001    // Copyright 2007, 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    
015    package org.apache.tapestry5.annotations;
016    
017    
018    import java.lang.annotation.Documented;
019    import static java.lang.annotation.ElementType.FIELD;
020    import static java.lang.annotation.ElementType.PARAMETER;
021    import java.lang.annotation.Retention;
022    import static java.lang.annotation.RetentionPolicy.RUNTIME;
023    import java.lang.annotation.Target;
024    
025    import static org.apache.tapestry5.ioc.annotations.AnnotationUseContext.*;
026    
027    import org.apache.tapestry5.ioc.annotations.Inject;
028    import org.apache.tapestry5.ioc.annotations.UseWith;
029    
030    /**
031     * Used in conjunction with the {@link Inject} annotation to identify a service <em>by name</em> and not by type. This
032     * is most useful when there are multiple services with the same service interface and a particular one needs to be
033     * selected.
034     */
035    @Target(
036            { FIELD, PARAMETER })
037    @Documented
038    @Retention(RUNTIME)
039    @UseWith({COMPONENT,MIXIN,PAGE,SERVICE})
040    public @interface Service
041    {
042        /**
043         * The name of the service. Symbols will be expanded and case is not relevant.
044         */
045        String value();
046    }