springmvc-mybatis的增删改查以及主键返回

基于原始dao开发，而不是mapper代理

1.usermapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">


<mapper namespace="cn.itcast.ssm.mapper.UserMapper">

    <!-- #{}表示一个占位符 根据id查询用户-->
    <select id="findUserById" parameterType="int" resultType="com.ssm.model.User">
        SELECT * FROM USER WHERE id=#{value}
    </select>

    <!-- ${}表示拼接sql字符串 根据姓名模糊查询用户 
        可能会造成sql注入为题，如果接收的参数为简单类型，只能为${value} 与 #{}不一样，可是使用任何名称
    -->
    <select id="findUserByName" parameterType="java.lang.String" resultType="com.ssm.model.User">
        SELECT * FROM USER WHERE USERNAME LIKE '%${value}%'
    </select>

    <!-- 插入新用户   自增主键的返回-->
    <insert id="insertUser" parameterType="com.ssm.model.User">
        <selectKey keyProperty="id" order="AFTER" resultType="java.lang.Integer">
            SELECT LAST_INSERT_ID()
        </selectKey>
        <!-- 非自增主键的返回 通过uuid() 
        <selectKey keyProperty="id" order="before" resultType="java.lang.String">
            SELECT　uuid()
        </selectKey>
        如果通过这个方式 那么插入语句为
        insert into user(id,username,password) values (#{id},#{username},#{password})
        -->
        insert into user(username,password) values (#{username},#{password})
    </insert>


    <!-- 删除用户 -->
    <delete id="deleteUser" parameterType="java.lang.Integer">
        delete from user where id=#{id}
    </delete>

    <!-- 更新用户 -->
    <update id="updateUser" parameterType="com.ssm.model.User">
        update user set username=#{username},password=#{password} where id=#{id}
    </update>
</mapper>

2.userdao.java

package com.ssm.dao;

import java.util.List;

import com.ssm.model.User;

public interface UserDAO {

    public User selectByID(int id);
    public List<User> findUserByName(String username);
    public void insertUser(User user);
    public void deleteUser(int id);
    public void updateUser(User user);
}

//dao实现

package com.ssm.dao.impl;

import java.util.List;

import org.apache.ibatis.session.SqlSession;
import org.mybatis.spring.support.SqlSessionDaoSupport;

import com.ssm.dao.UserDAO;
import com.ssm.model.User;

public class UserDAOImpl extends SqlSessionDaoSupport implements UserDAO {

    @Override
    public User selectByID(int id) {
        SqlSession sqlsession = this.getSqlSession();

        User user = sqlsession.selectOne("findUserById", id);
        return user;
    }

    @Override
    public List<User> findUserByName(String username) {
        List<User> list = null;
        list = this.getSqlSession().selectList("findUserByName", username);
        return list;
    }

    @Override
    public void insertUser(User user) {
        this.getSqlSession().insert("insertUser", user);
    }

    @Override
    public void deleteUser(int id) {
        this.getSqlSession().delete("deleteUser", id);
    }

    @Override
    public void updateUser(User user) {
        this.getSqlSession().update("updateUser", user);
    }


}

3.springmvc控制器

package com.ssm.controller;

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

import com.ssm.dao.UserDAO;
import com.ssm.model.User;


@Controller
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserDAO dao;

    @RequestMapping(value="/select",method=RequestMethod.GET)
    public String selectById(@RequestParam("id")int id)
    {
        System.out.println("test");
        User user = dao.selectByID(id);
        System.out.println(user.toString());
        return "index";
    }

    @RequestMapping(value="/selectbyname",method=RequestMethod.GET)
    public String findUserByName(@RequestParam("username")String username,HttpServletRequest request)
    {
        List<User> list = dao.findUserByName(username);
        request.setAttribute("userlist", list);

        return "user";
    }

    //测试，主动生成User算了
    @RequestMapping(value="/insert",method=RequestMethod.GET)
    public String insertUser()
    {
        User user = new User();
        user.setPassword("insert");
        user.setUsername("insert");
        dao.insertUser(user);
        System.out.println(user.getId());
        return "index";
    }

    @RequestMapping(value="/delete",method=RequestMethod.GET)
    public String deleteUser(@RequestParam("id")int id)
    {
        dao.deleteUser(id);
        return "index";
    }
    @RequestMapping(value="/update",method=RequestMethod.GET)
    public String updateUser()
    {
        User user = new User();
        user.setId(8);
        user.setPassword("insertAfter");
        user.setUsername("insertAfter");
        dao.updateUser(user);
        return "index";
    }


}

，以上