org.apache.http.HttpConnection Maven / Gradle / Ivy
/*
* ====================================================================
* 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
* .
*
*/
package org.apache.http;
import java.io.Closeable;
import java.io.IOException;
/**
* A generic HTTP connection, useful on client and server side.
*
* @since 4.0
*/
public interface HttpConnection extends Closeable {
/**
* Closes this connection gracefully.
* This method will attempt to flush the internal output
* buffer prior to closing the underlying socket.
* This method MUST NOT be called from a different thread to force
* shutdown of the connection. Use {@link #shutdown shutdown} instead.
*/
@Override
void close() throws IOException;
/**
* Checks if this connection is open.
* @return true if it is open, false if it is closed.
*/
boolean isOpen();
/**
* Checks whether this connection has gone down.
* Network connections may get closed during some time of inactivity
* for several reasons. The next time a read is attempted on such a
* connection it will throw an IOException.
* This method tries to alleviate this inconvenience by trying to
* find out if a connection is still usable. Implementations may do
* that by attempting a read with a very small timeout. Thus this
* method may block for a small amount of time before returning a result.
* It is therefore an expensive operation.
*
* @return {@code true} if attempts to use this connection are
* likely to succeed, or {@code false} if they are likely
* to fail and this connection should be closed
*/
boolean isStale();
/**
* Sets the socket timeout value.
*
* @param timeout timeout value in milliseconds
*/
void setSocketTimeout(int timeout);
/**
* Returns the socket timeout value.
*
* @return positive value in milliseconds if a timeout is set,
* {@code 0} if timeout is disabled or {@code -1} if
* timeout is undefined.
*/
int getSocketTimeout();
/**
* Force-closes this connection.
* This is the only method of a connection which may be called
* from a different thread to terminate the connection.
* This method will not attempt to flush the transmitter's
* internal buffer prior to closing the underlying socket.
*/
void shutdown() throws IOException;
/**
* Returns a collection of connection metrics.
*
* @return HttpConnectionMetrics
*/
HttpConnectionMetrics getMetrics();
}