条件分页查询

java 复制代码

@GetMapping
    public Result page(@RequestParam(defaultValue = "1") Integer page,
                       @RequestParam (defaultValue = "10") Integer pageSize,
                       String name, Integer gender,
                       //日期格式封装到LocalDate需要指定前端传递过来的日期时间格式
                       @DateTimeFormat(pattern = "yyyy-MM-dd")LocalDate begin,
                       @DateTimeFormat(pattern = "yyyy-MM-dd")LocalDate end
                       ){

        log.info("分页查询:{},{},{},{},{},{}",page,pageSize,name,gender,begin,end);
        PageResult<Emp> pageResult = empService.page(page,pageSize,name,gender,begin,end);
        return Result.success(pageResult);
    }

java 复制代码

 @Override
    public PageResult<Emp> page(Integer page, Integer pageSize,String name, Integer gender, LocalDate begin, LocalDate end) {
        //设置分页参数(Pagehelper)
        PageHelper.startPage(page, pageSize);
        //执行查询
        List<Emp> empList = empMapper.list(name,gender,begin, end);
        //解析查询结果，并封装
        Page<Emp> p = (Page<Emp>) empList;
        return new PageResult<>(p.getTotal(),p.getResult());
    }

java 复制代码

    public List<Emp> list(String name, Integer gender, LocalDate begin, LocalDate end);

java 复制代码

<?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.itheima.mapper.EmpMapper">

    <select id="list" resultType="com.itheima.pojo.Emp">
        select e.*,d.name from emp e left join dept d on e.dept_id = d.id
                          where e.name like concat('%',#{name},'%') and
                                e.gender = #{gender} and e.entry_date between #{begin} and #{end}
                          order by e.update_time

    </select>
</mapper>

java 复制代码

package com.itheima.pojo;

import lombok.Data;
import org.springframework.format.annotation.DateTimeFormat;
import java.time.LocalDate;

@Data
public class EmpQueryParam {
    
    private Integer page = 1; //页码
    private Integer pageSize = 10; //每页展示记录数
    private String name; //姓名
    private Integer gender; //性别
    @DateTimeFormat(pattern = "yyyy-MM-dd")
    private LocalDate begin; //入职开始时间
    @DateTimeFormat(pattern = "yyyy-MM-dd")
    private LocalDate end; //入职结束时间
    
}

java 复制代码

@GetMapping
public Result page(EmpQueryParam empQueryParam) {
    log.info("查询请求参数： {}", empQueryParam);
    PageResult pageResult = empService.page(empQueryParam);
    return Result.success(pageResult);
}

java 复制代码

public interface EmpService {
    /**
     * 分页查询
     */
    //PageResult page(Integer page, Integer pageSize, String name, Integer gender, LocalDate begin, LocalDate end);
    PageResult page(EmpQueryParam empQueryParam);
}

java 复制代码

@Service
public class EmpServiceImpl implements EmpService {

    @Autowired
    private EmpMapper empMapper;

    /*@Override
    public PageResult page(Integer page, Integer pageSize, String name, Integer gender, LocalDate begin, LocalDate end) {
        //1. 设置PageHelper分页参数
        PageHelper.startPage(page, pageSize);
        //2. 执行查询
        List<Emp> empList = empMapper.list(name, gender, begin, end);
        //3. 封装分页结果
        Page<Emp> p = (Page<Emp>) empList;
        return new PageResult(p.getTotal(), p.getResult());
    }*/

    public PageResult page(EmpQueryParam empQueryParam) {
        //1. 设置PageHelper分页参数
        PageHelper.startPage(empQueryParam.getPage(), empQueryParam.getPageSize());
        //2. 执行查询
        List<Emp> empList = empMapper.list(empQueryParam);
        //3. 封装分页结果
        Page<Emp> p = (Page<Emp>)empList;
        return new PageResult(p.getTotal(), p.getResult());
    }
}

java 复制代码

@Mapper
public interface EmpMapper {

    /**
     * 查询所有的员工及其对应的部门名称
     */
//    @Select("select e.*, d.name as deptName from emp e left join dept d on e.dept_id = d.id")
//    public List<Emp> list(String name, Integer gender, LocalDate begin, LocalDate end);
    
    /**
     * 根据查询条件查询员工
     */
    List<Emp> list(EmpQueryParam empQueryParam);
}