_Connector.java

package com.uca.dao;

import com.uca.core.*;
import com.uca.dao.*;
import com.uca.entity.*;
import java.util.*;

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

public class _Connector {

    private static String url = "jdbc:h2:~/test";

    private static String user = "sa";

    private static String passwd = "";

    private static Connection connect;

    public static Connection getInstance(){
        if(connect == null){
            try {
                connect = DriverManager.getConnection(url, user, passwd);
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        return connect;
    }


}