michael@0: /*
michael@0:  * ====================================================================
michael@0:  * Licensed to the Apache Software Foundation (ASF) under one
michael@0:  * or more contributor license agreements.  See the NOTICE file
michael@0:  * distributed with this work for additional information
michael@0:  * regarding copyright ownership.  The ASF licenses this file
michael@0:  * to you under the Apache License, Version 2.0 (the
michael@0:  * "License"); you may not use this file except in compliance
michael@0:  * with the License.  You may obtain a copy of the License at
michael@0:  *
michael@0:  *   http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing,
michael@0:  * software distributed under the License is distributed on an
michael@0:  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
michael@0:  * KIND, either express or implied.  See the License for the
michael@0:  * specific language governing permissions and limitations
michael@0:  * under the License.
michael@0:  * ====================================================================
michael@0:  *
michael@0:  * This software consists of voluntary contributions made by many
michael@0:  * individuals on behalf of the Apache Software Foundation.  For more
michael@0:  * information on the Apache Software Foundation, please see
michael@0:  * <http://www.apache.org/>.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: package ch.boye.httpclientandroidlib;
michael@0: 
michael@0: import java.io.IOException;
michael@0: 
michael@0: /**
michael@0:  * A generic HTTP connection, useful on client and server side.
michael@0:  *
michael@0:  * @since 4.0
michael@0:  */
michael@0: public interface HttpConnection {
michael@0: 
michael@0:     /**
michael@0:      * Closes this connection gracefully.
michael@0:      * This method will attempt to flush the internal output
michael@0:      * buffer prior to closing the underlying socket.
michael@0:      * This method MUST NOT be called from a different thread to force
michael@0:      * shutdown of the connection. Use {@link #shutdown shutdown} instead.
michael@0:      */
michael@0:     public void close() throws IOException;
michael@0: 
michael@0:     /**
michael@0:      * Checks if this connection is open.
michael@0:      * @return true if it is open, false if it is closed.
michael@0:      */
michael@0:     public boolean isOpen();
michael@0: 
michael@0:     /**
michael@0:      * Checks whether this connection has gone down.
michael@0:      * Network connections may get closed during some time of inactivity
michael@0:      * for several reasons. The next time a read is attempted on such a
michael@0:      * connection it will throw an IOException.
michael@0:      * This method tries to alleviate this inconvenience by trying to
michael@0:      * find out if a connection is still usable. Implementations may do
michael@0:      * that by attempting a read with a very small timeout. Thus this
michael@0:      * method may block for a small amount of time before returning a result.
michael@0:      * It is therefore an <i>expensive</i> operation.
michael@0:      *
michael@0:      * @return  <code>true</code> if attempts to use this connection are
michael@0:      *          likely to succeed, or <code>false</code> if they are likely
michael@0:      *          to fail and this connection should be closed
michael@0:      */
michael@0:     public boolean isStale();
michael@0: 
michael@0:     /**
michael@0:      * Sets the socket timeout value.
michael@0:      *
michael@0:      * @param timeout timeout value in milliseconds
michael@0:      */
michael@0:     void setSocketTimeout(int timeout);
michael@0: 
michael@0:     /**
michael@0:      * Returns the socket timeout value.
michael@0:      *
michael@0:      * @return positive value in milliseconds if a timeout is set,
michael@0:      * <code>0</code> if timeout is disabled or <code>-1</code> if
michael@0:      * timeout is undefined.
michael@0:      */
michael@0:     int getSocketTimeout();
michael@0: 
michael@0:     /**
michael@0:      * Force-closes this connection.
michael@0:      * This is the only method of a connection which may be called
michael@0:      * from a different thread to terminate the connection.
michael@0:      * This method will not attempt to flush the transmitter's
michael@0:      * internal buffer prior to closing the underlying socket.
michael@0:      */
michael@0:     public void shutdown() throws IOException;
michael@0: 
michael@0:     /**
michael@0:      * Returns a collection of connection metrics.
michael@0:      *
michael@0:      * @return HttpConnectionMetrics
michael@0:      */
michael@0:     HttpConnectionMetrics getMetrics();
michael@0: 
michael@0: }