Struts 2 --java.lang.NullPointerException

[Vic Hood]

Hi,
Im developing a simple struts2 application where im required to insert /update a row into a database . However when i try doing the same it throws a nullpointer exception The code snippet for the same from the action class and the dao class are below.Please help in solving the problem.

Action class..

public String addupDomain(){// Class used to insert a value or execute an update query based on object id from domain table.(Logic in  DAO class)
		String result= SUCCESS;	
		System.out.println("Inside AddDomain");
		if(listbean!=null){
			try {System.out.println("Inside add try");
				if(DomainDAO.addupDomain(listbean)){
					result= SUCCESS;
					System.out.println("Adding a tuple");
				}
				
					else {System.out.println("Bean");
						result=ERROR;
					}
				}
			catch (Exception e) {
				System.out.println("Inside add catch");
				result= null;
				listbean=null;
				System.out.println("Adddomain isnt working.");
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	
		listDomain(dt_oid);
		return result;
	}

DAO class--

public static boolean addupDomain(DomainBean listbean) throws Exception {
		Connection con = null;
		PreparedStatement stmt = null;
		ResultSet rs = null;
;
		boolean output=false;
		int result = 0;
		try {
			con= DBConnector.getConnection();
			if (con != null){
				System.out.println("Connected");
				
				if (listbean.getObjid()!=null){
					System.out.println("Update");
					
					String query1=" UPDATE DOMAIN SET objectid='"+listbean.getObjid()+"',isactive='"+listbean.getActive()+"',code='"+listbean.getCode()+"',description='"+listbean.getDescription()+"',iseditable='"+listbean.getEdit()+"',domaintype_oid="+ listbean.getDt_oid()+"  WHERE objectid='"+listbean.getObjid()+"'";
					stmt = con.prepareStatement(query1);
					int i = stmt.executeUpdate();
					


					if (i >= 1) {
					
						System.out.println("Updation  Done");
						output= true;
					}

					
					
				}
				
				else{
						System.out.println("In ");
						String query= "INSERT INTO DOMAIN (OBJECTID,ISACTIVE,CODE,DESCRIPTION,ISEDITABLE,DOMAINTYPE_OID) VALUES (?,?,?,?,?,?)" ;
						stmt = con.prepareStatement(query);
						stmt.setInt(1,++result);
						System.out.println("OBJECTID"+ listbean.getObjid());
						stmt.setBoolean(2, (listbean.getActive()));
						stmt.setString(3, listbean.getCode());
						stmt.setString(4, listbean.getDescription());
						stmt.setBoolean(5, (listbean.getEdit()));
						stmt.setInt(6,listbean.getDt_oid());
						stmt.executeUpdate();
						output= true;
				}
				
			}

		} catch (SQLException sqe) {
			sqe.printStackTrace();

		} finally {
			DBConnector.closeResultSet(rs);
			DBConnector.closeStatement(stmt);
			DBConnector.closeConnection(con);
			
			return output;
		}
	
	}