Getting Error:closing a connection for you. Please help

[rajikannan]

Hello,
I'm using jboss3.2.6. I used ejb2.1 (session bean and entity bean[BMP]). I did few data base transations in cmp and few in simple data source connection.

I'm getting below errors occasionally
'No managed connection exception
java.lang.OutOfMemoryError: Java heap space
[CachedConnectionManager] Closing a connection for you. Plea
se close them yourself: org.jboss.resource.adapter.jdbc.WrappedConnection@11ed0d
5

I've given below my dao connection code here,

package com.drtrack.util;

import java.sql.Connection;
import java.sql.SQLException;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;

public class DAOUtil {

 private static DataSource _ds;

 public Connection con;
 public DAOUtil() throws SQLException {

 try {

 if (_ds == null)
 assemble();
 if(_ds != null && con == null) {

 con = _ds.getConnection();

 }
 }catch(SQLException ex) {

 ex.printStackTrace();

 }

 }

 private void assemble() {
 Context ic = null;
 try {

 ic = new InitialContext();
 DrTrackUtil drutil = new DrTrackUtil();
 _ds = (DataSource) ic.lookup("java:/" + drutil.getText("SOURCE_DIR"));
 drutil = null;
 }catch (Exception e) {

 e.printStackTrace();

 }finally {
 try {
 ic.close();
 }catch(NamingException ne) {}
 }

 }

 public void closeConnection() throws SQLException {

 if(con != null)
 con.close();

 con = null;
 }

}

below is the code with get connection and doing transaction in it.

 public static AccountMasterValueBean getAccountMasterByAcctId(String acctId) {

 AccountMasterValueBean bean = null;
 DAOUtil dao = null;
 CallableStatement cst = null;
 ResultSet rs = null;
 try {
 dao = new DAOUtil();

 cst = dao.con.prepareCall(DrTrackConstants.MSSQL_USP_ACCOUNTMASTER_BY_ACCTID);
 cst.setObject(1, acctId);

 rs = cst.executeQuery();
 if(rs != null && rs.next()) {

 bean = new AccountMasterValueBean(
 Integer.valueOf(rs.getString("accountkeyid")),
 rs.getString("latitude"),
 rs.getString("longitude"));

 }
 }catch(SQLException se) {
 logger.info("SQL Error: " + se);
 }
 finally {
 if(rs != null){
 try {
 rs.close();
 }catch(SQLException se) {
 logger.info("SQL Error: " + se);
 }
 finally {
 rs = null;
 }
 }
 if(cst != null) {
 try{
 cst.close();
 }catch(SQLException se) {
 logger.info("SQL Error: " + se);
 }
 finally {
 cst = null;
 }
 }
 if(dao != null) {
 try {
 dao.closeConnection();
 }catch(SQLException se) {
 logger.info("SQL Error: " + se);
 }
 finally {
 dao = null;
 }
 }
 }
 return bean;
 }

I closed connections, resultsets and statements properly.
Why I'm getting these errors.? Where I'm doing wrong. ? Please help me. I have to fix them ASAP.

Thanks.