MySQL helper class for Java. MySQL JDBC driver connection Java class example.

DBHelper.java

/*
Assuming that you have proper MySQL JDBC driver:

How to use this class?
1. Create new object
  DBHelper db = new DBHelper();
2. Open connection
  db.open();
3. Call corresponding method
  db.test();
4. Close connection
  db.close;
  
+ jdbc driver can be found at: http://www.java2s.com/Code/Jar/c/Downloadcommysqljdbc515jar.htm
*/

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * @author nabid
 */
public class DBHelper {
    // JDBC driver name and database URL
    private final String JDBC_DRIVER = "com.mysql.jdbc.Driver";  
    private final String DB_URL = "jdbc:mysql://localhost/database_name";
    
    //  Database credentials
    private static final String USER = "username";
    private static final String PASS = "password";
    
    private Connection conn = null;
    private Statement stmt = null;
    
    public DBHelper() {
        //STEP 2: Register JDBC driver
        try {
            Class.forName(JDBC_DRIVER);
        } catch(Exception e) {
            e.printStackTrace();
        }
    }
    
    public void open() {
        try {
            //System.out.println("Connecting to database...");
            conn = DriverManager.getConnection(DB_URL, USER,PASS);
            //System.out.println("Creating statement...");
            stmt = conn.createStatement();
        } catch (SQLException ex) {
            Logger.getLogger(DBHelper.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
    
    public void close() {
        try {
            stmt.close();
            conn.close();
        } catch (SQLException ex) {
            Logger.getLogger(DBHelper.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
    
    public void test() {
        try {
            String sql;
            sql = "SELECT * FROM table_name";
            ResultSet rs = stmt.executeQuery(sql); // DML
            // stmt.executeUpdate(sql); // DDL
            
            //STEP 5: Extract data from result set
            while(rs.next()){
                //Display values
                System.out.print(rs.getString(1));
                System.out.print(rs.getString(2));
            }
            //STEP 6: Clean-up environment
            rs.close();
        } catch (SQLException ex) {
            Logger.getLogger(DBHelper.class.getName()).log(Level.SEVERE, null, ex);
        }
    }
}

Tanks brooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo

Thanks, buddy.
It's great.

Thank you! I think need replace:
Class.forName("JDBC_DRIVER");
to
Class.forName(JDBC_DRIVER);

Thanks, updated.