001// Copyright 2005 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.tapestry.annotations; 016 017import java.lang.reflect.Method; 018 019import org.apache.hivemind.Location; 020import org.apache.hivemind.Resource; 021import org.apache.tapestry.enhance.EnhancementOperation; 022import org.apache.tapestry.spec.IComponentSpecification; 023import org.apache.tapestry.spec.IPropertySpecification; 024import org.apache.tapestry.spec.PropertySpecification; 025 026/** 027 * Looks for {@link org.apache.tapestry.annotations.InitialValue} annotations on methods that don't 028 * have a {@link org.apache.tapestry.annotations.Persist} annotation (that's handled by 029 * {@link org.apache.tapestry.annotations.PersistAnnotationWorker}); adds an 030 * {@link org.apache.tapestry.spec.IPropertySpecification} for the property, so that its initial 031 * value may be set. 032 * 033 * @author Howard M. Lewis Ship 034 * @since 4.0 035 */ 036public class InitialValueAnnotationWorker implements SecondaryAnnotationWorker 037{ 038 /** 039 * Returns true if the method has the InitialValue annotation. 040 */ 041 public boolean canEnhance(Method method) 042 { 043 return method.getAnnotation(InitialValue.class) != null; 044 } 045 046 public void peformEnhancement(EnhancementOperation op, IComponentSpecification spec, 047 Method method, Resource classResource) 048 { 049 InitialValue iv = method.getAnnotation(InitialValue.class); 050 051 if (iv == null) 052 return; 053 054 if (method.getAnnotation(Persist.class) != null) 055 return; 056 057 Location location = AnnotationUtils.buildLocationForAnnotation(method, iv, classResource); 058 059 String propertyName = AnnotationUtils.getPropertyName(method); 060 061 // Define a transient property 062 063 IPropertySpecification pspec = new PropertySpecification(); 064 065 pspec.setName(propertyName); 066 pspec.setLocation(location); 067 pspec.setInitialValue(iv.value()); 068 069 spec.addPropertySpecification(pspec); 070 } 071}