| /* |
| * 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. |
| */ |
| |
| package libcore.net.http; |
| |
| import dalvik.system.SocketTagger; |
| import java.io.IOException; |
| import java.net.Socket; |
| import java.net.SocketException; |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.List; |
| |
| /** |
| * A pool of HTTP connections. This class exposes its tuning parameters as |
| * system properties: |
| * <ul> |
| * <li>{@code http.keepAlive} true if HTTP connections should be pooled at |
| * all. Default is true. |
| * <li>{@code http.maxConnections} maximum number of connections to each URI. |
| * Default is 5. |
| * </ul> |
| * |
| * <p>This class <i>doesn't</i> adjust its configuration as system properties |
| * are changed. This assumes that the applications that set these parameters do |
| * so before making HTTP connections, and that this class is initialized lazily. |
| */ |
| final class HttpConnectionPool { |
| |
| public static final HttpConnectionPool INSTANCE = new HttpConnectionPool(); |
| |
| private final int maxConnections; |
| private final HashMap<HttpConnection.Address, List<HttpConnection>> connectionPool |
| = new HashMap<HttpConnection.Address, List<HttpConnection>>(); |
| |
| private HttpConnectionPool() { |
| String keepAlive = System.getProperty("http.keepAlive"); |
| if (keepAlive != null && !Boolean.parseBoolean(keepAlive)) { |
| maxConnections = 0; |
| return; |
| } |
| |
| String maxConnectionsString = System.getProperty("http.maxConnections"); |
| this.maxConnections = maxConnectionsString != null |
| ? Integer.parseInt(maxConnectionsString) |
| : 5; |
| } |
| |
| public HttpConnection get(HttpConnection.Address address, int connectTimeout) |
| throws IOException { |
| // First try to reuse an existing HTTP connection. |
| synchronized (connectionPool) { |
| List<HttpConnection> connections = connectionPool.get(address); |
| while (connections != null) { |
| HttpConnection connection = connections.remove(connections.size() - 1); |
| if (connections.isEmpty()) { |
| connectionPool.remove(address); |
| connections = null; |
| } |
| if (connection.isEligibleForRecycling()) { |
| // Since Socket is recycled, re-tag before using |
| Socket socket = connection.getSocket(); |
| SocketTagger.get().tag(socket); |
| return connection; |
| } |
| } |
| } |
| |
| /* |
| * We couldn't find a reusable connection, so we need to create a new |
| * connection. We're careful not to do so while holding a lock! |
| */ |
| return address.connect(connectTimeout); |
| } |
| |
| public void recycle(HttpConnection connection) { |
| Socket socket = connection.getSocket(); |
| try { |
| SocketTagger.get().untag(socket); |
| } catch (SocketException e) { |
| // When unable to remove tagging, skip recycling and close |
| System.logW("Unable to untagSocket(): " + e); |
| connection.closeSocketAndStreams(); |
| return; |
| } |
| |
| if (maxConnections > 0 && connection.isEligibleForRecycling()) { |
| HttpConnection.Address address = connection.getAddress(); |
| synchronized (connectionPool) { |
| List<HttpConnection> connections = connectionPool.get(address); |
| if (connections == null) { |
| connections = new ArrayList<HttpConnection>(); |
| connectionPool.put(address, connections); |
| } |
| if (connections.size() < maxConnections) { |
| connection.setRecycled(); |
| connections.add(connection); |
| return; // keep the connection open |
| } |
| } |
| } |
| |
| // don't close streams while holding a lock! |
| connection.closeSocketAndStreams(); |
| } |
| } |