http://hc.apache.org/httpcomponents-core-ga: Apache HttpComponents Core (blocking I/O) (The Apache Software Foundation)
  • Julius Davies
  • Andrea Selva
  • Steffen Pingel
  • Quintin Beukes
  • Marc Beyerle
  • James Abley
  • Michajlo Matijkiw 
/*
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.http;

import java.io.IOException;

import org.apache.http.protocol.HttpContext;


HTTP protocol interceptor is a routine that implements a specific aspect of
the HTTP protocol. Usually protocol interceptors are expected to act upon
one specific header or a group of related headers of the incoming message
or populate the outgoing message with one specific header or a group of
related headers.


 Protocol Interceptors can also manipulate content entities enclosed with messages.
Usually this is accomplished by using the 'Decorator' pattern where a wrapper
entity class is used to decorate the original entity.


Protocol interceptors must be implemented as thread-safe. Similarly to
servlets, protocol interceptors should not use instance variables unless
access to those variables is synchronized.

Since:4.0
/**
 * HTTP protocol interceptor is a routine that implements a specific aspect of
 * the HTTP protocol. Usually protocol interceptors are expected to act upon
 * one specific header or a group of related headers of the incoming message
 * or populate the outgoing message with one specific header or a group of
 * related headers.
 * <p>
 *  Protocol Interceptors can also manipulate content entities enclosed with messages.
 * Usually this is accomplished by using the 'Decorator' pattern where a wrapper
 * entity class is used to decorate the original entity.
 * <p>
 * Protocol interceptors must be implemented as thread-safe. Similarly to
 * servlets, protocol interceptors should not use instance variables unless
 * access to those variables is synchronized.
 *
 * @since 4.0
 */
public interface HttpRequestInterceptor {

    
Processes a request.
On the client side, this step is performed before the request is
sent to the server. On the server side, this step is performed
on incoming messages before the message body is evaluated.

Params:
  • request –   the request to preprocess
  • context –   the context for the request
Throws:
/**
     * Processes a request.
     * On the client side, this step is performed before the request is
     * sent to the server. On the server side, this step is performed
     * on incoming messages before the message body is evaluated.
     *
     * @param request   the request to preprocess
     * @param context   the context for the request
     *
     * @throws HttpException in case of an HTTP protocol violation
     * @throws IOException in case of an I/O error
     */
    void process(HttpRequest request, HttpContext context)
        throws HttpException, IOException;

}