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 * KIND, either express or implied.  See the License for the
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package org.apache.http.nio;

import java.io.IOException;

import org.apache.http.HttpException;

Abstract server-side HTTP event handler.
Since:
4.2/**
 * Abstract server-side HTTP event handler.
 *
 * @since 4.2
 */
public interface NHttpServerEventHandler {

    
Triggered when a new incoming connection is created.
Params:
conn – new incoming connection HTTP connection./**
     * Triggered when a new incoming connection is created.
     *
     * @param conn new incoming connection HTTP connection.
     */
    void connected(
            NHttpServerConnection conn) throws IOException, HttpException;

    
Triggered when a new HTTP request is received. The connection
passed as a parameter to this method is guaranteed to return
a valid HTTP request object.
 If the request received encloses a request entity this method will be followed a series of inputReady(NHttpServerConnection, ContentDecoder) calls to transfer the request content. 
Params:
conn – HTTP connection that contains a new HTTP request
See Also:
NHttpServerConnection/**
     * Triggered when a new HTTP request is received. The connection
     * passed as a parameter to this method is guaranteed to return
     * a valid HTTP request object.
     * <p>
     * If the request received encloses a request entity this method will
     * be followed a series of
     * {@link #inputReady(NHttpServerConnection, ContentDecoder)} calls
     * to transfer the request content.
     *
     * @see NHttpServerConnection
     *
     * @param conn HTTP connection that contains a new HTTP request
     */
    void requestReceived(
            NHttpServerConnection conn) throws IOException, HttpException;

    
Triggered when the underlying channel is ready for reading a
new portion of the request entity through the corresponding
content decoder.
 If the content consumer is unable to process incoming content, input event notifications can be temporarily suspended using IOControl interface (super interface of NHttpServerConnection). 
 Please note that the NHttpServerConnection and ContentDecoder objects are 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 handler is capable of processing more content. 
Params:
conn – HTTP connection that can produce a new portion of the
incoming request content.
decoder – The content decoder to use to read content.
See Also:
NHttpServerConnection
ContentDecoder
IOControl/**
     * Triggered when the underlying channel is ready for reading a
     * new portion of the request entity through the corresponding
     * content decoder.
     * <p>
     * If the content consumer is unable to process incoming content,
     * input event notifications can be temporarily suspended using
     * {@link IOControl} interface (super interface of {@link NHttpServerConnection}).
     * <p>
     * Please note that the {@link NHttpServerConnection} and {@link ContentDecoder}
     * objects are 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 handler is capable of
     * processing more content.
     *
     * @see NHttpServerConnection
     * @see ContentDecoder
     * @see IOControl
     *
     * @param conn HTTP connection that can produce a new portion of the
     * incoming request content.
     * @param decoder The content decoder to use to read content.
     */
    void inputReady(
            NHttpServerConnection conn,
            ContentDecoder decoder) throws IOException, HttpException;

    
Triggered when the connection is ready to accept a new HTTP response.
The protocol handler does not have to submit a response if it is not
ready.
Params:
conn – HTTP connection that contains an HTTP response
See Also:
NHttpServerConnection/**
     * Triggered when the connection is ready to accept a new HTTP response.
     * The protocol handler does not have to submit a response if it is not
     * ready.
     *
     * @see NHttpServerConnection
     *
     * @param conn HTTP connection that contains an HTTP response
     */
    void responseReady(
            NHttpServerConnection conn) throws IOException, HttpException;

    
Triggered when the underlying channel is ready for writing a
next portion of the response entity through the corresponding
content encoder.
 If the content producer is unable to generate outgoing content, output event notifications can be temporarily suspended using IOControl interface (super interface of NHttpServerConnection). 
 Please note that the NHttpServerConnection and ContentEncoder objects are 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:
conn – HTTP connection that can accommodate a new portion
of the outgoing response content.
encoder – The content encoder to use to write content.
See Also:
NHttpServerConnection
ContentEncoder
IOControl/**
     * Triggered when the underlying channel is ready for writing a
     * next portion of the response entity through the corresponding
     * content encoder.
     * <p>
     * If the content producer is unable to generate outgoing content,
     * output event notifications can be temporarily suspended using
     * {@link IOControl} interface (super interface of {@link NHttpServerConnection}).
     * <p>
     * Please note that the {@link NHttpServerConnection} and {@link ContentEncoder}
     * objects are 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.
     *
     * @see NHttpServerConnection
     * @see ContentEncoder
     * @see IOControl
     *
     * @param conn HTTP connection that can accommodate a new portion
     * of the outgoing response content.
     * @param encoder The content encoder to use to write content.
     */
    void outputReady(
            NHttpServerConnection conn,
            ContentEncoder encoder) throws IOException, HttpException;

    
Triggered when the connection is closed by the opposite end point
(half-closed).
Params:
conn – half-closed HTTP connection./**
     * Triggered when the connection is closed by the opposite end point
     * (half-closed).
     *
     * @param conn half-closed HTTP connection.
     */
    void endOfInput(
            NHttpServerConnection conn) throws IOException;

    
Triggered when no input is detected on this connection over the
maximum period of inactivity.
Params:
conn – HTTP connection that caused timeout condition./**
     * Triggered when no input is detected on this connection over the
     * maximum period of inactivity.
     *
     * @param conn HTTP connection that caused timeout condition.
     */
    void timeout(
            NHttpServerConnection conn) throws IOException;

    
Triggered when the connection is closed.
Params:
conn – closed HTTP connection./**
     * Triggered when the connection is closed.
     *
     * @param conn closed HTTP connection.
     */
    void closed(NHttpServerConnection conn);

    
Triggered if an error occurs during the HTTP exchange.
Params:
conn – HTTP connection that caused an I/O error
ex – exception/**
     * Triggered if an error occurs during the HTTP exchange.
     *
     * @param conn HTTP connection that caused an I/O error
     * @param ex exception
     */
    void exception(NHttpServerConnection conn, Exception ex);

}