CRUD项目

重点类容：
index.jsp:

Controller:
EmployeeController.java

package com.wj.crud.controller;
import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.wj.crud.bean.Employee;
import com.wj.crud.bean.Msg;
import com.wj.crud.service.EmployeeService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.annotation.*;
import javax.servlet.http.HttpServletRequest;
import javax.validation.Valid;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@Controller
public class EmployeeController {
    @Autowired
    EmployeeService employeeService;
    /**
     * 单个批量二合一
     * 批量删除：1-2-3
     * 单个删除：1
     *
     * @param id
     * @return
     */
    @ResponseBody
    @RequestMapping(value="/emp/{ids}",method=RequestMethod.DELETE)
    public Msg deleteEmp(@PathVariable("ids")String ids){
        //批量删除
        if(ids.contains("-")){
            List<Integer> del_ids = new ArrayList<Integer>();
            String[] str_ids = ids.split("-");
            //组装id的集合
            for (String string : str_ids) {
                del_ids.add(Integer.parseInt(string));
            }
            employeeService.deleteBatch(del_ids);
        }else{
            Integer id = Integer.parseInt(ids);
            employeeService.deleteEmp(id);
        }
        return Msg.success();
    }
    @ResponseBody
    @RequestMapping(value="/emp/{empId}",method=RequestMethod.PUT)
    public Msg updataEmp(Employee employee,HttpServletRequest request){
        System.out.println("请求体中的值："+request.getParameter("gender"));
        System.out.println("将要更新的员工数据："+employee);
        employeeService.updateEmp(employee);
        return Msg.success()    ;
    }
    //根据id查询员工数据
    @RequestMapping(value = "/emp/{id}",method = RequestMethod.GET) //处理请求 get方式就是查询
    @ResponseBody  //返回的数据用 @ResponseBody
    public Msg getEmp(@PathVariable("id") Integer id){
        //id来源于请求路径变量 @PathVariable("id")  value = "/emp/{id}
        Employee employee = employeeService.getEmp(id);
        return Msg.success().add("emp",employee);
    }
    @ResponseBody
    @RequestMapping("/checkuser")
    public Msg checkuser(String empName){
        //@Request明确的指明要取出empName值
        //先判断用户名是否是合法的表达式;
        String regx = "(^[a-zA-Z0-9_-]{6,16}$)|(^[\u2E80-\u9FFF]{2,5})";
        if(!empName.matches(regx)){
            return Msg.fail().add("va_msg", "用户名必须是6-16位数字和字母的组合或者2-5位中文");
        }
        boolean b = employeeService.checkUser(empName);
        if (b){
            return Msg.success();
        }else {
            return Msg.fail().add("va_msg","用户名不可用");
        }
    }
    @RequestMapping(value = "/emp",method = RequestMethod.POST)
    @ResponseBody
    public Msg saveEmp(@Valid Employee employee, BindingResult result){
        //BindingResult 为校验结果
        if(result.hasErrors()){
            Map<String,Object> map = new HashMap<String, Object>();
            //校验失败，应该返回失败错误信息
            List<FieldError> errors = result.getFieldErrors();
            for (FieldError fieldError : errors){
                System.out.println(fieldError.getField());
                System.out.println("错误信息："+fieldError.getDefaultMessage());
                map.put(fieldError.getField(),fieldError.getDefaultMessage());
            }
                return Msg.fail().add("errorFields",map);
        }else {
            employeeService.saveEmp(employee);
            return Msg.success();
        }
    }
    @RequestMapping("/emps")
    @ResponseBody //将返回的json对象转化为字符串 需要在pom.xml导入json包
    public Msg getEmpsWithJson(@RequestParam(value = "pn", defaultValue = "1") Integer pn){
        PageHelper.startPage(pn, 5);
        // startPage后面紧跟的这个查询就是一个分页查询
        List<Employee> emps = employeeService.getAll();
        // 使用pageInfo包装查询后的结果，只需要将pageInfo交给页面就行了。
        // 封装了详细的分页信息,包括有我们查询出来的数据，传入连续显示的页数
        PageInfo page = new PageInfo(emps, 5);
        return Msg.success().add("pageInfo",page);
    }
    //@RequestMapping("/emps")
//    public String getEmps(
//            @RequestParam(value = "pn", defaultValue = "1") Integer pn,
//            Model model) {
//        // 这不是一个分页查询；
//        // 引入PageHelper分页插件
//        // 在查询之前只需要调用，传入页码，以及每页的大小
//        PageHelper.startPage(pn, 5);
//        // startPage后面紧跟的这个查询就是一个分页查询
//        List<Employee> emps = employeeService.getAll();
//        // 使用pageInfo包装查询后的结果，只需要将pageInfo交给页面就行了。
//        // 封装了详细的分页信息,包括有我们查询出来的数据，传入连续显示的页数
//        PageInfo page = new PageInfo(emps, 5);
//        model.addAttribute("pageInfo", page);
//
//        return "list";
//    }
}

service:
EmployeeService.java

package com.wj.crud.service;

import com.wj.crud.bean.Employee;
import com.wj.crud.bean.EmployeeExample;
import com.wj.crud.dao.EmployeeMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.wj.crud.bean.EmployeeExample.Criteria;

import java.util.List;

@Service
public class EmployeeService {
    @Autowired
    EmployeeMapper employeeMapper;

    /**
     * 查询所有员工
     * @return
     */
    public List<Employee> getAll() {
        // TODO Auto-generated method stub
        return employeeMapper.selectByExampleWithDept(null);
    }

        //员工保存
    public void saveEmp(Employee employee) {
        employeeMapper.insertSelective(employee);
    }

    /**
     * 检验用户名是否可用
     *
     * @param empName
     * @return  true：代表当前姓名可用   fasle：不可用
     */
    public boolean checkUser(String empName) {
        // TODO Auto-generated method stub
        EmployeeExample example = new EmployeeExample();
        Criteria criteria = example.createCriteria();
        criteria.andEmpNameEqualTo(empName);
        long count = employeeMapper.countByExample(example);
        return count == 0;
    }

    //按照员工id查询员工
    public Employee getEmp(Integer id) {
        Employee employee = employeeMapper.selectByPrimaryKeyWithDept(id);
        return employee;
    }

    //更新员工方法
    public void updateEmp(Employee employee) {
        employeeMapper.updateByPrimaryKeySelective(employee);
    }

    public void deleteEmp(Integer id) {
        //按照主键删除
        employeeMapper.deleteByPrimaryKey(id);
    }


    public void deleteBatch(List<Integer> ids) {
        // TODO Auto-generated method stub
        EmployeeExample example = new EmployeeExample();
        Criteria criteria = example.createCriteria();
        //delete from xxx where emp_id in(1,2,3)
        criteria.andEmpIdIn(ids);
        employeeMapper.deleteByExample(example);
    }




}

dao:
EmployeeMapper.java

package com.wj.crud.dao;

import com.wj.crud.bean.Employee;
import com.wj.crud.bean.EmployeeExample;
import java.util.List;
import org.apache.ibatis.annotations.Param;
import org.springframework.stereotype.Repository;

@Repository
public interface EmployeeMapper {
    long countByExample(EmployeeExample example);

    int deleteByExample(EmployeeExample example);

    int deleteByPrimaryKey(Integer empId);

    int insert(Employee record);

    int insertSelective(Employee record);

    List<Employee> selectByExample(EmployeeExample example);

    Employee selectByPrimaryKey(Integer empId);

    List<Employee> selectByExampleWithDept(EmployeeExample example);

    Employee selectByPrimaryKeyWithDept(Integer empId);

    int updateByExampleSelective(@Param("record") Employee record, @Param("example") EmployeeExample example);

    int updateByExample(@Param("record") Employee record, @Param("example") EmployeeExample example);

    int updateByPrimaryKeySelective(Employee record);

    int updateByPrimaryKey(Employee record);
}

mapper:
EmployeeMapper.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="com.wj.crud.dao.EmployeeMapper">
  <resultMap id="BaseResultMap" type="com.wj.crud.bean.Employee">
    <id column="emp_id" jdbcType="INTEGER" property="empId" />
    <result column="emp_name" jdbcType="VARCHAR" property="empName" />
    <result column="gender" jdbcType="CHAR" property="gender" />
    <result column="email" jdbcType="VARCHAR" property="email" />
    <result column="d_id" jdbcType="INTEGER" property="dId" />
  </resultMap>
  <sql id="Example_Where_Clause">
    <where>
      <foreach collection="oredCriteria" item="criteria" separator="or">
        <if test="criteria.valid">
          <trim prefix="(" prefixOverrides="and" suffix=")">
            <foreach collection="criteria.criteria" item="criterion">
              <choose>
                <when test="criterion.noValue">
                  and ${criterion.condition}
                </when>
                <when test="criterion.singleValue">
                  and ${criterion.condition} #{criterion.value}
                </when>
                <when test="criterion.betweenValue">
                  and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
                </when>
                <when test="criterion.listValue">
                  and ${criterion.condition}
                  <foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
                    #{listItem}
                  </foreach>
                </when>
              </choose>
            </foreach>
          </trim>
        </if>
      </foreach>
    </where>
  </sql>
  <sql id="Update_By_Example_Where_Clause">
    <where>
      <foreach collection="example.oredCriteria" item="criteria" separator="or">
        <if test="criteria.valid">
          <trim prefix="(" prefixOverrides="and" suffix=")">
            <foreach collection="criteria.criteria" item="criterion">
              <choose>
                <when test="criterion.noValue">
                  and ${criterion.condition}
                </when>
                <when test="criterion.singleValue">
                  and ${criterion.condition} #{criterion.value}
                </when>
                <when test="criterion.betweenValue">
                  and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
                </when>
                <when test="criterion.listValue">
                  and ${criterion.condition}
                  <foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
                    #{listItem}
                  </foreach>
                </when>
              </choose>
            </foreach>
          </trim>
        </if>
      </foreach>
    </where>
  </sql>
  <sql id="Base_Column_List">
    emp_id, emp_name, gender, email, d_id
  </sql>






  <resultMap type="com.wj.crud.bean.Employee" id="WithDeptResultMap">
    <id column="emp_id" jdbcType="INTEGER" property="empId" />
    <result column="emp_name" jdbcType="VARCHAR" property="empName" />
    <result column="gender" jdbcType="CHAR" property="gender" />
    <result column="email" jdbcType="VARCHAR" property="email" />
    <result column="d_id" jdbcType="INTEGER" property="dId" />
    <!-- 指定联合查询出的部门字段的封装 -->
    <association property="department" javaType="com.wj.crud.bean.Department">
      <id column="dept_id" property="deptId"/>
      <result column="dept_name" property="deptName"/>
    </association>
  </resultMap>


  <sql id="WithDept_Column_List">
      e.emp_id, e.emp_name, e.gender, e.email, e.d_id,d.dept_id,d.dept_name
  </sql>

  <!-- 查询员工同时带部门信息 -->
  <select id="selectByExampleWithDept" resultMap="WithDeptResultMap">
    select
    <if test="distinct">
      distinct
    </if>
    <include refid="WithDept_Column_List" />
    FROM tbl_emp e
    left join tbl_dept d on e.`d_id`=d.`dept_id`
    <if test="_parameter != null">
      <include refid="Example_Where_Clause" />
    </if>
    <if test="orderByClause != null">
      order by ${orderByClause}
    </if>
  </select>
  <select id="selectByPrimaryKeyWithDept" resultMap="WithDeptResultMap">
    select
    <include refid="WithDept_Column_List" />
    FROM tbl_emp e
    left join tbl_dept d on e.`d_id`=d.`dept_id`
    where emp_id = #{empId,jdbcType=INTEGER}
  </select>

  <select id="selectByExample" parameterType="com.wj.crud.bean.EmployeeExample" resultMap="BaseResultMap">
    select
    <if test="distinct">
      distinct
    </if>
    <include refid="Base_Column_List" />
    from tbl_emp
    <if test="_parameter != null">
      <include refid="Example_Where_Clause" />
    </if>
    <if test="orderByClause != null">
      order by ${orderByClause}
    </if>
  </select>
  <select id="selectByPrimaryKey" parameterType="java.lang.Integer" resultMap="BaseResultMap">
    select 
    <include refid="Base_Column_List" />
    from tbl_emp
    where emp_id = #{empId,jdbcType=INTEGER}
  </select>
  <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer">
    delete from tbl_emp
    where emp_id = #{empId,jdbcType=INTEGER}
  </delete>
  <delete id="deleteByExample" parameterType="com.wj.crud.bean.EmployeeExample">
    delete from tbl_emp
    <if test="_parameter != null">
      <include refid="Example_Where_Clause" />
    </if>
  </delete>
  <insert id="insert" parameterType="com.wj.crud.bean.Employee">
    insert into tbl_emp (emp_id, emp_name, gender, 
      email, d_id)
    values (#{empId,jdbcType=INTEGER}, #{empName,jdbcType=VARCHAR}, #{gender,jdbcType=CHAR}, 
      #{email,jdbcType=VARCHAR}, #{dId,jdbcType=INTEGER})
  </insert>
  <insert id="insertSelective" parameterType="com.wj.crud.bean.Employee">
    insert into tbl_emp
    <trim prefix="(" suffix=")" suffixOverrides=",">
      <if test="empId != null">
        emp_id,
      </if>
      <if test="empName != null">
        emp_name,
      </if>
      <if test="gender != null">
        gender,
      </if>
      <if test="email != null">
        email,
      </if>
      <if test="dId != null">
        d_id,
      </if>
    </trim>
    <trim prefix="values (" suffix=")" suffixOverrides=",">
      <if test="empId != null">
        #{empId,jdbcType=INTEGER},
      </if>
      <if test="empName != null">
        #{empName,jdbcType=VARCHAR},
      </if>
      <if test="gender != null">
        #{gender,jdbcType=CHAR},
      </if>
      <if test="email != null">
        #{email,jdbcType=VARCHAR},
      </if>
      <if test="dId != null">
        #{dId,jdbcType=INTEGER},
      </if>
    </trim>
  </insert>
  <select id="countByExample" parameterType="com.wj.crud.bean.EmployeeExample" resultType="java.lang.Long">
    select count(*) from tbl_emp
    <if test="_parameter != null">
      <include refid="Example_Where_Clause" />
    </if>
  </select>
  <update id="updateByExampleSelective" parameterType="map">
    update tbl_emp
    <set>
      <if test="record.empId != null">
        emp_id = #{record.empId,jdbcType=INTEGER},
      </if>
      <if test="record.empName != null">
        emp_name = #{record.empName,jdbcType=VARCHAR},
      </if>
      <if test="record.gender != null">
        gender = #{record.gender,jdbcType=CHAR},
      </if>
      <if test="record.email != null">
        email = #{record.email,jdbcType=VARCHAR},
      </if>
      <if test="record.dId != null">
        d_id = #{record.dId,jdbcType=INTEGER},
      </if>
    </set>
    <if test="_parameter != null">
      <include refid="Update_By_Example_Where_Clause" />
    </if>
  </update>
  <update id="updateByExample" parameterType="map">
    update tbl_emp
    set emp_id = #{record.empId,jdbcType=INTEGER},
      emp_name = #{record.empName,jdbcType=VARCHAR},
      gender = #{record.gender,jdbcType=CHAR},
      email = #{record.email,jdbcType=VARCHAR},
      d_id = #{record.dId,jdbcType=INTEGER}
    <if test="_parameter != null">
      <include refid="Update_By_Example_Where_Clause" />
    </if>
  </update>
  <update id="updateByPrimaryKeySelective" parameterType="com.wj.crud.bean.Employee">
    update tbl_emp
    <set>
      <if test="empName != null">
        emp_name = #{empName,jdbcType=VARCHAR},
      </if>
      <if test="gender != null">
        gender = #{gender,jdbcType=CHAR},
      </if>
      <if test="email != null">
        email = #{email,jdbcType=VARCHAR},
      </if>
      <if test="dId != null">
        d_id = #{dId,jdbcType=INTEGER},
      </if>
    </set>
    where emp_id = #{empId,jdbcType=INTEGER}
  </update>
  <update id="updateByPrimaryKey" parameterType="com.wj.crud.bean.Employee">
    update tbl_emp
    set emp_name = #{empName,jdbcType=VARCHAR},
      gender = #{gender,jdbcType=CHAR},
      email = #{email,jdbcType=VARCHAR},
      d_id = #{dId,jdbcType=INTEGER}
    where emp_id = #{empId,jdbcType=INTEGER}
  </update>
</mapper>