MyBatis Plus 分页

一、分页插件

MyBatis Plus自带分页插件，只要简单的配置即可实现分页功能

1、添加配置类

@Configuration
public class MyConfig {@Beanpublic MybatisPlusInterceptor mybatisPlusInterceptor() {MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();interceptor.addInnerInterceptor(newPaginationInnerInterceptor(DbType.MYSQL));//添加乐观锁插件interceptor.addInnerInterceptor(new OptimisticLockerInnerInterceptor());return interceptor;}
}

2、测试

@Test
public void testPage() {Page<User> page = new Page<>(1, 5);Page<User> page1 = userService.page(page);System.out.println("总页数："+page1.getPages());System.out.println("总记录数："+page1.getTotal());System.out.println("当前页内容："+page1.getRecords());System.out.println("当前页："+page1.getCurrent());System.out.println("每页显示的条数："+page1.getSize());System.out.println("是否有上一页："+page1.hasPrevious());System.out.println("是否有下一页："+page1.hasNext());
}

输出：

总页数：8
总记录数：39
当前页内容：[User(id=2, name=韩梅梅, age=28, email=123@qq.com), User(id=3, name=王刚, age=28, email=123@qq.com), User(id=4, name=张婷, age=28, email=123@qq.com), User(id=5, name=赵强, age=28, email=123@qq.com), User(id=6, name=孙丽, age=28, email=123@qq.com)]
当前页：1
每页显示的条数：5
是否有上一页：false
是否有下一页：true

二、XML 自定义分页

1、UserMapper 中自定义接口方法

/*** 自定义分页* @param page:传入分页对象进行分页，SQL中不需要对该参数进行处理* @param name:条件查询参数* @return*/
Page<User> myselfSelectPage(@Param("page") Page<User> page, @Param("name") String name);

2、UserMapper.xml 中编写SQL语句

注意xml文件位置，存放在 /resources/mappers/ 下

<?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.goose.mapper.UserMapper"><sql id="BaseColumns">id,`name`,age,email</sql><select id="myselfSelectPage" resultType="com.goose.entity.User">select <include refid="BaseColumns"/> from `user` where name like concat('%',#{name},'%')</select></mapper>

3、yml 配置文件

指定 .xml 配置文件位置

mybatis-plus:# 配置MyBatis日志configuration:log-impl: org.apache.ibatis.logging.stdout.StdOutImpl# 指定 .xml 配置文件位置mapper-locations: classpath*:mappers/*.xml

4、测试

@Test
public void testMyPage() {Page<User> page = new Page<>(1, 5);// ==>  Preparing: SELECT COUNT(*) AS total FROM `user` WHERE name LIKE concat('%', ?, '%')// ==>  Preparing: select id,`name`,age,email from `user` where name like concat('%',?,'%') LIMIT ?Page<User> page1 = userService.myselfSelectPage(page, "浩");System.out.println("总页数："+page1.getPages());System.out.println("总记录数："+page1.getTotal());System.out.println("当前页内容："+page1.getRecords());
}

输出：

总页数：1
总记录数：2
当前页内容：[User(id=11, name=郑浩, age=28, email=123@qq.com), User(id=32, name=龚加浩, age=28, email=123@qq.com)]