JSP 水费管理系统 myeclipse开发 web网页mysql数据库java编程

package com.util; import java.sql.*; import javax.activation.DataSource; import java.sql.*; import javax.naming.Context; import javax.naming.InitialContext; import java.util.*; public class DBO { private Connection conn; private Statement stmt; private DataSource ds; public DBO() { open(); } /** 打开数据库 */ public void open() { String driver = "com.mysql.jdbc.Driver"; String url = "jdbc:mysql://127.0.0.1:3306/jspshuifei?characterEncoding=gb2312&mysqlEncoding=gb2312"; // MySQL配置时的用户名 String user = "root"; // MySQL配置时的密码 String password = "abc123"; try { Class.forName(driver); conn = DriverManager.getConnection(url, user, password); stmt=conn.createStatement(); System.out.println("打开数据库连接"); } catch (Exception ex) { System.err.println("打开数据库时出错: " + ex.getMessage()); } } /** 关闭数据库，将连接返还给连接池 */ public void close() { try { // connMgr.freeConnection("java", conn); conn.close(); System.out.println ("释放连接"); } catch (SQLException ex) { System.err.println("返还连接池出错: " + ex.getMessage()); } } /** 执行查询 */ public ResultSet executeQuery(String sql) throws SQLException { ResultSet rs = null; rs = stmt.executeQuery(sql); System.out.println ("执行查询"); return rs; } public ResultSet query(String sql) throws SQLException { ResultSet rs = null; System.out.println(sql); rs = stmt.executeQuery(sql); System.out.println ("执行查询"); return rs; } /** 执行增删改 */ public int executeUpdate(String sql) throws SQLException { int ret = 0; ret = stmt.executeUpdate(sql); System.out.println ("执行增删改"); return ret; } public int update(String sql) throws SQLException { int ret = 0; ret = stmt.executeUpdate(sql); System.out.println ("执行增删改"); return ret; } /** 将SQL语句加入到批处理 */ public void addBatch(String sql) throws SQLException { stmt.addBatch(sql); } /** 执行批处理 */ public int [] executeBatch() throws SQLException { boolean isAuto=conn.getAutoCommit(); conn.setAutoCommit(false); int [] updateCounts = stmt.executeBatch(); // conn.commit(); // conn.setAutoCommit(isAuto); //conn.setAutoCommit(true); return updateCounts; } public boolean getAutoCommit() throws SQLException { return conn.getAutoCommit(); } public void setAutoCommit(boolean auto) throws SQLException { conn.setAutoCommit(auto); } public void commit() throws SQLException { conn.commit(); // this.close(); } public void rollBack() throws SQLException { conn.rollback(); // this.close(); } public static void main(String[] args) { DBO con= new DBO(); //con.open(); // ResultSet rs=null; // String sql="select id dd from didian"; // List list=new ArrayList(); // //ResultSet rs=null; // // // try{ // rs=con.executeQuery(sql); // }catch(Exception e){ // System.out.println(e.toString()); // // } con.close(); } }