2.7、orderBy 排序查询

需求：查询性别为女，，根据age进行排序（asc升序/desc降序)，默认升序

• 按age降序：

package com.wzy;
import com.baomidou.mybatisplus.mapper.EntityWrapper;
import com.baomidou.mybatisplus.plugins.Page;
import com.wzy.mapper.EmployeesMapper;
import com.wzy.pojo.Employees;
import jdk.nashorn.internal.runtime.UnwarrantedOptimismException;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;
public class TestS {
    //1.读取配置文件
    private ApplicationContext applicationContext =
            new ClassPathXmlApplicationContext("applicationContext.xml");
    private EmployeesMapper employeesMapper =
            applicationContext.getBean("employeesMapper", EmployeesMapper.class);
    private Employees employees = new Employees();
    @Test
    public void  test7() throws SQLException {
        List<Employees> list = employeesMapper.selectList(new EntityWrapper<Employees>().
                eq("gender", 0).
                orderDesc(Arrays.asList(new String[]{"age"})));
        list.forEach(list1 -> System.out.println(list1));
    }
}

输出结果：

Employees(id=4, lastName=White, email=white@atguigu.com, gender=0, age=35) Employees(id=2, lastName=Jerry, email=jerry@atguigu.com, gender=0, age=25)

• 按age升序：

package com.wzy;

import com.baomidou.mybatisplus.mapper.EntityWrapper;
import com.baomidou.mybatisplus.plugins.Page;
import com.wzy.mapper.EmployeesMapper;
import com.wzy.pojo.Employees;
import jdk.nashorn.internal.runtime.UnwarrantedOptimismException;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.Iterator;
import java.util.List;

public class TestS {
    //1.读取配置文件
    private ApplicationContext applicationContext =
            new ClassPathXmlApplicationContext("applicationContext.xml");

    private EmployeesMapper employeesMapper =
            applicationContext.getBean("employeesMapper", EmployeesMapper.class);

    @Test
    public void  test8() throws SQLException {
        List<Employees> list = employeesMapper.selectList(new EntityWrapper<Employees>().
                eq("gender", 0).
                orderBy("age"));

        list.forEach(list1 -> System.out.println(list1));
    }
}

输出结果：

Employees(id=2, lastName=Jerry, email=jerry@atguigu.com, gender=0, age=25) Employees(id=4, lastName=White, email=white@atguigu.com, gender=0, age=35)