/*
    * ====================================================================
    * 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.impl.conn.tsccm;
  
  import java.io.IOException;
  import java.util.concurrent.TimeUnit;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.http.annotation.ThreadSafe;
  import org.apache.http.conn.ClientConnectionManager;
  import org.apache.http.conn.ClientConnectionOperator;
  import org.apache.http.conn.ClientConnectionRequest;
  import org.apache.http.conn.ConnectionPoolTimeoutException;
  import org.apache.http.conn.ManagedClientConnection;
  import org.apache.http.conn.OperatedClientConnection;
  import org.apache.http.conn.params.ConnPerRouteBean;
  import org.apache.http.conn.routing.HttpRoute;
  import org.apache.http.conn.scheme.SchemeRegistry;
  import org.apache.http.impl.conn.DefaultClientConnectionOperator;
  import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
  import org.apache.http.impl.conn.SchemeRegistryFactory;
  import org.apache.http.params.HttpParams;
  import org.apache.http.util.Args;
  import org.apache.http.util.Asserts;
  
  /**
   * Manages a pool of {@link OperatedClientConnection client connections} and
   * is able to service connection requests from multiple execution threads.
   * Connections are pooled on a per route basis. A request for a route which
   * already the manager has persistent connections for available in the pool
   * will be services by leasing a connection from the pool rather than
   * creating a brand new connection.
   * <p>
   * ThreadSafeClientConnManager maintains a maximum limit of connection on
   * a per route basis and in total. Per default this implementation will
   * create no more than than 2 concurrent connections per given route
   * and no more 20 connections in total. For many real-world applications
   * these limits may prove too constraining, especially if they use HTTP
   * as a transport protocol for their services. Connection limits, however,
   * can be adjusted using HTTP parameters.
   *
   * @since 4.0
   *
   * @deprecated (4.2)  use {@link PoolingHttpClientConnectionManager}
   */
  @ThreadSafe
  @Deprecated
  public class ThreadSafeClientConnManager implements ClientConnectionManager {
  
      private final Log log;
  
      /** The schemes supported by this connection manager. */
      protected final SchemeRegistry schemeRegistry; // @ThreadSafe
  
      protected final AbstractConnPool connectionPool;
  
      /** The pool of connections being managed. */
      protected final ConnPoolByRoute pool;
  
      /** The operator for opening and updating connections. */
      protected final ClientConnectionOperator connOperator; // DefaultClientConnectionOperator is @ThreadSafe
  
      protected final ConnPerRouteBean connPerRoute;
  
      /**
       * Creates a new thread safe connection manager.
       *
       * @param schreg    the scheme registry.
       */
      public ThreadSafeClientConnManager(final SchemeRegistry schreg) {
          this(schreg, -1, TimeUnit.MILLISECONDS);
      }
  
      /**
      * @since 4.1
      */
     public ThreadSafeClientConnManager() {
         this(SchemeRegistryFactory.createDefault());
     }
 
     /**
      * Creates a new thread safe connection manager.
      *
      * @param schreg    the scheme registry.
      * @param connTTL   max connection lifetime, <=0 implies "infinity"
      * @param connTTLTimeUnit   TimeUnit of connTTL
      *
      * @since 4.1
      */
     public ThreadSafeClientConnManager(final SchemeRegistry schreg,
             final long connTTL, final TimeUnit connTTLTimeUnit) {
         this(schreg, connTTL, connTTLTimeUnit, new ConnPerRouteBean());
     }
 
     /**
      * Creates a new thread safe connection manager.
      *
      * @param schreg    the scheme registry.
      * @param connTTL   max connection lifetime, <=0 implies "infinity"
      * @param connTTLTimeUnit   TimeUnit of connTTL
      * @param connPerRoute    mapping of maximum connections per route,
      *   provided as a dependency so it can be managed externally, e.g.
      *   for dynamic connection pool size management.
      *
      * @since 4.2
      */
     public ThreadSafeClientConnManager(final SchemeRegistry schreg,
             final long connTTL, final TimeUnit connTTLTimeUnit, final ConnPerRouteBean connPerRoute) {
         super();
         Args.notNull(schreg, "Scheme registry");
         this.log = LogFactory.getLog(getClass());
         this.schemeRegistry = schreg;
         this.connPerRoute = connPerRoute;
         this.connOperator = createConnectionOperator(schreg);
         this.pool = createConnectionPool(connTTL, connTTLTimeUnit) ;
         this.connectionPool = this.pool;
     }
 
     /**
      * Creates a new thread safe connection manager.
      *
      * @param params    the parameters for this manager.
      * @param schreg    the scheme registry.
      *
      * @deprecated (4.1)  use {@link ThreadSafeClientConnManager#ThreadSafeClientConnManager(SchemeRegistry)}
      */
     @Deprecated
     public ThreadSafeClientConnManager(final HttpParams params,
                                        final SchemeRegistry schreg) {
         Args.notNull(schreg, "Scheme registry");
         this.log = LogFactory.getLog(getClass());
         this.schemeRegistry = schreg;
         this.connPerRoute = new ConnPerRouteBean();
         this.connOperator = createConnectionOperator(schreg);
         this.pool = (ConnPoolByRoute) createConnectionPool(params) ;
         this.connectionPool = this.pool;
     }
 
     @Override
     protected void finalize() throws Throwable {
         try {
             shutdown();
         } finally {
             super.finalize();
         }
     }
 
     /**
      * Hook for creating the connection pool.
      *
      * @return  the connection pool to use
      *
      * @deprecated (4.1)  use #createConnectionPool(long, TimeUnit))
      */
     @Deprecated
     protected AbstractConnPool createConnectionPool(final HttpParams params) {
         return new ConnPoolByRoute(connOperator, params);
     }
 
     /**
      * Hook for creating the connection pool.
      *
      * @return  the connection pool to use
      *
      * @since 4.1
      */
     protected ConnPoolByRoute createConnectionPool(final long connTTL, final TimeUnit connTTLTimeUnit) {
         return new ConnPoolByRoute(connOperator, connPerRoute, 20, connTTL, connTTLTimeUnit);
     }
 
     /**
      * Hook for creating the connection operator.
      * It is called by the constructor.
      * Derived classes can override this method to change the
      * instantiation of the operator.
      * The default implementation here instantiates
      * {@link DefaultClientConnectionOperator DefaultClientConnectionOperator}.
      *
      * @param schreg    the scheme registry.
      *
      * @return  the connection operator to use
      */
     protected ClientConnectionOperator
         createConnectionOperator(final SchemeRegistry schreg) {
 
         return new DefaultClientConnectionOperator(schreg);// @ThreadSafe
     }
 
     public SchemeRegistry getSchemeRegistry() {
         return this.schemeRegistry;
     }
 
     public ClientConnectionRequest requestConnection(
             final HttpRoute route,
             final Object state) {
 
         final PoolEntryRequest poolRequest = pool.requestPoolEntry(
                 route, state);
 
         return new ClientConnectionRequest() {
 
             public void abortRequest() {
                 poolRequest.abortRequest();
             }
 
             public ManagedClientConnection getConnection(
                     final long timeout, final TimeUnit tunit) throws InterruptedException,
                     ConnectionPoolTimeoutException {
                 Args.notNull(route, "Route");
 
                 if (log.isDebugEnabled()) {
                     log.debug("Get connection: " + route + ", timeout = " + timeout);
                 }
 
                 final BasicPoolEntry entry = poolRequest.getPoolEntry(timeout, tunit);
                 return new BasicPooledConnAdapter(ThreadSafeClientConnManager.this, entry);
             }
 
         };
 
     }
 
     public void releaseConnection(final ManagedClientConnection conn, final long validDuration, final TimeUnit timeUnit) {
         Args.check(conn instanceof BasicPooledConnAdapter, "Connection class mismatch, " +
                 "connection not obtained from this manager");
         final BasicPooledConnAdapter hca = (BasicPooledConnAdapter) conn;
         if (hca.getPoolEntry() != null) {
             Asserts.check(hca.getManager() == this, "Connection not obtained from this manager");
         }
         synchronized (hca) {
             final BasicPoolEntry entry = (BasicPoolEntry) hca.getPoolEntry();
             if (entry == null) {
                 return;
             }
             try {
                 // make sure that the response has been read completely
                 if (hca.isOpen() && !hca.isMarkedReusable()) {
                     // In MTHCM, there would be a call to
                     // SimpleHttpConnectionManager.finishLastResponse(conn);
                     // Consuming the response is handled outside in 4.0.
 
                     // make sure this connection will not be re-used
                     // Shut down rather than close, we might have gotten here
                     // because of a shutdown trigger.
                     // Shutdown of the adapter also clears the tracked route.
                     hca.shutdown();
                 }
             } catch (final IOException iox) {
                 if (log.isDebugEnabled()) {
                     log.debug("Exception shutting down released connection.",
                               iox);
                 }
             } finally {
                 final boolean reusable = hca.isMarkedReusable();
                 if (log.isDebugEnabled()) {
                     if (reusable) {
                         log.debug("Released connection is reusable.");
                     } else {
                         log.debug("Released connection is not reusable.");
                     }
                 }
                 hca.detach();
                 pool.freeEntry(entry, reusable, validDuration, timeUnit);
             }
         }
     }
 
     public void shutdown() {
         log.debug("Shutting down");
         pool.shutdown();
     }
 
     /**
      * Gets the total number of pooled connections for the given route.
      * This is the total number of connections that have been created and
      * are still in use by this connection manager for the route.
      * This value will not exceed the maximum number of connections per host.
      *
      * @param route     the route in question
      *
      * @return  the total number of pooled connections for that route
      */
     public int getConnectionsInPool(final HttpRoute route) {
         return pool.getConnectionsInPool(route);
     }
 
     /**
      * Gets the total number of pooled connections.  This is the total number of
      * connections that have been created and are still in use by this connection
      * manager.  This value will not exceed the maximum number of connections
      * in total.
      *
      * @return the total number of pooled connections
      */
     public int getConnectionsInPool() {
         return pool.getConnectionsInPool();
     }
 
     public void closeIdleConnections(final long idleTimeout, final TimeUnit tunit) {
         if (log.isDebugEnabled()) {
             log.debug("Closing connections idle longer than " + idleTimeout + " " + tunit);
         }
         pool.closeIdleConnections(idleTimeout, tunit);
     }
 
     public void closeExpiredConnections() {
         log.debug("Closing expired connections");
         pool.closeExpiredConnections();
     }
 
     /**
      * since 4.1
      */
     public int getMaxTotal() {
         return pool.getMaxTotalConnections();
     }
 
     /**
      * since 4.1
      */
     public void setMaxTotal(final int max) {
         pool.setMaxTotalConnections(max);
     }
 
     /**
      * @since 4.1
      */
     public int getDefaultMaxPerRoute() {
         return connPerRoute.getDefaultMaxPerRoute();
     }
 
     /**
      * @since 4.1
      */
     public void setDefaultMaxPerRoute(final int max) {
         connPerRoute.setDefaultMaxPerRoute(max);
     }
 
     /**
      * @since 4.1
      */
     public int getMaxForRoute(final HttpRoute route) {
         return connPerRoute.getMaxForRoute(route);
     }
 
     /**
      * @since 4.1
      */
     public void setMaxForRoute(final HttpRoute route, final int max) {
         connPerRoute.setMaxForRoute(route, max);
     }
 
 }