001// Copyright 2010, 2011 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007// http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry5.internal.transform;
016
017import org.apache.tapestry5.annotations.HeartbeatDeferred;
018import org.apache.tapestry5.model.MutableComponentModel;
019import org.apache.tapestry5.plastic.MethodAdvice;
020import org.apache.tapestry5.plastic.MethodInvocation;
021import org.apache.tapestry5.plastic.PlasticClass;
022import org.apache.tapestry5.plastic.PlasticMethod;
023import org.apache.tapestry5.services.Heartbeat;
024import org.apache.tapestry5.services.transform.ComponentClassTransformWorker2;
025import org.apache.tapestry5.services.transform.TransformationSupport;
026
027public class HeartbeatDeferredWorker implements ComponentClassTransformWorker2
028{
029    private final Heartbeat heartbeat;
030
031    private final MethodAdvice deferredAdvice = new MethodAdvice()
032    {
033        public void advise(final MethodInvocation invocation)
034        {
035            heartbeat.defer(new Runnable()
036            {
037                public void run()
038                {
039                    invocation.proceed();
040                }
041            });
042        }
043    };
044
045    public HeartbeatDeferredWorker(Heartbeat heartbeat)
046    {
047        this.heartbeat = heartbeat;
048    }
049
050    public void transform(PlasticClass plasticClass, TransformationSupport support, MutableComponentModel model)
051    {
052        for (PlasticMethod method : plasticClass.getMethodsWithAnnotation(HeartbeatDeferred.class))
053        {
054            deferMethodInvocations(method);
055        }
056    }
057
058    void deferMethodInvocations(PlasticMethod method)
059    {
060        validateVoid(method);
061
062        validateNoCheckedExceptions(method);
063
064        method.addAdvice(deferredAdvice);
065
066    }
067
068    private void validateNoCheckedExceptions(PlasticMethod method)
069    {
070        if (method.getDescription().checkedExceptionTypes.length > 0)
071            throw new RuntimeException(
072                    String.format(
073                            "Method %s is not compatible with the @HeartbeatDeferred annotation, as it throws checked exceptions.",
074                            method.getMethodIdentifier()));
075    }
076
077    private void validateVoid(PlasticMethod method)
078    {
079        if (!method.isVoid())
080            throw new RuntimeException(String.format(
081                    "Method %s is not compatible with the @HeartbeatDeferred annotation, as it is not a void method.",
082                    method.getMethodIdentifier()));
083    }
084}