Memory Leakage with Tomcat

Question

Hi,
I have created an application that uses a single JSP and makes multiple calls to a database. It does populate a couple of arrays with values and then uses those values to get other values from the database.
I am noticing through Windows Task Manager that when I initially start Tomcat, the memory goes up to about 36mb. It then continues to grow by about 3mb per user that makes a new connection. It can get up to about 200mb, and then I forced to restart tomcat.
Im sure this is a memory leak issue. Is there any suggestions as to what I should do to get rid of this??
My connections are all closed and released, both database and result sets. I am preforming garbage collection.
I am using sessions, when users log in (dont know whether this has anything to do with it??)
Anyway, any help is greatly appreciated.
Cheers

Answer 1

Thanks for the help guys,
I run a query for the first time I load the site that loads everything into the session. I then chcek that the user is logged in? If the user is logged in, then it loads a instance of that single session.
If not, then it just loads the not logged in session page.
Thanks for that bit of connection architecture ronaldharing.
My connection class is similar, though I will make some modifications to this with your changes in place, and see how it goes.
This is my conncection class im using:
package Vidz;
import java.io.*;
import java.util.*;
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class DBConnection {
     public String status;
     public int vendorStatus;
     public Connection conn;
     public Statement stmt;
     public CallableStatement callStmt;
     public PreparedStatement preparedStmt;
     public ResultSet rset;
     public SQLWarning thisWarning;
     public boolean thisConnClosed;
* Establishes a connection to the database.
public DBConnection() {
try {
          Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
          conn = DriverManager.getConnection ( "jdbc:odbc:databaseName","","" );
     thisWarning = conn.getWarnings();
conn.setAutoCommit(true);
status = "open";
} catch (Exception e) {status="DBConnection construction error:"+e.toString();
* Return java.sql.ResultSet
public synchronized ResultSet executeQuery(String command) {
try {
status=command;
stmt = conn.createStatement ();
status+="*";
rset = stmt.executeQuery(command);
status+="executeQuery OK: "+command;
return rset;
} catch (Exception e) {status=e.toString();return null;}
* Return int indicator to show whether statement successful.
public synchronized int executeUpdate(String command) {
try {
stmt = conn.createStatement ();
status="executeUpdate OK: "+command;
return stmt.executeUpdate(command);
} catch (Exception e) {status=e.toString();return -1;}
public void close() throws java.sql.SQLException
if( conn != null )
if( ! conn.isClosed() )
conn.close();
* On garbage collection, close db connection
protected void finalize() throws IOException
try
if( conn != null )
if( ! conn.isClosed() )
conn.close();
catch (java.sql.SQLException e) {}
Sridharranganathan : I store the result of the query in the session, along with any images etc. I want each user to load just the one page, to improve optimization.
Thanks for all your help people!
Any more suggestions would be much appreciated