gwt.dev.shell.JsValueGlue;
import com.google.gwt.dev.shell.Jsni;
import com.google.gwt.dev.shell.MethodAdaptor;
/**
* Wraps an arbitrary Java Object as a Dispatch component. The class was
* motivated by the need to expose Java objects into JavaScript.
*
* An instance of this class with no target is used to globally access all
* static methods or fields.
*/
class WebKitDispatchAdapter implements DispatchObject {
protected final CompilingClassLoader classLoader;
protected final JavaDispatch javaDispatch;
/**
* This constructor initializes as the static dispatcher, which handles only
* static method calls and field references.
*
* @param cl this class's classLoader
*/
protected WebKitDispatchAdapter(CompilingClassLoader cl) {
javaDispatch = new JavaDispatchImpl(cl);
this.classLoader = cl;
}
/**
* This constructor initializes a dispatcher, around a particular instance.
*
* @param cl this class's classLoader
* @param target the object being wrapped as an IDispatch
*/
WebKitDispatchAdapter(CompilingClassLoader cl, Object target) {
javaDispatch = new JavaDispatchImpl(cl, target);
this.classLoader = cl;
}
public final CompilingClassLoader getClassLoader() {
return classLoader;
}
public long getField(String member) {
int dispId = getDispId(member);
if (dispId < 0) {
return BrowserShellMac.jsUndefined();
}
if (!javaDispatch.isField(dispId)) {
return BrowserShellMac.jsUndefined();
}
Field field = javaDispatch.getField(dispId);
JsValueSaf jsValue = new JsValueSaf();
JsValueGlue.set(jsValue, classLoader, field.getType(),
javaDispatch.getFieldValue(dispId));
long jsval = jsValue.getJsValue();
return jsval;
}
public Object getWrappedMethod(String member) {
int dispId = getDispId(member);
if (dispId < 0) {
return null;
}
if (!javaDispatch.isMethod(dispId)) {
return null;
}
final MethodAdaptor method = javaDispatch.getMethod(dispId);
AccessibleObject obj = method.getUnderlyingObject();
DispatchMethod dispMethod = (DispatchMethod) classLoader.getWrapperForObject(obj);
if (dispMethod == null) {
dispMethod = new MethodDispatch(classLoader, method);
classLoader.putWrapperForObject(obj, dispMethod);
}
return dispMethod;
}
@SuppressWarnings("unchecked")
public String[] getFields() {
try {
DispatchClassInfo classInfo =
classLoader.getClassInfoFromClassName(getTarget().getClass().getName());
Collection<Field> selected = CollectionUtils.select(classInfo.getMembers(), new Predicate() {
public boolean evaluate(Object object) {
return object instanceof Field;
}
});
String[] result = new String[selected.size()];
int index = 0;
for (Field field : selected) {
String jsFieldName = "@" + field.getDeclaringClass().getName() + "::" + field.getName();
result[index++] = Jsni.WBP_MEMBER + classLoader.getDispId(jsFieldName);
}
return result;
} catch (Throwable e) {
return new String[0];
}
}
public Object getTarget() {
return javaDispatch.getTarget();
}
public void setField(String member, long value) {
JsValue jsValue = new JsValueSaf(value);
int dispId = getDispId(member);
if (dispId < 0) {
// TODO (knorton): We could allow expandos, but should we?
throw new RuntimeException("No such field " + member);
}
if (javaDispatch.isMethod(dispId)) {
throw new RuntimeException("Cannot reassign method " + member);
}
Field field = javaDispatch.getField(dispId);
Object val = JsValueGlue.get(jsValue, classLoader, field.getType(),
"setField");
javaDispatch.setFieldValue(dispId, val);
}
@Override
public String toString() {
return getTarget().toString();
}
private int getDispId(String member) {
if (member.startsWith(Jsni.WBP_MEMBER)) {
try {
return Integer.valueOf(member.substring(Jsni.WBP_MEMBER.length()));
} catch (Throwable e) {
return -1;
}
} else {
return classLoader.getDispId(member);
}
}
}