* Cleaned up expired / idle connection eviction code

* Added sample of expired / idle connection eviction
* Cleaned up examples 


git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@749322 13f79535-47bb-0310-9956-ffa450edef68

httpclient/src/examples/org/apache/http/examples/client/ClientAbortMethod.java

@@ -61,6 +61,11 @@ public class ClientAbortMethod {
         // Do not feel like reading the response body
         // Call abort on the request object
         httpget.abort();
+        
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 
 }

httpclient/src/examples/org/apache/http/examples/client/ClientAuthentication.java

@@ -65,5 +65,10 @@ public class ClientAuthentication {
         if (entity != null) {
             entity.consumeContent();
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 }

httpclient/src/examples/org/apache/http/examples/client/ClientChunkEncodedPost.java

@@ -81,6 +81,11 @@ public class ClientChunkEncodedPost {
         if (resEntity != null) {
             resEntity.consumeContent();
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
     
 }

httpclient/src/examples/org/apache/http/examples/client/ClientConnectionRelease.java

@@ -94,6 +94,11 @@ public class ClientConnectionRelease {
                 
             }
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 
 }

httpclient/src/examples/org/apache/http/examples/client/ClientCustomContext.java

@@ -86,6 +86,11 @@ public class ClientCustomContext {
         entity.consumeContent();
         
         System.out.println("----------------------------------------");
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
     
 }

httpclient/src/examples/org/apache/http/examples/client/ClientCustomSSL.java

@@ -76,6 +76,11 @@ public class ClientCustomSSL {
         if (entity != null) {
             entity.consumeContent();
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 
 }

httpclient/src/examples/org/apache/http/examples/client/ClientEvictExpiredConnections.java

@@ -0,0 +1,154 @@
+/*
+ * $HeadURL:$
+ * $Revision:$
+ * $Date:$
+ *
+ * ====================================================================
+ *
+ *  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.examples.client;
+
+import java.util.concurrent.TimeUnit;
+
+import org.apache.http.HttpEntity;
+import org.apache.http.HttpResponse;
+import org.apache.http.HttpVersion;
+import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
+import org.apache.http.conn.ClientConnectionManager;
+import org.apache.http.conn.params.ConnManagerParams;
+import org.apache.http.conn.scheme.PlainSocketFactory;
+import org.apache.http.conn.scheme.Scheme;
+import org.apache.http.conn.scheme.SchemeRegistry;
+import org.apache.http.impl.client.DefaultHttpClient;
+import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
+import org.apache.http.params.BasicHttpParams;
+import org.apache.http.params.HttpParams;
+import org.apache.http.params.HttpProtocolParams;
+
+/**
+ * Example demonstrating how to evict expired and idle connections
+ * from the connection pool.
+ */
+public class ClientEvictExpiredConnections {
+
+    public static void main(String[] args) throws Exception {
+        // Create and initialize HTTP parameters
+        HttpParams params = new BasicHttpParams();
+        ConnManagerParams.setMaxTotalConnections(params, 100);
+        HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);
+        
+        // Create and initialize scheme registry 
+        SchemeRegistry schemeRegistry = new SchemeRegistry();
+        schemeRegistry.register(
+                new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
+        
+        ClientConnectionManager cm = new ThreadSafeClientConnManager(params, schemeRegistry);
+        HttpClient httpclient = new DefaultHttpClient(cm, params);
+        
+        // create an array of URIs to perform GETs on
+        String[] urisToGet = {
+            "http://jakarta.apache.org/",
+            "http://jakarta.apache.org/commons/",
+            "http://jakarta.apache.org/commons/httpclient/",
+            "http://svn.apache.org/viewvc/jakarta/httpcomponents/"
+        };
+        
+        IdleConnectionEvictor connEvictor = new IdleConnectionEvictor(cm);
+        connEvictor.start();
+        
+        for (int i = 0; i < urisToGet.length; i++) {
+            String requestURI = urisToGet[i];
+            HttpGet req = new HttpGet(requestURI);
+
+            System.out.println("executing request " + requestURI);
+
+            HttpResponse rsp = httpclient.execute(req);
+            HttpEntity entity = rsp.getEntity();
+
+            System.out.println("----------------------------------------");
+            System.out.println(rsp.getStatusLine());
+            if (entity != null) {
+                System.out.println("Response content length: " + entity.getContentLength());
+            }
+            System.out.println("----------------------------------------");
+
+            if (entity != null) {
+                entity.consumeContent();
+            }
+        }
+        
+        // Sleep 10 sec and let the connection evictor do its job
+        Thread.sleep(20000);
+        
+        // Shut down the evictor thread
+        connEvictor.shutdown();
+        connEvictor.join();
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
+    }
+    
+    public static class IdleConnectionEvictor extends Thread {
+        
+        private final ClientConnectionManager connMgr;
+        
+        private volatile boolean shutdown;
+        
+        public IdleConnectionEvictor(ClientConnectionManager connMgr) {
+            super();
+            this.connMgr = connMgr;
+        }
+
+        @Override
+        public void run() {
+            try {
+                while (!shutdown) {
+                    synchronized (this) {
+                        wait(5000);
+                        // Close expired connections
+                        connMgr.closeExpiredConnections();
+                        // Optionally, close connections
+                        // that have been idle longer than 5 sec
+                        connMgr.closeIdleConnections(5, TimeUnit.SECONDS);
+                    }
+                }
+            } catch (InterruptedException ex) {
+                // terminate
+            }
+        }
+        
+        public void shutdown() {
+            shutdown = true;
+            synchronized (this) {
+                notifyAll();
+            }
+        }
+        
+    }
+    
+}

httpclient/src/examples/org/apache/http/examples/client/ClientExecuteDirect.java

@@ -34,17 +34,16 @@ package org.apache.http.examples.client;
 import org.apache.http.Header;
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpHost;
-import org.apache.http.HttpRequest;
 import org.apache.http.HttpResponse;
 import org.apache.http.HttpVersion;
 import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
 import org.apache.http.conn.ClientConnectionManager;
 import org.apache.http.conn.scheme.PlainSocketFactory;
 import org.apache.http.conn.scheme.Scheme;
 import org.apache.http.conn.scheme.SchemeRegistry;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
-import org.apache.http.message.BasicHttpRequest;
 import org.apache.http.params.BasicHttpParams;
 import org.apache.http.params.HttpParams;
 import org.apache.http.params.HttpProtocolParams;
@@ -79,7 +78,7 @@ public class ClientExecuteDirect {
                 supportedSchemes);
         DefaultHttpClient httpclient = new DefaultHttpClient(connMgr, params);
 
-        HttpRequest req = new BasicHttpRequest("GET", "/", HttpVersion.HTTP_1_1);
+        HttpGet req = new HttpGet("/");
 
         System.out.println("executing request to " + target);
 
@@ -97,6 +96,11 @@ public class ClientExecuteDirect {
         if (entity != null) {
             System.out.println(EntityUtils.toString(entity));
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 
 }

httpclient/src/examples/org/apache/http/examples/client/ClientExecuteProxy.java

@@ -34,10 +34,10 @@ package org.apache.http.examples.client;
 import org.apache.http.Header;
 import org.apache.http.HttpEntity;
 import org.apache.http.HttpHost;
-import org.apache.http.HttpRequest;
 import org.apache.http.HttpResponse;
 import org.apache.http.HttpVersion;
 import org.apache.http.client.HttpClient;
+import org.apache.http.client.methods.HttpGet;
 import org.apache.http.conn.ClientConnectionManager;
 import org.apache.http.conn.params.ConnRoutePNames;
 import org.apache.http.conn.scheme.PlainSocketFactory;
@@ -46,7 +46,6 @@ import org.apache.http.conn.scheme.SchemeRegistry;
 import org.apache.http.conn.ssl.SSLSocketFactory;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
-import org.apache.http.message.BasicHttpRequest;
 import org.apache.http.params.BasicHttpParams;
 import org.apache.http.params.HttpParams;
 import org.apache.http.params.HttpProtocolParams;
@@ -88,7 +87,7 @@ public class ClientExecuteProxy {
 
         httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
 
-        HttpRequest req = new BasicHttpRequest("GET", "/", HttpVersion.HTTP_1_1);
+        HttpGet req = new HttpGet("/");
 
         System.out.println("executing request to " + target + " via " + proxy);
         HttpResponse rsp = httpclient.execute(target, req);
@@ -105,6 +104,11 @@ public class ClientExecuteProxy {
         if (entity != null) {
             System.out.println(EntityUtils.toString(entity));
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 
 }

httpclient/src/examples/org/apache/http/examples/client/ClientFormLogin.java

@@ -99,5 +99,10 @@ public class ClientFormLogin {
                 System.out.println("- " + cookies.get(i).toString());
             }
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 }

httpclient/src/examples/org/apache/http/examples/client/ClientGZipContentCompression.java

@@ -120,6 +120,11 @@ public class ClientGZipContentCompression {
             System.out.println("----------------------------------------");
             System.out.println("Uncompressed size: "+content.length());
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 
     static class GzipDecompressingEntity extends HttpEntityWrapper {

httpclient/src/examples/org/apache/http/examples/client/ClientInteractiveAuthentication.java

@@ -113,5 +113,10 @@ public class ClientInteractiveAuthentication {
                 trying = false;
             }
         }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 }

httpclient/src/examples/org/apache/http/examples/client/ClientMultiThreadedExecution.java

@@ -40,7 +40,6 @@ import org.apache.http.conn.params.ConnManagerParams;
 import org.apache.http.conn.scheme.PlainSocketFactory;
 import org.apache.http.conn.scheme.Scheme;
 import org.apache.http.conn.scheme.SchemeRegistry;
-import org.apache.http.conn.ssl.SSLSocketFactory;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.apache.http.impl.conn.tsccm.ThreadSafeClientConnManager;
 import org.apache.http.params.BasicHttpParams;
@@ -66,8 +65,6 @@ public class ClientMultiThreadedExecution {
         SchemeRegistry schemeRegistry = new SchemeRegistry();
         schemeRegistry.register(
                 new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));
-        schemeRegistry.register(
-                new Scheme("https", SSLSocketFactory.getSocketFactory(), 443));
         
         // Create an HttpClient with the ThreadSafeClientConnManager.
         // This connection manager must be used if more than one thread will
@@ -77,10 +74,10 @@ public class ClientMultiThreadedExecution {
         
         // create an array of URIs to perform GETs on
         String[] urisToGet = {
-            "http://jakarta.apache.org/",
-            "http://jakarta.apache.org/commons/",
-            "http://jakarta.apache.org/commons/httpclient/",
-            "http://svn.apache.org/viewvc/jakarta/httpcomponents/"
+            "http://hc.apache.org/",
+            "http://hc.apache.org/httpcomponents-core/",
+            "http://hc.apache.org/httpcomponents-client/",
+            "http://svn.apache.org/viewvc/httpcomponents/"
         };
         
         // create a thread for each URI
@@ -95,6 +92,15 @@ public class ClientMultiThreadedExecution {
             threads[j].start();
         }
         
+        // join the threads
+        for (int j = 0; j < threads.length; j++) {
+            threads[j].join();
+        }
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpClient.getConnectionManager().shutdown();        
     }
     
     /**

httpclient/src/examples/org/apache/http/examples/client/ClientPreemptiveBasicAuthentication.java

@@ -98,6 +98,11 @@ public class ClientPreemptiveBasicAuthentication {
                 entity.consumeContent();
             }
         }
+        
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
     
     static class PreemptiveAuth implements HttpRequestInterceptor {

httpclient/src/examples/org/apache/http/examples/client/ClientPreemptiveDigestAuthentication.java

@@ -104,6 +104,11 @@ public class ClientPreemptiveDigestAuthentication {
                 entity.consumeContent();
             }
         }
+        
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
     
     static class PreemptiveAuth implements HttpRequestInterceptor {

httpclient/src/examples/org/apache/http/examples/client/ClientProxyAuthentication.java

@@ -54,8 +54,7 @@ public class ClientProxyAuthentication {
         HttpHost targetHost = new HttpHost("www.verisign.com", 443, "https"); 
         HttpHost proxy = new HttpHost("localhost", 8080); 
 
-        httpclient.getParams().setParameter
-            (ConnRoutePNames.DEFAULT_PROXY, proxy);
+        httpclient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, proxy);
 
         HttpGet httpget = new HttpGet("/");
         
@@ -74,5 +73,10 @@ public class ClientProxyAuthentication {
         if (entity != null) {
             entity.consumeContent();
         }
+        
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
 }

httpclient/src/examples/org/apache/http/examples/client/ClientWithResponseHandler.java

@@ -57,6 +57,11 @@ public class ClientWithResponseHandler {
         System.out.println(responseBody);
         
         System.out.println("----------------------------------------");
+
+        // When HttpClient instance is no longer needed, 
+        // shut down the connection manager to ensure
+        // immediate deallocation of all system resources
+        httpclient.getConnectionManager().shutdown();        
     }
     
 }

httpclient/src/main/java/org/apache/http/impl/conn/IdleConnectionHandler.java

@@ -111,18 +111,15 @@ public class IdleConnectionHandler {
      * 
      * @param idleTime the minimum idle time, in milliseconds, for connections to be closed
      */
-    //@@@ add TimeUnit argument here?
     public void closeIdleConnections(long idleTime) {
         
         // the latest time for which connections will be closed
         long idleTimeout = System.currentTimeMillis() - idleTime;
 
         if (log.isDebugEnabled()) {
-            log.debug("Checking for connections, idleTimeout: "  + idleTimeout);
+            log.debug("Checking for connections, idle timeout: "  + idleTimeout);
         }
-        
-        Iterator<HttpConnection> connectionIter =
-            connectionToTimes.keySet().iterator();
+        Iterator<HttpConnection> connectionIter = connectionToTimes.keySet().iterator();
         
         while (connectionIter.hasNext()) {
             HttpConnection conn = connectionIter.next();
@@ -130,9 +127,8 @@ public class IdleConnectionHandler {
             long connectionTime = times.timeAdded;
             if (connectionTime <= idleTimeout) {
                 if (log.isDebugEnabled()) {
-                    log.debug("Closing connection, connection time: "  + connectionTime);
+                    log.debug("Closing idle connection, connection time: "  + connectionTime);
                 }
-                connectionIter.remove();
                 try {
                     conn.close();
                 } catch (IOException ex) {
@@ -159,7 +155,6 @@ public class IdleConnectionHandler {
                 if (log.isDebugEnabled()) {
                     log.debug("Closing connection, expired @: "  + times.timeExpires);
                 }
-                connectionIter.remove();
                 try {
                     conn.close();
                 } catch (IOException ex) {

httpclient/src/main/java/org/apache/http/impl/conn/tsccm/AbstractConnPool.java

@@ -262,8 +262,6 @@ public abstract class AbstractConnPool implements RefQueueHandler {
     }
 
         
-    //@@@ revise this cleanup stuff (closeIdle+deleteClosed), it's not good
-
     /**
      * Deletes all entries for closed connections.
      */
@@ -325,9 +323,5 @@ public abstract class AbstractConnPool implements RefQueueHandler {
         }
     }
 
-
-
-
-
 } // class AbstractConnPool
 

httpclient/src/main/java/org/apache/http/impl/conn/tsccm/ConnPoolByRoute.java

@@ -638,15 +638,10 @@ public class ConnPoolByRoute extends AbstractConnPool {
     }
 
 
-    //@@@ revise this cleanup stuff
-    //@@@ move method to base class when deleteEntry() is fixed
-    // non-javadoc, see base class AbstractConnPool
     @Override
     public void deleteClosedConnections() {
-
         poolLock.lock();
         try {
-
             Iterator<BasicPoolEntry>  iter = freeConnections.iterator();
             while (iter.hasNext()) {
                 BasicPoolEntry entry = iter.next();
@@ -655,7 +650,6 @@ public class ConnPoolByRoute extends AbstractConnPool {
                     deleteEntry(entry);
                 }
             }
-
         } finally {
             poolLock.unlock();
         }
@@ -677,6 +671,11 @@ public class ConnPoolByRoute extends AbstractConnPool {
             while (ibpe.hasNext()) {
                 BasicPoolEntry entry = ibpe.next();
                 ibpe.remove();
+                
+                if (log.isDebugEnabled()) {
+                    log.debug("Closing connection" 
+                            + " [" + entry.getPlannedRoute() + "][" + entry.getState() + "]");
+                }
                 closeConnection(entry.getConnection());
             }
 

httpclient/src/main/java/org/apache/http/impl/conn/tsccm/RefQueueWorker.java

@@ -33,11 +33,6 @@ package org.apache.http.impl.conn.tsccm;
 import java.lang.ref.Reference;
 import java.lang.ref.ReferenceQueue;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-
-
-
 /**
  * A worker thread for processing queued references.
  * {@link Reference Reference}s can be
@@ -51,8 +46,6 @@ import org.apache.commons.logging.LogFactory;
  */
 public class RefQueueWorker implements Runnable {
 
-    private final Log log = LogFactory.getLog(getClass());
-
     /** The reference queue to monitor. */
     protected final ReferenceQueue<?> refQueue;
 
@@ -103,12 +96,7 @@ public class RefQueueWorker implements Runnable {
                 // remove the next reference and process it
                 Reference<?> ref = refQueue.remove();
                 refHandler.handleReference(ref);
-            } catch (InterruptedException e) {
-                //@@@ is logging really necessary? this here is the
-                //@@@ only reason for having a log in this class
-                if (log.isDebugEnabled()) {
-                    log.debug(this.toString() + " interrupted", e);
-                }
+            } catch (InterruptedException ignore) {
             }
         }
     }

httpclient/src/main/java/org/apache/http/impl/conn/tsccm/ThreadSafeClientConnManager.java

@@ -231,6 +231,7 @@ public class ThreadSafeClientConnManager implements ClientConnectionManager {
 
     // non-javadoc, see interface ClientConnectionManager
     public void shutdown() {
+        log.debug("Shutting down");
         connectionPool.shutdown();
     }
 
@@ -268,12 +269,15 @@ public class ThreadSafeClientConnManager implements ClientConnectionManager {
 
     // non-javadoc, see interface ClientConnectionManager
     public void closeIdleConnections(long idleTimeout, TimeUnit tunit) {
-        // combine these two in a single call?
+        if (log.isDebugEnabled()) {
+            log.debug("Closing connections idle for " + idleTimeout + " " + tunit);
+        }
         connectionPool.closeIdleConnections(idleTimeout, tunit);
         connectionPool.deleteClosedConnections();
     }
     
     public void closeExpiredConnections() {
+        log.debug("Closing expired connections");
         connectionPool.closeExpiredConnections();
         connectionPool.deleteClosedConnections();
     }