bitscn.com //接口类package com.syxy.dao;import com.syxy.domain.user;//操纵数据库的 dao接口public interface userdao { //加入一个用户 public void adduser(user user); //得到一个用户 public user getuser( int userid); //寻找一个用户 public user finduser(string loginname); //更新用户数据 public void update(user user); //删除一个用户 public void delete(user user);}//接口的实现类package com.syxy.dao.impl;import java.sql.connection;import java.sql.preparedstatement;import java.sql.resultset;import java.sql.sqlexception;import com.syxy.dao.userdao;import com.syxy.domain.user;import com.syxy.utils.jdbcutils;public class userdaojdbcimpl implements userdao { @override public void adduser(user user) { // todo auto-generated method stub connection conn = null; preparedstatement ps = null; resultset rs = null; try { conn = jdbcutils.getconnection(); string sql = insert into user(name, birthday, monery) values(?,?,?); ps = conn.preparestatement(sql); ps.setstring(1, user.getname()); ps.setdate(2, new java.sql.date(user.getbirthday().gettime())); ps.setfloat(3, user.getmoney()); ps.executeupdate(); } catch (exception e) { e.printstacktrace(); }finally{ jdbcutils.free(rs, ps, conn); } } @override public user getuser(int userid) { connection conn = null; preparedstatement ps = null; resultset rs = null; user user = null; try { conn = jdbcutils.getconnection(); string sql = select id，name,money,birthday from user where id=?; ps = conn.preparestatement(sql); ps.setint(1, userid); rs = ps.executequery(); while(rs.next()){ user = mappinguser(rs); } } catch (exception e) { e.printstacktrace(); }finally{ jdbcutils.free(rs, ps, conn); } return user; } @override public user finduser(string loginname) { connection conn = null; preparedstatement ps = null; resultset rs = null; user user = null; try { conn = jdbcutils.getconnection(); string sql = select id,money,birthday from user where name=?; ps = conn.preparestatement(sql); ps.setstring(1, loginname); rs = ps.executequery(); while(rs.next()){ user = mappinguser(rs); } } catch (exception e) { e.printstacktrace(); }finally{ jdbcutils.free(rs, ps, conn); } return user; } private user mappinguser(resultset rs) throws sqlexception { user user = new user(); user.setid(rs.getint(id)); user.setname(rs.getstring(name)); user.setmoney(rs.getfloat(money)); user.setbirthday(rs.getdate(birthday)); return user; } @override public void update(user user) { connection conn = null; preparedstatement ps = null; resultset rs = null; try { conn = jdbcutils.getconnection(); string sql = update user set name=?, birthday=?, money=? where id=?; ps = conn.preparestatement(sql); ps.setstring(1, user.getname()); ps.setdate(2, new java.sql.date(user.getbirthday().gettime())); ps.setfloat(3, user.getmoney()); ps.setint(4, user.getid()); ps.executeupdate(); } catch (exception e) { e.printstacktrace(); }finally{ jdbcutils.free(rs, ps, conn); } } @override public void delete(user user) { connection conn = null; preparedstatement ps = null; resultset rs = null; try { conn = jdbcutils.getconnection(); string sql = delete from user where id=?; ps = conn.preparestatement(sql); ps.setint(1, user.getid()); ps.executeupdate(); } catch (exception e) { e.printstacktrace(); }finally{ jdbcutils.free(rs, ps, conn); } }}//domain用户类package com.syxy.domain;import java.util.date;public class user { private int id ; private string name ; private date birthday ; private float money ; public int getid() { return id ; } public void setid( int id) { this .id = id; } public string getname() { return name ; } public void setname(string name) { this .name = name; } public date getbirthday() { return birthday ; } public void setbirthday(date birthday) { this .birthday = birthday; } public float getmoney() { return money ; } public void setmoney( float money) { this .money = money; } }//dao工厂类（方便复用）package com.syxy.dao;import java.io.file;import java.io.fileinputstream;import java.io.inputstream;import java.util.properties;public class daofactory { private static userdao userdao = null ; private static daofactory instance = new daofactory(); private daofactory(){ try { properties prop = new properties(); inputstream instream = new fileinputstream( new file(src/daoconfig.properties )); prop.load(instream); string userdaoclass = prop.getproperty(userdaoclass ); userdao = (userdao) class.forname(userdaoclass).newinstance(); } catch (exception e) { // todo: handle exception } } public static daofactory getinstance(){ return instance ; } public userdao getuserdao(){ return userdao ; }}//操作数据库的工具类package com.syxy.utils;import java.sql.connection;import java.sql.drivermanager;import java.sql.resultset;import java.sql.sqlexception;import java.sql.statement;public final class jdbcutils { private static string url = jdbc：mysql://localhost:3306/jdbc; private static string user = root; private static string password = lxtalx; private jdbcutils(){} static{ try { class.forname(com.mysql.jdbc.driver); } catch (classnotfoundexception e) { throw new exceptionininitializererror(e); } } public static connection getconnection() throws sqlexception{ return drivermanager.getconnection(url, user, password); } public static void free(resultset rs, statement st, connection conn){ try { if(rs!=null) rs.close(); } catch (exception e) { e.printstacktrace(); }finally{ try { if(st!=null) st.close(); } catch (exception e2) { e2.printstacktrace(); }finally{ try { conn.close(); } catch (exception e3) { e3.printstacktrace(); } } } }}
bitscn.com