http://hc.apache.org/httpcomponents-core-ga: Apache HttpComponents Core (non-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.nio.protocol;

import java.io.Closeable;
import java.io.IOException;

import org.apache.http.HttpException;
import org.apache.http.HttpRequest;
import org.apache.http.nio.ContentDecoder;
import org.apache.http.nio.IOControl;
import org.apache.http.protocol.HttpContext;


HttpAsyncRequestConsumer is a callback interface whose methods get invoked to process an HTTP request message and to stream message content from a non-blocking HTTP connection on the server side. 
Type parameters:
  • <T> – the result type of request processing.
Since:4.2
/**
 * {@code HttpAsyncRequestConsumer} is a callback interface whose methods
 * get invoked to process an HTTP request message and to stream message
 * content from a non-blocking HTTP connection on the server side.
 *
 * @param <T> the result type of request processing.
 * @since 4.2
 */
public interface HttpAsyncRequestConsumer<T> extends Closeable {

    
Invoked when a HTTP request message is received. Please note that the consumeContent(ContentDecoder, IOControl) method will be invoked only for if the request message implements HttpEntityEnclosingRequest interface and has a content entity enclosed. 
Params:
  • request – HTTP request message.
Throws:
/**
     * Invoked when a HTTP request message is received. Please note
     * that the {@link #consumeContent(ContentDecoder, IOControl)} method
     * will be invoked only for if the request message implements
     * {@link org.apache.http.HttpEntityEnclosingRequest} interface and
     * has a content entity enclosed.
     *
     * @param request HTTP request message.
     * @throws HttpException in case of HTTP protocol violation
     * @throws IOException in case of an I/O error
     */
    void requestReceived(HttpRequest request) throws HttpException, IOException;

    
Invoked to process a chunk of content from the ContentDecoder. The IOControl interface can be used to suspend input event notifications if the consumer is temporarily unable to process content. 
 The consumer can use the ContentDecoder.isCompleted() method to find out whether or not the message content has been fully consumed. 
 Please note that the ContentDecoder object is not thread-safe and should only be used within the context of this method call. The IOControl object can be shared and used on other thread to resume input event notifications when the consumer is capable of processing more content. 
Params:
  • decoder – content decoder.
  • ioControl – I/O control of the underlying connection.
Throws:
/**
     * Invoked to process a chunk of content from the {@link ContentDecoder}.
     * The {@link IOControl} interface can be used to suspend input event
     * notifications if the consumer is temporarily unable to process content.
     * <p>
     * The consumer can use the {@link ContentDecoder#isCompleted()} method
     * to find out whether or not the message content has been fully consumed.
     * <p>
     * Please note that the {@link ContentDecoder} object is not thread-safe and
     * should only be used within the context of this method call.
     * The {@link IOControl} object can be shared and used on other thread
     * to resume input event notifications when the consumer is capable of
     * processing more content.
     *
     * @param decoder content decoder.
     * @param ioControl I/O control of the underlying connection.
     * @throws IOException in case of an I/O error
     */
    void consumeContent(ContentDecoder decoder, IOControl ioControl) throws IOException;

    
Invoked to signal that the request has been fully processed.

Params:
  • context – HTTP context
/**
     * Invoked to signal that the request has been fully processed.
     *
     * @param context HTTP context
     */
    void requestCompleted(HttpContext context);

    
Invoked to signal that the request processing terminated abnormally.

Params:
  • ex – exception
/**
     * Invoked to signal that the request processing terminated abnormally.
     *
     * @param ex exception
     */
    void failed(Exception ex);

    
Returns an exception in case of an abnormal termination. This method returns null if the request execution is still ongoing or if it completed successfully. 
See Also:
/**
     * Returns an exception in case of an abnormal termination. This method
     * returns {@code null} if the request execution is still ongoing
     * or if it completed successfully.
     *
     * @see #isDone()
     */
    Exception getException();

    
Returns a result of the request execution, when available. This method returns null if the request execution is still ongoing. 
See Also:
/**
     * Returns a result of the request execution, when available. This method
     * returns {@code null} if the request execution is still ongoing.
     *
     * @see #isDone()
     */
    T getResult();

    
Determines whether or not the request execution completed. If the request processing terminated normally getResult() can be used to obtain the result. If the request processing terminated abnormally getException() can be used to obtain the cause. 
/**
     * Determines whether or not the request execution completed. If the
     * request processing terminated normally {@link #getResult()}
     * can be used to obtain the result. If the request processing terminated
     * abnormally {@link #getException()} can be used to obtain the cause.
     */
    boolean isDone();

}