java-mysqlhelper

初学java，这是自己写的mysqlhelper

package servlet;
import java.sql.*;
import java.util.*;

import javax.sql.*;
import javax.naming.InitialContext;
import javax.naming.Context;

public class Mysqlhelper {
 //public Connection con=null;
 /*public static PreparedStatement pst=null;
 public static ResultSet res=null;
 public static CallableStatement cst=null;
 */
 
 /*
  * CallableStatement 存储过程
  * PreparedStatement.executeUpdate() 处理insert、update、delete
  * PreparedStatement.executeQuery() 处理select
  * */
 //获取connection
 public Connection getconnection(){
  Connection con=null;
  try{
   Context c=new InitialContext();
   Context et=(Context)c.lookup("java:/comp/env");
   DataSource ds=(DataSource)et.lookup("jdbc/mysqldb");
   con= ds.getConnection();
   con.setAutoCommit(false);//禁止自动提交事务
  }catch(Exception e){
   System.out.println(e);
  }
  return con;
 }
 /*
  * 获取preparedstatement对象---执行sql语句
  * */
 public PreparedStatement getprepare(Connection conn,String sql){
  PreparedStatement pst=null;
  try{
   pst=conn.prepareStatement(sql);
  }catch(SQLException e){
   e.printStackTrace();
  }
  return pst;
 }
 /*
  * 获取callablestatement对象---执行存储过程*
  */
 public CallableStatement getcallable(Connection conn,String proc,String[] parm){
  CallableStatement cst=null;
  try{
   cst=conn.prepareCall(proc);
   SetParm(parm,cst);
  }catch(SQLException e){
   e.printStackTrace();
  }
  return cst;
 }
 /*
  * 执行sql语句，返回影响的记录数*
  */
 public Boolean ExecuteMysql(PreparedStatement pst){
  int re=0;
  try{
   re=pst.executeUpdate();
  }catch(Exception e){
   e.printStackTrace();
  }
  return re==0?false:true;
 }
 /*
  * 执行sql语句，返回结果集*
  */
 public ResultSet GetDatatable(PreparedStatement pst){
  ResultSet rspart=null;
  try{
   rspart=pst.executeQuery();
  }catch(Exception e){
   System.out.println(e);
  }
  return rspart;
 }
 /*
  * 执行查询存储过程*
  */
 public ResultSet Getcallparm(CallableStatement cst){
  ResultSet res=null;
  try{
   res=cst.executeQuery();
  }catch(Exception e){
   e.printStackTrace();
  }
  return res;
 }
 /*
  * 执行增删改存储过程*
  */
 public Boolean Getautocallparm(CallableStatement cst,Connection conn){
  int t=0;
  try{
   t=cst.executeUpdate();
   conn.commit();//统一提交
  }catch(Exception e){
   try{
    conn.rollback();//操作失败，事务回滚
   }catch(SQLException ex){
    ex.printStackTrace();
   }
  }
  return t==0?false:true;
 }
 /*
  * 通过execute执行存储过程 返回影响的记录数*
  */
 public int ExecuteAuto(CallableStatement cst,Connection conn){
  int i=0;
  try{
   i=cst.getUpdateCount();
   conn.commit();
  }catch(Exception e){
   try{
    e.printStackTrace();
    conn.rollback();
   }catch(SQLException ex){
    ex.printStackTrace();
   }
  }
  return i;
 }
 //使用execute()方法执行存储过程-可返回多个结果集- /*
  * 使用execute执行存储过程，可返回多个结果集
  * *
  */
 public ResultSet ExecuteSelect(CallableStatement cst,Connection conn){
  ResultSet res=null;
  try{
   cst.execute();
   res=cst.getResultSet();
   conn.commit();
  }catch(Exception e){
   try{
    e.printStackTrace();
    conn.rollback();
   }catch(SQLException ex){}
  }
  return res;
 }
 //设置存储过程的参数
 public void SetParm(String[] parm,CallableStatement cst){
  try{
   if(parm.length>0){
    for(int i=0;i<parm.length;i++){
     String s=parm[i];
     cst.setObject(i+1, s);
    }
   }
  }catch(Exception e){
   e.printStackTrace();
  }
 }
 //关闭连接
 public void closecon(Connection con){
  try{
   if(con!=null){
    con.close();
   }
  }catch(SQLException e){
   e.printStackTrace();
  }
 }
 public void closepst(PreparedStatement pst){
  try{
   if(pst!=null){
    pst.close();
   }
  }catch(SQLException e){
   e.printStackTrace();
  }
 }
 public void closecst(CallableStatement cst){
  try{
   if(cst!=null){
    cst.close();
   }
  }catch(SQLException e){
   e.printStackTrace();
  }
 }
}