JDBC

 

package util;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DbUtil {    
       public static final String driver = "com.mysql.jdbc.Driver";
    public static final String url = "jdbc:mysql://localhost/DbName";
    public static final String user = "root";
    public static final String password = "root";
    public static Connection conn =null;
 //构造参数   
    public DbUtil(){
       try{
           Class.forName(driver);//加载驱动程序
           conn=DriverManager.getConnection(url, user, password);//获取数据库连接
       }catch(Exception e){
           e.printStackTrace();
       }        
    }
//返回Conn    
    public static Connection getConn(){
        try{
               Class.forName(driver);
               conn = DriverManager.getConnection(url, user, password);
           }catch(Exception e){
               e.printStackTrace();
           }
        return conn;
    }
//关闭所有连接    
    // 关闭数据库
    public static void closeAll(Connection conn,ResultSet rs,Statement stat){
        if(rs!=null){
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(stat!=null){
            try {
                stat.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        if(conn!=null){
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
// 增删改
    public static boolean updateOrDel(String sql,Object[] obj) throws SQLException{
//操作数据库
        boolean flag = false;
        Connection conn = getConn();
        PreparedStatement ptp = null;
        try {
            ptp = conn.prepareStatement(sql);
            for (int i = 0; i < obj.length; i++) {
                ptp.setObject((i+1), obj[i]);
            }
            int i = ptp.executeUpdate();
            if(i>0){
                flag = true;
            }
        }finally{
            closeAll(conn, null, ptp);
        }
        return flag;
    }

}