1 /* 2 * Copyright 2005 the original author or authors. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package org.springframework.ws.server; 18 19 import org.springframework.ws.context.MessageContext; 20 21 /** 22 * Workflow interface that allows for customized endpoint invocation chains. Applications can register any number of 23 * existing or custom interceptors for certain groups of endpoints, to add common preprocessing behavior without needing 24 * to modify each endpoint implementation. 25 * <p/> 26 * An <code>EndpointInterceptor</code> gets called before the appropriate {@link EndpointAdapter} triggers the 27 * invocation of the endpoint itself. This mechanism can be used for a large field of preprocessing aspects, e.g. for 28 * authorization checks, or message header checks. Its main purpose is to allow for factoring out repetitive endpoint 29 * code. 30 * <p/> 31 * Typically an interceptor chain is defined per {@link EndpointMapping} bean, sharing its granularity. To be able to 32 * apply a certain interceptor chain to a group of handlers, one needs to map the desired handlers via one 33 * <code>EndpointMapping</code> bean. The interceptors themselves are defined as beans in the application context, 34 * referenced by the mapping bean definition via its <code>interceptors</code> property (in XML: a <list> of 35 * <ref>). 36 * 37 * @author Arjen Poutsma 38 * @see EndpointInvocationChain#getInterceptors() 39 * @see org.springframework.ws.server.endpoint.interceptor.EndpointInterceptorAdapter 40 * @see org.springframework.ws.server.endpoint.mapping.AbstractEndpointMapping#setInterceptors(EndpointInterceptor[]) 41 * @since 1.0.0 42 */ 43 public interface EndpointInterceptor { 44 45 /** 46 * Processes the incoming request message. Called after {@link EndpointMapping} determined an appropriate endpoint 47 * object, but before {@link EndpointAdapter} invokes the endpoint. 48 * <p/> 49 * {@link MessageDispatcher} processes an endpoint in an invocation chain, consisting of any number of interceptors, 50 * with the endpoint itself at the end. With this method, each interceptor can decide to abort the chain, typically 51 * creating a custom response. 52 * 53 * @param messageContext contains the incoming request message 54 * @param endpoint chosen endpoint to invoke 55 * @return <code>true</code> to continue processing of the request interceptor chain; <code>false</code> to indicate 56 * blocking of the request endpoint chain, <em>without invoking the endpoint</em> 57 * @throws Exception in case of errors 58 * @see MessageContext#getRequest() 59 */ 60 boolean handleRequest(MessageContext messageContext, Object endpoint) throws Exception; 61 62 /** 63 * Processes the outgoing response message. Called after {@link EndpointAdapter} actually invoked the endpoint. Can 64 * manipulate the response, if any, by adding new headers, etc. 65 * <p/> 66 * {@link MessageDispatcher} processes an endpoint in an invocation chain, consisting of any number of interceptors, 67 * with the endpoint itself at the end. With this method, each interceptor can post-process an invocation, getting 68 * applied in inverse order of the execution chain. 69 * <p/> 70 * Note: Will only be called if this interceptor's {@link #handleRequest} method has successfully completed. 71 * 72 * @param messageContext contains both request and response messages 73 * @param endpoint chosen endpoint to invoke 74 * @return <code>true</code> to continue processing of the reponse interceptor chain; <code>false</code> to indicate 75 * blocking of the response endpoint chain. 76 * @throws Exception in case of errors 77 * @see MessageContext#getRequest() 78 * @see MessageContext#hasResponse() 79 * @see MessageContext#getResponse() 80 */ 81 boolean handleResponse(MessageContext messageContext, Object endpoint) throws Exception; 82 83 /** 84 * Processes the outgoing response fault. Called after {@link EndpointAdapter} actually invoked the endpoint. Can 85 * manipulate the response, if any, by adding new headers, etc. 86 * <p/> 87 * {@link MessageDispatcher} processes an endpoint in an invocation chain, consisting of any number of interceptors, 88 * with the endpoint itself at the end. With this method, each interceptor can post-process an invocation, getting 89 * applied in inverse order of the execution chain. 90 * <p/> 91 * Note: Will only be called if this interceptor's {@link #handleRequest} method has successfully completed. 92 * 93 * @param messageContext contains both request and response messages, the response should contains a Fault 94 * @param endpoint chosen endpoint to invoke 95 * @return <code>true</code> to continue processing of the reponse interceptor chain; <code>false</code> to indicate 96 * blocking of the response handler chain. 97 */ 98 boolean handleFault(MessageContext messageContext, Object endpoint) throws Exception; 99 }