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 
/*
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 * Licensed to the Apache Software Foundation (ASF) under one
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 * 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
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 * Unless required by applicable law or agreed to in writing,
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 * under the License.
 * ====================================================================
 *
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package org.apache.http.nio.protocol;

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

import org.apache.http.HttpResponse;
import org.apache.http.nio.ContentEncoder;
import org.apache.http.nio.IOControl;
import org.apache.http.protocol.HttpContext;


HttpAsyncResponseProducer is a callback interface whose methods get invoked to generate an HTTP response message and to stream message content to a non-blocking HTTP connection on the server side. 
Since:4.2
/**
 * {@code HttpAsyncResponseProducer} is a callback interface whose methods
 * get invoked to generate an HTTP response message and to stream message
 * content to a non-blocking HTTP connection on the server side.
 *
 * @since 4.2
 */
public interface HttpAsyncResponseProducer extends Closeable {

    
Invoked to generate a HTTP response message head.

Returns:HTTP response message.
/**
     * Invoked to generate a HTTP response message head.
     *
     * @return HTTP response message.
     */
    HttpResponse generateResponse();

    
Invoked to write out a chunk of content to the ContentEncoder. The IOControl interface can be used to suspend output event notifications if the producer is temporarily unable to produce more content. 

When all content is finished, the producer MUST call ContentEncoder.complete(). Failure to do so may cause the entity to be incorrectly delimited. 
 Please note that the ContentEncoder 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 output event notifications when more content is made available. 
Params:
  • encoder – content encoder.
  • ioControl – I/O control of the underlying connection.
Throws:
/**
     * Invoked to write out a chunk of content to the {@link ContentEncoder}.
     * The {@link IOControl} interface can be used to suspend output event
     * notifications if the producer is temporarily unable to produce more content.
     * <p>
     * When all content is finished, the producer <b>MUST</b> call
     * {@link ContentEncoder#complete()}. Failure to do so may cause the entity
     * to be incorrectly delimited.
     * <p>
     * Please note that the {@link ContentEncoder} 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 output event notifications when more content is made available.
     *
     * @param encoder content encoder.
     * @param ioControl I/O control of the underlying connection.
     * @throws IOException in case of an I/O error
     */
    void produceContent(ContentEncoder encoder, IOControl ioControl) throws IOException;

    
Invoked to signal that the response has been fully written out.

Params:
  • context – HTTP context
/**
     * Invoked to signal that the response has been fully written out.
     *
     * @param context HTTP context
     */
    void responseCompleted(HttpContext context);

    
Invoked to signal that the response processing terminated abnormally.

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

}