Use PoolingHttpClientConnectionManager to handle postback persistent connections

to Portal.

src/main/java/altk/comm/engine/CommEngine.java

@@ -5,6 +5,9 @@ import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.io.PrintWriter;
+import java.security.KeyManagementException;
+import java.security.KeyStoreException;
+import java.security.NoSuchAlgorithmException;
 import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.Map;
@@ -587,15 +590,19 @@ public abstract class CommEngine extends HttpServlet
      */
     abstract protected void destroyChild();
 
-    public PostBack getPostBack(String postBackURL, String broadcastType)
+    public PostBack getPostBack(String postBackURL, String broadcastType) throws BroadcastException
     {
         if (postBackURL == null) return null;
 
         PostBack postBack = postBackMap.get(postBackURL);
         if (postBack != null) return postBack;
         
-        postBack = new PostBack(postBackURL, broadcastType + "_status",
-                postbackMaxQueueSize, postbackSenderPoolSize, postbackMaxBatchSize);
+        try {
+			postBack = new PostBack(postBackURL, broadcastType + "_status",
+			        postbackMaxQueueSize, postbackSenderPoolSize, postbackMaxBatchSize);
+		} catch (KeyManagementException | IllegalArgumentException | NoSuchAlgorithmException | KeyStoreException e) {
+			throw new BroadcastException(BroadcastError.PLATFORM_ERROR, e.getMessage(), e);
+		}
         postBackMap.put(postBackURL, postBack);
         return postBack;
     }

src/main/java/altk/comm/engine/postback/PostBack.java

@@ -21,6 +21,7 @@ import javax.xml.xpath.XPathExpressionException;
 import javax.xml.xpath.XPathFactory;
 
 import org.apache.http.StatusLine;
+import org.apache.http.client.HttpRequestRetryHandler;
 import org.apache.http.client.methods.CloseableHttpResponse;
 import org.apache.http.client.methods.HttpPost;
 import org.apache.http.conn.ssl.NoopHostnameVerifier;
@@ -29,7 +30,9 @@ import org.apache.http.conn.ssl.TrustStrategy;
 import org.apache.http.entity.StringEntity;
 import org.apache.http.impl.client.CloseableHttpClient;
 import org.apache.http.impl.client.HttpClientBuilder;
+import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
 import org.apache.http.protocol.BasicHttpContext;
+import org.apache.http.protocol.HttpContext;
 import org.apache.http.ssl.SSLContextBuilder;
 import org.apache.http.util.EntityUtils;
 import org.apache.log4j.Logger;
@@ -57,6 +60,8 @@ public class PostBack
     
     private static final int QUEUE_WAIT = 300; // seconds
     private static final int POSTBACK_SERVER_WAIT_TIME = 10; // seconds
+
+	private static final int RETRIES_DEFAULT = 3;
     
     private final String postBackURL;
     private final String xmlTopElement;
@@ -66,7 +71,16 @@ public class PostBack
     private final String myName;
     private int maxBatchSize;
 
+    private PoolingHttpClientConnectionManager cm;
     private int threadsWaitingToPost;
+	private TrustStrategy tustAllCerts;
+    SSLContext sslContext;
+    SSLConnectionSocketFactory connectionFactory;
+    CloseableHttpClient httpclient;
+
+	private int maxRetries;  
+
+
 
     private static Logger myLogger = Logger.getLogger(PostBack.class);
 
@@ -82,6 +96,7 @@ public class PostBack
     {
         private boolean threadShouldStop;
 
+
         private Sender(String name)
         {
             setName(name);
@@ -192,16 +207,12 @@ public class PostBack
             }
             xml.append("</"); xml.append(xmlTopElement); xml.append(">");
             
-            TrustStrategy tustAllCerts = new TrustStrategy() { public boolean isTrusted(X509Certificate[] chain, String authType) { return true; } };
             HttpPost httpPost = new HttpPost(postBackURL);
             StringEntity requestEntity;
             CloseableHttpResponse response = null;
             byte[] xmlBytes = null;
             try
             {
-                SSLContext sslContext = SSLContextBuilder.create().loadTrustMaterial(tustAllCerts).build();
-                SSLConnectionSocketFactory connectionFactory = new SSLConnectionSocketFactory(sslContext, new NoopHostnameVerifier());
-                CloseableHttpClient httpclient = HttpClientBuilder.create().setSSLSocketFactory(connectionFactory).build();
                 requestEntity = (new StringEntity(xml.toString()));
                 httpPost.setEntity(requestEntity);
                 myLogger.debug("Posting to " + postBackURL + ": " + xml);
@@ -224,11 +235,7 @@ public class PostBack
                 CommonLogger.alarm.error("While posting back to broadcast requester: " + e);
                 return PostBackStatus.IRRECOVERABLE_ERROR;
             }
-            catch (KeyManagementException | NoSuchAlgorithmException  | KeyStoreException e)
-            {
-                CommonLogger.alarm.error("Totally unexpected.  While constructing HttpClient for posting back to broadcast requester: " + e);
-                return PostBackStatus.IRRECOVERABLE_ERROR;
-            }
+          
 
             String xmlStr;
             try
@@ -317,10 +324,13 @@ public class PostBack
      * @param xmlTopElementName
      * @throws IllegalArgumentException if either postBackURL or xmlTopElementName is
      *         not supplied nor valid.
+     * @throws KeyStoreException 
+     * @throws NoSuchAlgorithmException 
+     * @throws KeyManagementException 
      */
     public PostBack(String postBackURL, String xmlTopElementName,
             int maxQueueSize, int senderPoolSize, int maxBatchSize)
-    throws IllegalArgumentException
+    throws IllegalArgumentException, KeyManagementException, NoSuchAlgorithmException, KeyStoreException
     {
         if (postBackURL == null || postBackURL.length() == 0)
         {
@@ -337,7 +347,36 @@ public class PostBack
         this.maxBatchSize = maxBatchSize;
         postQueue = new LinkedList<String>();
         threadsWaitingToPost = 0;
+        cm = new PoolingHttpClientConnectionManager();
+        cm.setMaxTotal(senderPoolSize);
+        cm.setDefaultMaxPerRoute(senderPoolSize);
+        
+    	tustAllCerts = new TrustStrategy() { public boolean isTrusted(X509Certificate[] chain, String authType) { return true; } };
+    	
+    	sslContext = SSLContextBuilder.create().loadTrustMaterial(tustAllCerts).build();
+        connectionFactory = new SSLConnectionSocketFactory(sslContext, new NoopHostnameVerifier());
         
+        //
+        // Retry handler
+        maxRetries = RETRIES_DEFAULT;
+        HttpRequestRetryHandler retryHandler = new HttpRequestRetryHandler()
+        {
+            public boolean retryRequest(
+                    IOException exception,
+                    int executionCount,
+                    HttpContext context)
+            {
+                if (executionCount >= maxRetries) return false;
+                return true;
+            }
+        };
+
+        httpclient = HttpClientBuilder.create()
+ //       		.setConnectionManager(cm)
+ //       		.setRetryHandler(retryHandler)
+        		.setSSLSocketFactory(connectionFactory)
+        		.build();
+
         senderPool = new ArrayList<Sender>();
         for (int i = 0; i < senderPoolSize; i++)
         {
@@ -393,6 +432,16 @@ public class PostBack
 
     public void terminate()
     {
+    	try 
+    	{
+			httpclient.close();
+		} 
+    	catch (IOException e) 
+    	{
+			myLogger.error("Caught when closing HttpClient: " + e.getMessage());
+		}
+    	
+    	// Terminate postback threads
         for (Sender sender : senderPool)
         {
             sender.terminate();