001// Copyright 2008, 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.Log;
018import org.apache.tapestry5.ioc.internal.services.LoggingAdvice;
019import org.apache.tapestry5.ioc.services.ExceptionTracker;
020import org.apache.tapestry5.model.MutableComponentModel;
021import org.apache.tapestry5.plastic.MethodAdvice;
022import org.apache.tapestry5.plastic.PlasticClass;
023import org.apache.tapestry5.plastic.PlasticMethod;
024import org.apache.tapestry5.services.transform.ComponentClassTransformWorker2;
025import org.apache.tapestry5.services.transform.TransformationSupport;
026
027import java.util.List;
028
029/**
030 * Looks for the {@link org.apache.tapestry5.annotations.Log} marker annotation and adds method advice to perform the
031 * logging. This is similar to what the {@link org.apache.tapestry5.ioc.services.LoggingDecorator} does for service
032 * interface methods.
033 */
034public class LogWorker implements ComponentClassTransformWorker2
035{
036    private final ExceptionTracker exceptionTracker;
037
038    public LogWorker(ExceptionTracker exceptionTracker)
039    {
040        this.exceptionTracker = exceptionTracker;
041    }
042
043    public void transform(PlasticClass plasticClass, TransformationSupport support, MutableComponentModel model)
044    {
045        List<PlasticMethod> methods = plasticClass.getMethodsWithAnnotation(Log.class);
046
047        if (methods.isEmpty())
048        {
049            return;
050        }
051
052        final MethodAdvice loggingAdvice = new LoggingAdvice(model.getLogger(), exceptionTracker);
053
054        for (PlasticMethod method : methods)
055        {
056            method.addAdvice(loggingAdvice);
057        }
058    }
059}