    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}