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.services; 016 017import java.lang.annotation.Annotation; 018import java.lang.reflect.Type; 019 020import org.apache.tapestry5.internal.InternalPropertyConduit; 021import org.apache.tapestry5.ioc.AnnotationProvider; 022import org.apache.tapestry5.ioc.services.TypeCoercer; 023 024/** 025 * A PropertyConduit for a literal value in an expression, such as a number, or "true", "false" or "null". 026 */ 027public class LiteralPropertyConduit extends PropertyConduitDelegate implements InternalPropertyConduit 028{ 029 private final Class propertyType; 030 031 private final AnnotationProvider annotationProvider; 032 033 private final String description; 034 035 private final Object value; 036 037 public LiteralPropertyConduit(TypeCoercer typeCoercer, Class propertyType, AnnotationProvider annotationProvider, 038 String description, Object value) 039 { 040 super(typeCoercer); 041 042 this.propertyType = propertyType; 043 this.annotationProvider = annotationProvider; 044 this.description = description; 045 046 this.value = value; 047 } 048 049 public Object get(Object instance) 050 { 051 return value; 052 } 053 054 public void set(Object instance, Object value) 055 { 056 throw new RuntimeException("Literal values are not updateable."); 057 } 058 059 public Class getPropertyType() 060 { 061 return propertyType; 062 } 063 064 public Type getPropertyGenericType() 065 { 066 return propertyType; 067 } 068 069 public <T extends Annotation> T getAnnotation(Class<T> annotationClass) 070 { 071 return annotationProvider.getAnnotation(annotationClass); 072 } 073 074 public String getPropertyName() 075 { 076 return null; 077 } 078 079 @Override 080 public String toString() 081 { 082 return description; 083 } 084 085}