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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 * 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
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 * 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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package org.apache.http.nio.protocol;

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

import org.apache.http.HttpException;
import org.apache.http.HttpResponse;
import org.apache.http.concurrent.Cancellable;
import org.apache.http.nio.ContentDecoder;
import org.apache.http.nio.IOControl;
import org.apache.http.protocol.HttpContext;


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

    
Invoked when a HTTP response message is received. Please note that the consumeContent(ContentDecoder, IOControl) method will be invoked only if the response messages has a content entity enclosed. 
Params:
  • response – HTTP response message.
Throws:
/**
     * Invoked when a HTTP response message is received. Please note
     * that the {@link #consumeContent(ContentDecoder, IOControl)} method
     * will be invoked only if the response messages has a content entity
     * enclosed.
     *
     * @param response HTTP response message.
     * @throws HttpException in case of HTTP protocol violation
     * @throws IOException in case of an I/O error
     */
    void responseReceived(HttpResponse response) throws IOException, HttpException;

    
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 response has been fully processed.

Params:
  • context – HTTP context
/**
     * Invoked to signal that the response has been fully processed.
     *
     * @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);

    
Returns an exception in case of an abnormal termination. This method returns null if the response processing 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 response processing is still ongoing
     * or if it completed successfully.
     *
     * @see #isDone()
     */
    Exception getException();

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

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

}