Use a pool of SAXReaders. JM-364

git-svn-id: http://svn.igniterealtime.org/svn/repos/messenger/trunk@1759 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/messenger/PrivateStorage.java

@@ -11,19 +11,22 @@
 
 package org.jivesoftware.messenger;
 
-import org.jivesoftware.messenger.container.BasicModule;
-import org.jivesoftware.database.DbConnectionManager;
-import org.jivesoftware.util.Log;
-import org.jivesoftware.util.LocaleUtils;
-import org.jivesoftware.util.JiveGlobals;
-import org.dom4j.Element;
 import org.dom4j.Document;
+import org.dom4j.Element;
 import org.dom4j.io.SAXReader;
+import org.jivesoftware.database.DbConnectionManager;
+import org.jivesoftware.messenger.container.BasicModule;
+import org.jivesoftware.util.JiveGlobals;
+import org.jivesoftware.util.LocaleUtils;
+import org.jivesoftware.util.Log;
 
-import java.sql.*;
-import java.sql.Connection;
-import java.io.StringWriter;
 import java.io.StringReader;
+import java.io.StringWriter;
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingQueue;
 
 /**
  * Private storage for user accounts (JEP-0049). It is used by some XMPP systems
@@ -47,7 +50,10 @@ public class PrivateStorage extends BasicModule {
 
     private boolean enabled = JiveGlobals.getBooleanProperty("xmpp.privateStorageEnabled", true);
 
-    SAXReader xmlReader = new SAXReader();
+    /**
+     * Pool of SAX Readers. SAXReader is not thread safe so we need to have a pool of readers.
+     */
+    private BlockingQueue<SAXReader> xmlReaders = new LinkedBlockingQueue<SAXReader>();
 
     /**
      * Constructs a new PrivateStore instance.
@@ -143,7 +149,10 @@ public class PrivateStorage extends BasicModule {
         if (enabled) {
             Connection con = null;
             PreparedStatement pstmt = null;
+            SAXReader xmlReader = null;
             try {
+                // Get a sax reader from the pool
+                xmlReader = xmlReaders.take();
                 con = DbConnectionManager.getConnection();
                 pstmt = con.prepareStatement(LOAD_PRIVATE);
                 pstmt.setString(1, username);
@@ -161,6 +170,8 @@ public class PrivateStorage extends BasicModule {
                 Log.error(LocaleUtils.getLocalizedString("admin.error"), e);
             }
             finally {
+                // Return the sax reader to the pool
+                if (xmlReader != null) xmlReaders.add(xmlReader);
                 try { if (pstmt != null) { pstmt.close(); } }
                 catch (Exception e) { Log.error(e); }
                 try { if (con != null) { con.close(); } }
@@ -169,4 +180,18 @@ public class PrivateStorage extends BasicModule {
         }
         return data;
     }
+
+    public void start() throws IllegalStateException {
+        super.start();
+        // Initialize the pool of sax readers
+        for (int i=0; i<10; i++) {
+            xmlReaders.add(new SAXReader());
+        }
+    }
+
+    public void stop() {
+        super.stop();
+        // Clean up the pool of sax readers
+        xmlReaders.clear();
+    }
 }
\ No newline at end of file

src/java/org/jivesoftware/messenger/vcard/DefaultVCardProvider.java

@@ -14,15 +14,17 @@ package org.jivesoftware.messenger.vcard;
 import org.dom4j.Element;
 import org.dom4j.io.SAXReader;
 import org.jivesoftware.database.DbConnectionManager;
-import org.jivesoftware.util.Log;
 import org.jivesoftware.util.AlreadyExistsException;
+import org.jivesoftware.util.Log;
 import org.jivesoftware.util.NotFoundException;
 
+import java.io.StringReader;
+import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
-import java.sql.Connection;
 import java.sql.SQLException;
-import java.io.StringReader;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingQueue;
 
 /**
  * Default implementation of the VCardProvider interface, which reads and writes data
@@ -41,28 +43,46 @@ public class DefaultVCardProvider implements VCardProvider {
     private static final String INSERT_PROPERTY =
         "INSERT INTO jiveVCard (username, value) VALUES (?, ?)";
 
-    private SAXReader saxReader = new SAXReader();
+    /**
+     * Pool of SAX Readers. SAXReader is not thread safe so we need to have a pool of readers.
+     */
+    private BlockingQueue<SAXReader> xmlReaders = new LinkedBlockingQueue<SAXReader>();
 
 
+    public DefaultVCardProvider() {
+        super();
+        // Initialize the pool of sax readers
+        for (int i=0; i<10; i++) {
+            xmlReaders.add(new SAXReader());
+        }
+    }
+
     public Element loadVCard(String username) {
         synchronized (username.intern()) {
             Element vCardElement = null;
             java.sql.Connection con = null;
             PreparedStatement pstmt = null;
+            SAXReader xmlReader = null;
             try {
+                // Get a sax reader from the pool
+                xmlReader = xmlReaders.take();
                 con = DbConnectionManager.getConnection();
                 pstmt = con.prepareStatement(LOAD_PROPERTIES);
                 pstmt.setString(1, username);
                 ResultSet rs = pstmt.executeQuery();
                 while (rs.next()) {
                     vCardElement =
-                            saxReader.read(new StringReader(rs.getString(1))).getRootElement();
+                            xmlReader.read(new StringReader(rs.getString(1))).getRootElement();
                 }
             }
             catch (Exception e) {
                 Log.error(e);
             }
             finally {
+                // Return the sax reader to the pool
+                if (xmlReader != null) {
+                    xmlReaders.add(xmlReader);
+                }
                 try { if (pstmt != null) { pstmt.close(); } }
                 catch (Exception e) { Log.error(e); }
                 try { if (con != null) { con.close(); } }