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package org.apache.http.nio;

import org.apache.http.HttpConnection;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.protocol.HttpContext;

Abstract non-blocking HTTP connection interface. Each connection contains an HTTP execution context, which can be used to maintain a processing state, as well as the actual HttpRequest and HttpResponse that are being transmitted over this connection. Both the request and the response objects can be null if there is no incoming or outgoing message currently being transferred. 
 Please note non-blocking HTTP connections are stateful and not thread safe. Input / output operations on non-blocking HTTP connections should be restricted to the dispatch events triggered by the I/O event dispatch thread. However, the IOControl interface is fully threading safe and can be manipulated from any thread. 
Since:
4.0/**
 * Abstract non-blocking HTTP connection interface. Each connection contains an
 * HTTP execution context, which can be used to maintain a processing state,
 * as well as the actual {@link HttpRequest} and {@link HttpResponse} that are
 * being transmitted over this connection. Both the request and
 * the response objects can be {@code null} if there is no incoming or
 * outgoing message currently being transferred.
 * <p>
 * Please note non-blocking HTTP connections are stateful and not thread safe.
 * Input / output operations on non-blocking HTTP connections should be
 * restricted to the dispatch events triggered by the I/O event dispatch thread.
 * However, the {@link IOControl} interface is fully threading safe and can be
 * manipulated from any thread.
 *
 * @since 4.0
 */
public interface NHttpConnection extends HttpConnection, IOControl {

    public static final int ACTIVE      = 0;
    public static final int CLOSING     = 1;
    public static final int CLOSED      = 2;

    
Returns status of the connection:
 ACTIVE: connection is active. 
 CLOSING: connection is being closed. 
 CLOSED: connection has been closed. 
Returns:
connection status./**
     * Returns status of the connection:
     * <p>
     * {@link #ACTIVE}: connection is active.
     * <p>
     * {@link #CLOSING}: connection is being closed.
     * <p>
     * {@link #CLOSED}: connection has been closed.
     *
     * @return connection status.
     */
    int getStatus();

    
Returns the current HTTP request if one is being received / transmitted. Otherwise returns null. 
Returns:
HTTP request, if available, null otherwise./**
     * Returns the current HTTP request if one is being received / transmitted.
     * Otherwise returns {@code null}.
     *
     * @return HTTP request, if available, {@code null} otherwise.
     */
    HttpRequest getHttpRequest();

    
Returns the current HTTP response if one is being received / transmitted. Otherwise returns null. 
Returns:
HTTP response, if available, null otherwise./**
     * Returns the current HTTP response if one is being received / transmitted.
     * Otherwise returns {@code null}.
     *
     * @return HTTP response, if available, {@code null} otherwise.
     */
    HttpResponse getHttpResponse();

    
Returns an HTTP execution context associated with this connection.
Returns:
HTTP context/**
     * Returns an HTTP execution context associated with this connection.
     * @return HTTP context
     */
    HttpContext getContext();

}