001// Copyright 2007, 2008, 2009, 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.ioc.annotations; 016 017import java.lang.annotation.Documented; 018import java.lang.annotation.Retention; 019import java.lang.annotation.Target; 020 021import static java.lang.annotation.ElementType.FIELD; 022import static java.lang.annotation.ElementType.PARAMETER; 023import static java.lang.annotation.RetentionPolicy.RUNTIME; 024import static org.apache.tapestry5.ioc.annotations.AnnotationUseContext.*; 025 026/** 027 * Used to inject a symbol value, via a symbol name. This is used much like {@link 028 * org.apache.tapestry5.ioc.annotations.Value} annotation, except that symbols are not expanded ... the entire value is 029 * a symbol name. This allows the annotation to reference a public constant variable. 030 * <p/> 031 * <p/> 032 * The injected value may be coerced from string to an alternate type (defined by the field or parameter to which 033 * the @Symbol annotation is attached). For better control, use the {@link IntermediateType} annotation as well, which 034 * allows the string to be coerced to an alternate type before being coerced a second time to the field or parameter type. 035 */ 036@Target( 037 {PARAMETER, FIELD}) 038@Retention(RUNTIME) 039@Documented 040@UseWith({COMPONENT, MIXIN, PAGE, SERVICE}) 041public @interface Symbol 042{ 043 /** 044 * The name of the symbol to inject. 045 */ 046 String value(); 047}