Java tutorial
/* * ==================================================================== * 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 * <http://www.apache.org/>. * */ package org.apache.http.nio.conn; import java.io.IOException; import java.util.concurrent.Future; import java.util.concurrent.TimeUnit; import org.apache.http.concurrent.FutureCallback; import org.apache.http.conn.routing.HttpRoute; import org.apache.http.nio.NHttpClientConnection; import org.apache.http.nio.reactor.IOEventDispatch; import org.apache.http.protocol.HttpContext; /** * Represents a manager of persistent client connections. * <p> * The purpose of an HTTP connection manager is to serve as a factory for new * HTTP connections, manage persistent connections and synchronize access to * persistent connections making sure that only one thread of execution can * have access to a connection at a time. * <p> * Implementations of this interface must be thread-safe. Access to shared * data must be synchronized as methods of this interface may be executed * from multiple threads. * * @since 4.0 */ public interface NHttpClientConnectionManager { /** * Returns a {@link Future} for a {@link NHttpClientConnection}. * <p> * Please note that the consumer of that connection is responsible * for fully establishing the route the to the connection target * by calling {@link #startRoute(org.apache.http.nio.NHttpClientConnection, * org.apache.http.conn.routing.HttpRoute, * org.apache.http.protocol.HttpContext) startRoute} in order to start * the process of connection initialization, optionally calling * {@link #upgrade(org.apache.http.nio.NHttpClientConnection, * org.apache.http.conn.routing.HttpRoute, * org.apache.http.protocol.HttpContext) upgrade} method to upgrade * the connection after having executed {@code CONNECT} method to * all intermediate proxy hops and and finally calling * {@link #routeComplete(org.apache.http.nio.NHttpClientConnection, * org.apache.http.conn.routing.HttpRoute, * org.apache.http.protocol.HttpContext) routeComplete} to mark the route * as fully completed. * * @param route HTTP route of the requested connection. * @param state expected state of the connection or {@code null} * if the connection is not expected to carry any state. * @param connectTimeout connect timeout. * @param connectionRequestTimeout connection request timeout. * @param timeUnit time unit of the previous two timeout values. * @param callback future callback. */ Future<NHttpClientConnection> requestConnection(HttpRoute route, Object state, long connectTimeout, long connectionRequestTimeout, TimeUnit timeUnit, FutureCallback<NHttpClientConnection> callback); /** * Releases the connection back to the manager making it potentially * re-usable by other consumers. Optionally, the maximum period * of how long the manager should keep the connection alive can be * defined using {@code validDuration} and {@code timeUnit} * parameters. * * @param conn the managed connection to release. * @param validDuration the duration of time this connection is valid for reuse. * @param timeUnit the time unit. * * @see #closeExpiredConnections() */ void releaseConnection(NHttpClientConnection conn, Object newState, long validDuration, TimeUnit timeUnit); /** * Starts the process of connection initialization. Connection route may consist of several * intermediate hops and may require a protocol upgrade. Once the route is fully established * the {@link #routeComplete(org.apache.http.nio.NHttpClientConnection, * org.apache.http.conn.routing.HttpRoute, * org.apache.http.protocol.HttpContext) routeComplete} method must be called. * * @param conn the managed connection to initialize. * @param route the connection route. * @param context the context */ void startRoute(NHttpClientConnection conn, HttpRoute route, HttpContext context) throws IOException; /** * Upgrades the underlying connection I/O session to TLS/SSL (or another layering * protocol) after having executed {@code CONNECT} method to all * intermediate proxy hops. * * @param conn the managed connection to upgrade. * @param route the connection route. * @param context the context */ void upgrade(NHttpClientConnection conn, HttpRoute route, HttpContext context) throws IOException; /** * Marks the connection as fully established with all its intermediate * hops completed. * * @param conn the managed connection to mark as route complete. * @param route the connection route. * @param context the context */ void routeComplete(NHttpClientConnection conn, HttpRoute route, HttpContext context); /** * Determines if the given connection has been fully established and * marked as route complete. * * @param conn the managed connection. */ boolean isRouteComplete(NHttpClientConnection conn); /** * Closes idle connections in the pool. * <p> * Open connections in the pool that have not been used for the * timespan given by the argument will be closed. * Currently allocated connections are not subject to this method. * Times will be checked with milliseconds precision * * All expired connections will also be closed. * * @param idletime the idle time of connections to be closed * @param tunit the unit for the {@code idletime} * * @see #closeExpiredConnections() */ void closeIdleConnections(long idletime, TimeUnit tunit); /** * Closes all expired connections in the pool. * <p> * Open connections in the pool that have not been used for * the timespan defined when the connection was released will be closed. * Currently allocated connections are not subject to this method. * Times will be checked with milliseconds precision. */ void closeExpiredConnections(); /** * Starts the underlying I/O reactor and initiates the dispatch of * I/O event notifications to the given {@link IOEventDispatch}. */ void execute(IOEventDispatch eventDispatch) throws IOException; /** * Shuts down this connection manager and releases allocated resources. * This includes closing all connections, whether they are currently * used or not. */ void shutdown() throws IOException; }