Java tutorial
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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.impl.conn; import java.io.Closeable; import java.io.IOException; import java.net.InetSocketAddress; import java.util.Date; import java.util.concurrent.TimeUnit; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.http.HttpClientConnection; import org.apache.http.HttpHost; import org.apache.http.annotation.GuardedBy; import org.apache.http.annotation.ThreadSafe; import org.apache.http.config.ConnectionConfig; import org.apache.http.config.Lookup; import org.apache.http.config.Registry; import org.apache.http.config.RegistryBuilder; import org.apache.http.config.SocketConfig; import org.apache.http.conn.ConnectionRequest; import org.apache.http.conn.DnsResolver; import org.apache.http.conn.HttpClientConnectionManager; import org.apache.http.conn.HttpConnectionFactory; import org.apache.http.conn.SchemePortResolver; import org.apache.http.conn.ManagedHttpClientConnection; import org.apache.http.conn.routing.HttpRoute; import org.apache.http.conn.socket.ConnectionSocketFactory; import org.apache.http.conn.socket.PlainConnectionSocketFactory; import org.apache.http.conn.ssl.SSLConnectionSocketFactory; import org.apache.http.protocol.HttpContext; import org.apache.http.util.Args; import org.apache.http.util.Asserts; import org.apache.http.util.LangUtils; /** * A connection manager for a single connection. This connection manager maintains only one active * connection. Even though this class is fully thread-safe it ought to be used by one execution * thread only, as only one thread a time can lease the connection at a time. * <p/> * This connection manager will make an effort to reuse the connection for subsequent requests * with the same {@link HttpRoute route}. It will, however, close the existing connection and * open it for the given route, if the route of the persistent connection does not match that * of the connection request. If the connection has been already been allocated * {@link IllegalStateException} is thrown. * <p/> * This connection manager implementation should be used inside an EJB container instead of * {@link PoolingHttpClientConnectionManager}. * * @since 4.3 */ @ThreadSafe public class BasicHttpClientConnectionManager implements HttpClientConnectionManager, Closeable { private final Log log = LogFactory.getLog(getClass()); private final HttpClientConnectionOperator connectionOperator; private final HttpConnectionFactory<HttpRoute, ManagedHttpClientConnection> connFactory; @GuardedBy("this") private ManagedHttpClientConnection conn; @GuardedBy("this") private HttpRoute route; @GuardedBy("this") private Object state; @GuardedBy("this") private long updated; @GuardedBy("this") private long expiry; @GuardedBy("this") private boolean leased; @GuardedBy("this") private SocketConfig socketConfig; @GuardedBy("this") private ConnectionConfig connConfig; @GuardedBy("this") private volatile boolean shutdown; private static Registry<ConnectionSocketFactory> getDefaultRegistry() { return RegistryBuilder.<ConnectionSocketFactory>create() .register("http", PlainConnectionSocketFactory.getSocketFactory()) .register("https", SSLConnectionSocketFactory.getSocketFactory()).build(); } public BasicHttpClientConnectionManager(final Lookup<ConnectionSocketFactory> socketFactoryRegistry, final HttpConnectionFactory<HttpRoute, ManagedHttpClientConnection> connFactory, final SchemePortResolver schemePortResolver, final DnsResolver dnsResolver) { super(); this.connectionOperator = new HttpClientConnectionOperator(socketFactoryRegistry, schemePortResolver, dnsResolver); this.connFactory = connFactory != null ? connFactory : ManagedHttpClientConnectionFactory.INSTANCE; this.expiry = Long.MAX_VALUE; this.socketConfig = SocketConfig.DEFAULT; this.connConfig = ConnectionConfig.DEFAULT; } public BasicHttpClientConnectionManager(final Lookup<ConnectionSocketFactory> socketFactoryRegistry, final HttpConnectionFactory<HttpRoute, ManagedHttpClientConnection> connFactory) { this(socketFactoryRegistry, connFactory, null, null); } public BasicHttpClientConnectionManager(final Lookup<ConnectionSocketFactory> socketFactoryRegistry) { this(socketFactoryRegistry, null, null, null); } public BasicHttpClientConnectionManager() { this(getDefaultRegistry(), null, null, null); } @Override protected void finalize() throws Throwable { try { shutdown(); } finally { // Make sure we call overridden method even if shutdown barfs super.finalize(); } } public void close() { shutdown(); } HttpRoute getRoute() { return route; } Object getState() { return state; } public synchronized SocketConfig getSocketConfig() { return socketConfig; } public synchronized void setSocketConfig(final SocketConfig socketConfig) { this.socketConfig = socketConfig != null ? socketConfig : SocketConfig.DEFAULT; } public synchronized ConnectionConfig getConnectionConfig() { return connConfig; } public synchronized void setConnectionConfig(final ConnectionConfig connConfig) { this.connConfig = connConfig != null ? connConfig : ConnectionConfig.DEFAULT; } public final ConnectionRequest requestConnection(final HttpRoute route, final Object state) { Args.notNull(route, "Route"); return new ConnectionRequest() { public boolean cancel() { // Nothing to abort, since requests are immediate. return false; } public HttpClientConnection get(final long timeout, final TimeUnit tunit) { return BasicHttpClientConnectionManager.this.getConnection(route, state); } }; } private void closeConnection() { if (this.conn != null) { this.log.debug("Closing connection"); try { this.conn.close(); } catch (final IOException iox) { if (this.log.isDebugEnabled()) { this.log.debug("I/O exception closing connection", iox); } } this.conn = null; } } private void shutdownConnection() { if (this.conn != null) { this.log.debug("Shutting down connection"); try { this.conn.shutdown(); } catch (final IOException iox) { if (this.log.isDebugEnabled()) { this.log.debug("I/O exception shutting down connection", iox); } } this.conn = null; } } private void checkExpiry() { if (this.conn != null && System.currentTimeMillis() >= this.expiry) { if (this.log.isDebugEnabled()) { this.log.debug("Connection expired @ " + new Date(this.expiry)); } closeConnection(); } } synchronized HttpClientConnection getConnection(final HttpRoute route, final Object state) { Asserts.check(!this.shutdown, "Connection manager has been shut down"); if (this.log.isDebugEnabled()) { this.log.debug("Get connection for route " + route); } Asserts.check(!this.leased, "Connection is still allocated"); if (!LangUtils.equals(this.route, route) || !LangUtils.equals(this.state, state)) { closeConnection(); } this.route = route; this.state = state; checkExpiry(); if (this.conn == null) { this.conn = this.connFactory.create(route, this.connConfig); } this.leased = true; return this.conn; } public synchronized void releaseConnection(final HttpClientConnection conn, final Object state, final long keepalive, final TimeUnit tunit) { Args.notNull(conn, "Connection"); Asserts.check(conn == this.conn, "Connection not obtained from this manager"); if (this.log.isDebugEnabled()) { this.log.debug("Releasing connection " + conn); } if (this.shutdown) { shutdownConnection(); return; } try { this.updated = System.currentTimeMillis(); if (!this.conn.isOpen()) { this.conn = null; this.route = null; this.conn = null; this.expiry = Long.MAX_VALUE; } else { this.state = state; if (this.log.isDebugEnabled()) { final String s; if (keepalive > 0) { s = "for " + keepalive + " " + tunit; } else { s = "indefinitely"; } this.log.debug("Connection can be kept alive " + s); } if (keepalive > 0) { this.expiry = this.updated + tunit.toMillis(keepalive); } else { this.expiry = Long.MAX_VALUE; } } } finally { this.leased = false; } } public void connect(final HttpClientConnection conn, final HttpRoute route, final int connectTimeout, final HttpContext context) throws IOException { Args.notNull(conn, "Connection"); Args.notNull(route, "HTTP route"); Asserts.check(conn == this.conn, "Connection not obtained from this manager"); final HttpHost host; if (route.getProxyHost() != null) { host = route.getProxyHost(); } else { host = route.getTargetHost(); } final InetSocketAddress localAddress = route.getLocalSocketAddress(); this.connectionOperator.connect(this.conn, host, localAddress, connectTimeout, this.socketConfig, context); } public void upgrade(final HttpClientConnection conn, final HttpRoute route, final HttpContext context) throws IOException { Args.notNull(conn, "Connection"); Args.notNull(route, "HTTP route"); Asserts.check(conn == this.conn, "Connection not obtained from this manager"); this.connectionOperator.upgrade(this.conn, route.getTargetHost(), context); } public void routeComplete(final HttpClientConnection conn, final HttpRoute route, final HttpContext context) throws IOException { } public synchronized void closeExpiredConnections() { if (this.shutdown) { return; } if (!this.leased) { checkExpiry(); } } public synchronized void closeIdleConnections(final long idletime, final TimeUnit tunit) { Args.notNull(tunit, "Time unit"); if (this.shutdown) { return; } if (!this.leased) { long time = tunit.toMillis(idletime); if (time < 0) { time = 0; } final long deadline = System.currentTimeMillis() - time; if (this.updated <= deadline) { closeConnection(); } } } public synchronized void shutdown() { if (this.shutdown) { return; } this.shutdown = true; shutdownConnection(); } }