Post 2 - Conexão

package com.gmail.dougpts.dao;

import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.rowset.CachedRowSet;
import com.sun.rowset.CachedRowSetImpl;
import java.sql.Connection;

public class Conexao {

   //Coloque aqui o drive de conexão com o banco de dados
   private static String DRIVER = "com.mysql.jdbc.Driver";
   //Coloque aqui a URL do banco junto com seu nome
   private static String URL = "jdbc:mysql://localhost/teste?zeroDateTimeBehavior=convertToNull";
   //Coloque aqui o usuário do Banco de Dados
   private static String USUARIO = "root";
   //Coloque aqui a senha do Banco de Dados
   private static String SENHA = "root";

   public static Connection openConnection() {
       try {
           Class.forName(DRIVER);
           Connection conn = DriverManager.getConnection(URL, USUARIO, SENHA);
           return conn;
       } catch (SQLException ex) {
           print(ex.getMessage());
       } catch (ClassNotFoundException e) {
           e.printStackTrace();
       }
       return null;
   }

   public static void closeConnection(Connection con){
       try {
           con.close();
       } catch (SQLException ex) {
           print(ex.getMessage());
       }
   }

   public static void insert(String table, String atributos, String valores){
       try {
           Connection con = openConnection();
           PreparedStatement stm;
           String sql = "INSERT INTO " + table + " (" + atributos + ") VALUES (" + valores + ");";
           stm = con.prepareStatement(sql);
           stm.executeUpdate();
           closeConnection(con);
       } catch (SQLException ex) {
           print(ex.getMessage());
       }
   }

   public static void update(String table, String pk, String id, String campos){
       try {
           Connection con = openConnection();
           PreparedStatement stm;
           String sql = "UPDATE " + table + " SET " + campos + " WHERE " + pk + " = '" + id + "'";
           stm = con.prepareStatement(sql);
           stm.executeUpdate();
           closeConnection(con);
       } catch (SQLException ex) {
           print(ex.getMessage());
       }

   }

   public static void delete(String table, String condicoes){
       try {
           Connection con = openConnection();
           String sql = "DELETE FROM " + table + " WHERE " + condicoes;
           PreparedStatement stm = con.prepareStatement(sql);
           stm.executeUpdate();
           closeConnection(con);
       } catch (SQLException ex) {
           print(ex.getMessage());
       }
   }

   public static boolean isExist(String tabela, String nomeColuna, String where){
       try {
           String query = "SELECT COUNT(" + nomeColuna + ") AS CONT  FROM " + tabela + " WHERE  " + where;
           CachedRowSet result = Conexao.getRowSet(query);
           if (result.next()) {
               int cont = Integer.parseInt(result.getString("CONT"));
               if (cont > 0) {
                   return true;
               }
           }
       } catch (SQLException ex) {
           print(ex.getMessage());
       }
       return false;
   }

   public static CachedRowSet getRowSet(String sql){
       try {
           Connection con = openConnection();
           PreparedStatement stm = con.prepareStatement(sql);
           ResultSet rs = stm.executeQuery();
           CachedRowSet result = new CachedRowSetImpl();
           result.populate(rs);
           rs.close();
           closeConnection(con);
           return result;
       } catch (SQLException ex) {
           print(ex.getMessage());
       }
       return null;
   }

   public static void run(String sql){
       try {
           Connection con = openConnection();
           PreparedStatement stm;
           System.out.println(sql);
           stm = con.prepareStatement(sql);
           stm.executeUpdate();
           closeConnection(con);
       } catch (SQLException ex) {
           print(ex.getMessage());
       }
   }

   private static void print(String message){
       System.out.print(message);
   }
}