/*
* Copyright 2009 JBoss, a divison Red Hat, Inc
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* 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 org.jboss.errai.cdi.rebind;
import com.google.gwt.core.ext.typeinfo.JMethod;
import com.google.gwt.core.ext.typeinfo.JParameter;
import org.jboss.errai.bus.client.api.Message;
import org.jboss.errai.bus.client.api.MessageCallback;
import org.jboss.errai.bus.client.framework.MessageBus;
import org.jboss.errai.cdi.client.CDIProtocol;
import org.jboss.errai.ioc.client.api.CodeDecorator;
import org.jboss.errai.ioc.rebind.ioc.Decorator;
import org.jboss.errai.ioc.rebind.ioc.InjectionContext;
import org.jboss.errai.ioc.rebind.ioc.InjectionPoint;
import javax.enterprise.event.Observes;
/**
*
* Generates the boiler plate for @Observes annotations use in GWT clients.<br/>
* Basically creates a subscription for a CDI event type that invokes on the annotated method.
*
* @author: Heiko Braun <hbraun@redhat.com>
* @date: Jul 27, 2010
*/
@CodeDecorator
public class ObservesDecorator extends Decorator<Observes> {
public ObservesDecorator(Class<Observes> decoratesWith) {
super(decoratesWith);
}
@Override
public String generateDecorator(InjectionPoint<Observes> injectionPoint) {
final InjectionContext ctx = injectionPoint.getInjectionContext();
final JMethod method = injectionPoint.getMethod();
final JParameter parm = injectionPoint.getParm();
String parmClassName = parm.getType().getQualifiedSourceName();
String varName = injectionPoint.getInjector().getVarName();
// Get an instance of the message bus.
final String messageBusInst = ctx.getInjector(ctx
.getProcessingContext().loadClassType(MessageBus.class)).getType(ctx, injectionPoint);
return messageBusInst + ".subscribe(\"cdi.event:" + parmClassName + "\", new " + MessageCallback.class.getName() + "() {\n" +
" public void callback(" + Message.class.getName() + " message) {\n" +
" java.lang.Object response = message.get(" + parmClassName + ".class, " + CDIProtocol.class.getName() + "." + CDIProtocol.OBJECT_REF.name() + ");\n" +
" " + varName + "." + method.getName() + "((" + parmClassName + ") response);\n" +
" }\n" +
" });";
}
}