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    
015    package org.apache.tapestry5.ioc.services;
016    
017    import org.apache.tapestry5.ioc.AnnotationAccess;
018    import org.apache.tapestry5.ioc.MethodAdvice;
019    
020    /**
021     * A decorator used to create an interceptor that delegates each method's invocation to an
022     * {@link org.apache.tapestry5.ioc.MethodAdvice} for advice. Advice can inspect or change method parameters, inspect or
023     * change
024     * the method's return value, and inspect and change thrown exceptions (checked and unchecked).
025     */
026    public interface AspectDecorator
027    {
028        /**
029         * Intercepts method invocations on the delegate and passes them through the provided aspect. Note that the advice
030         * <em>must</em> be thread-safe.
031         * 
032         * @param serviceInterface
033         *            defines the interface of the interceptor and delegate
034         * @param delegate
035         *            the object on which methods will be invoked
036         * @param advice
037         *            intercepts the method invocations on the delegate
038         * @param description
039         *            used as the toString() of the returned interceptor, unless toString() is part of the
040         *            service interface
041         * @return the interceptor, wrapping the delegate with all the advice
042         */
043        <T> T build(Class<T> serviceInterface, T delegate, MethodAdvice advice, String description);
044    
045        /**
046         * Creates a builder that can be used to create the interceptor. This is used when only some of the methods need to
047         * be advised, or when different methods need to receive different advice, or when multiple advice is to be
048         * applied.
049         * 
050         * @param serviceInterface
051         *            defines the interface of the interceptor and the delegate
052         * @param delegate
053         *            the object on which methods will be invokes
054         * @param description
055         *            used as the toString() of the interceptor unless toString() is part of the service
056         *            interface
057         * @return a builder that can be used to generate the final interceptor
058         */
059        <T> AspectInterceptorBuilder<T> createBuilder(Class<T> serviceInterface, T delegate, String description);
060    
061        /**
062         * Creates a builder that can be used to create the interceptor. This is used when only some of the methods need to
063         * be advised, or when different methods need to receive different advice, or when multiple advice is to be
064         * applied.
065         * 
066         * @param serviceInterface
067         *            defines the interface of the interceptor and the delegate
068         * @param delegate
069         *            the object on which methods will be invokes
070         * @param annotationAccess
071         *            provides access to combined annotations of the underlying service
072         *            and service interface
073         * @param description
074         *            used as the toString() of the interceptor unless toString() is part of the service
075         *            interface
076         * @return a builder that can be used to generate the final interceptor
077         */
078        <T> AspectInterceptorBuilder<T> createBuilder(Class<T> serviceInterface, T delegate,
079                AnnotationAccess annotationAccess, String description);
080    }