springBoot集成mybatis-plus
springBoot集成mybatis-plus
- 1.环境搭建
- 2.造数据代码
- 3.CRUD 接口
-
- 1.如何配置统一的逻辑删除
- 2.pojo层的CRUD 接口
- 3.mapper层的CRUD 接口
- 4.service层的CRUD 接口
- 4.新增或删除如何用
-
- 1.pojo层的方法为：insertOrUpdate()
- 2.mapper层没有
- 3.service层的方法为：saveOrUpdate()
- 5.分页查询
-
- 1.在代码中的用法
- 2.xml文件中的使用
1.环境搭建
1.sql
CREATE TABLE `t_user` (
`id` bigint NOT NULL AUTO_INCREMENT COMMENT 'id',
`name` varchar(32) COLLATE utf8mb4_general_ci NOT NULL COMMENT '姓名',
`age` int NOT NULL COMMENT '年龄',
`password` varchar(20) COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '密码',
`sex` char(8) COLLATE utf8mb4_general_ci NOT NULL,
`create_time` timestamp(6) NULL DEFAULT NULL,
`is_del` tinyint(1) DEFAULT '0',
PRIMARY KEY (`id`),
UNIQUE KEY `t_user_pk2` (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci COMMENT='用户表';
2.创建maven工程并且导入坐标
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0modelVersion>
<groupId>com.andygroupId>
<artifactId>springboot_crudartifactId>
<version>1.0-SNAPSHOTversion>
<properties>
<maven.compiler.source>11maven.compiler.source>
<maven.compiler.target>11maven.compiler.target>
<project.build.sourceEncoding>UTF-8project.build.sourceEncoding>
properties>
<parent>
<artifactId>spring-boot-starter-parentartifactId>
<groupId>org.springframework.bootgroupId>
<version>2.7.13version>
parent>
<dependencies>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-testartifactId>
dependency>
<dependency>
<groupId>junitgroupId>
<artifactId>junitartifactId>
<version>4.13.2version>
<scope>testscope>
dependency>
<dependency>
<groupId>org.springframework.bootgroupId>
<artifactId>spring-boot-starter-data-restartifactId>
dependency>
<dependency>
<groupId>com.alibaba.fastjson2groupId>
<artifactId>fastjson2artifactId>
<version>2.0.40version>
dependency>
<dependency>
<groupId>mysqlgroupId>
<artifactId>mysql-connector-javaartifactId>
<version>8.0.33version>
dependency>
<dependency>
<groupId>org.projectlombokgroupId>
<artifactId>lombokartifactId>
<version>1.18.26version>
<scope>providedscope>
dependency>
<dependency>
<groupId>com.baomidougroupId>
<artifactId>mybatis-plus-boot-starterartifactId>
<version>3.5.3.1version>
dependency>
dependencies>
project>
3.application.yml文件中的配置
spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/study_test
username: root
password: root
mybatis-plus:
# 包扫描
type-aliases-package: com.andy.pojo
# 加载Mapper.xml文件
mapper-locations: classpath:/mapper/*.xml
configuration:
# 输出日志
log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
4.pojo层
package com.andy.pojo;
import com.alibaba.fastjson2.annotation.JSONField;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableLogic;
import com.baomidou.mybatisplus.annotation.TableName;
import com.baomidou.mybatisplus.extension.activerecord.Model;
import com.fasterxml.jackson.annotation.JsonIgnore;
import lombok.Data;
import lombok.EqualsAndHashCode;
import java.sql.Timestamp;
@Data
@EqualsAndHashCode(callSuper = true)
@TableName(value = "t_user")
public class User extends Model<User> {
private static final long serialVersionUID = 3404898457642193846L;
/**
* ID
*/
@TableId(value = "id",type = IdType.AUTO)
@JSONField(ordinal = 0)
private Long id;
/**
* 姓名
*/
@JSONField(ordinal = 1)
private String name;
/**
* 密码
*/
@JSONField(ordinal = 2)
private String password;
/**
* 年龄
*/
@JSONField(ordinal = 3)
private Integer age;
/**
* 性别
*/
@JSONField(ordinal = 4)
private String sex;
/**
* 时间
*/
@JSONField(ordinal = 5)
private Timestamp createTime;
/**
* 逻辑删除
*/
@TableLogic
@JsonIgnore
private Boolean isDel;
}
4.mapper层
package com.andy.mapper;
import com.andy.pojo.User;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
/**
* @author andy
*/
@Mapper
public interface UserMapper extends BaseMapper<User> {
}
5.service层
package com.andy.service;
import com.andy.pojo.User;
import com.baomidou.mybatisplus.extension.service.IService;
public interface IUserService extends IService<User> {
}
6.serviceImpl层
package com.andy.service.impl;
import com.andy.mapper.UserMapper;
import com.andy.pojo.User;
import com.andy.service.IUserService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.stereotype.Service;
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {
}
7.测试类代码
package com.andy.mybatis.user;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
/**
* @author Andy
* @version 0.0.1
* @since 2023-10-11 14:22
*/
@SpringBootTest
@RunWith(SpringRunner.class)
public class TestService {
}
2.造数据代码
1.在service层定义
/**
* 测试数据
* @param startId 开始id
* @param endId 结束ID
* @throws InterruptedException /
*/
void saveTest(Integer startId, Integer endId) throws InterruptedException;
2.实现saveTest接口
@Override
@Transactional(rollbackFor = Exception.class)
public void saveTest(Integer startId, Integer endId) throws InterruptedException {
ThreadLocalRandom current = ThreadLocalRandom.current();
List<User> users = new ArrayList<>(endId + 1);
for (int i = startId; i < endId + 1; i++) {
User userTest = new User();
userTest.setId((long) i);
userTest.setName(getName());
userTest.setPassword(String.valueOf(current.nextInt(100000,1000000)));
userTest.setSex(String.valueOf(current.nextInt(0, 2)).equals("1") ?"男":"女");
userTest.setAge(current.nextInt(10, 50));
userTest.setCreateTime(new Timestamp(ThreadLocalRandom.current().nextLong(1307008513279L,1697008513279L)));
userTest.setIsDel(Boolean.FALSE);
users.add(userTest);
}
Integer index = startId;
List<User> sortedUsers = users.stream().sorted(Comparator.comparing(User::getCreateTime)).collect(Collectors.toList());
for (User sortedUser : sortedUsers) {
sortedUser.setId((long) startId);
startId++;
}
this.saveBatch(sortedUsers);
}
// 姓氏池
private static final String SURNAME = "赵钱孙李周吴郑王冯陈卫蒋沈韩杨朱许";
// 名字池
private static final String NAME = "三四五六七八安星楠希拧允言遥初乐依宇苏思诺";
public static String getName() {
// 开局获取一个姓氏池的随机下标
int surnameLength = (int) (Math.random() * (SURNAME.length()));
// 通过下标随机获取到一个姓氏
char c = SURNAME.charAt(surnameLength);
// 创建一个可扩容字符串
StringBuilder userName = new StringBuilder();
// 将随机获取到的姓氏拼接
userName.append(c);
// 随机(1,3]的随机数（一般名字要么是两个字要么一个字）
int nameLength = (int) (Math.random() * 3);
// 判断随机数是否大于1 如果大于 1那么就进行两次随机获取名字池的某个字符，进行拼接
if (nameLength > 1) {
// int i1 = (int) (Math.random() * (NAME.length()));
int i1 = ThreadLocalRandom.current().nextInt(NAME.length());
char c1 = NAME.charAt(i1);
// int i2 = (int) (Math.random() * (NAME.length()));
int i2 = ThreadLocalRandom.current().nextInt(NAME.length());
char c2 = NAME.charAt(i2);
userName.append(c1);
userName.append(c2);
return String.valueOf(userName);
// 其他情况下就是一个字的名字，只获取一个字
} else {
int i1 = (int) (Math.random() * (NAME.length()));
char c1 = NAME.charAt(i1);
userName.append(c1);
return String.valueOf(userName);
}
}
3.在测试类TestService编写代码：
@Resource
private IUserService userService;
/**
* 生成测试数据
*/
@Test
public void testDataSave() throws InterruptedException {
userService.saveTest(1,5);
}
4.运行结果
5.数据库验证查询
select * from t_user;
3.CRUD 接口
1.如何配置统一的逻辑删除
1.案例如下：
删除: update user set is_del=1 where id = 1 and is_del=0
查找: select id,name,is_del from user where is_del=0
2.在yml文件中配置如下内容：
mybatis-plus:
global-config:
db-config:
# 全局逻辑删除字段
logic-delete-field: is_del
# 逻辑已删除值(默认为 1)
logic-delete-value: 1
# 逻辑未删除值(默认为 0)
logic-not-delete-value: 0
2.pojo层的CRUD 接口
1.新增
@Test
public void testPojoSave(){
User user = new User();
user.setName("root");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
// 新增
user.insert();
}
2.查询
@Test
public void testPojoRead(){
User user = new User();
// 查询所有
System.out.println(user.selectAll());
// 更具ID查询
System.out.println(user.selectById(1));
}
3.更新
@Test
public void testPojoUpdate(){
User user = new User();
// id必须有
user.setId(1L);
user.setName("aaa");
user.updateById();
}
4.删除(逻辑删除)
@Test
public void testPojoDelete(){
User user = new User();
user.setId(1L);
user.deleteById();
}
数据库验证SQL：
select * from t_user
5.本节完整代码
package com.andy.mybatis.user;
import com.andy.pojo.User;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import java.sql.Timestamp;
/**
* @author Andy
* @version 0.0.1
* @since 2023-10-12 11:12
*/
@SpringBootTest
@RunWith(SpringRunner.class)
public class TestPojo {
/**
* 新增
*/
@Test
public void testPojoSave(){
User user = new User();
user.setName("root");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
// 新增
user.insert();
}
/**
* 查询
*/
@Test
public void testPojoRead(){
User user = new User();
// 查询所有
System.out.println(user.selectAll());
// 更具ID查询
System.out.println(user.selectById(1));
}
/**
* 修改
*/
@Test
public void testPojoUpdate(){
User user = new User();
// id必须有
user.setId(1L);
user.setName("aaa");
user.updateById();
}
/**
* 逻辑删除
*/
@Test
public void testPojoDelete(){
User user = new User();
user.setId(1L);
user.deleteById();
}
}
3.mapper层的CRUD 接口
注意：使用Mapper层时要将Mapper进行注入：代码如下
@Resource private UserMapper userMapper;
1.新增
@Test
public void testMapperSave(){
User user = new User();
user.setName("bbb");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("女");
userMapper.insert(user);
}
数据库验证SQL
select * from t_user
2.查询
@Test
public void testMapperRead(){
System.out.println(userMapper.selectById(1L));
System.out.println(userMapper.selectList(null));
}
3.更新
@Test
public void testMapperUpdate(){
User user = new User();
user.setId(7L);
user.setSex("男");
userMapper.updateById(user);
}
4.删除
public void testMapperDelete(){
userMapper.deleteById(2L);
}
数据库验证SQL
select * from t_user
5.本节完整代码
package com.andy.mybatis.user;
import com.andy.mapper.UserMapper;
import com.andy.pojo.User;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import javax.annotation.Resource;
import java.sql.Timestamp;
/**
* @author Andy
* @version 0.0.1
* @since 2023-10-12 14:23
*/
@SpringBootTest
@RunWith(SpringRunner.class)
public class TestMapper {
@Resource
private UserMapper userMapper;
/**
* 新增
*/
@Test
public void testMapperSave(){
User user = new User();
user.setName("bbb");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("女");
userMapper.insert(user);
}
/**
* 查询
*/
@Test
public void testMapperRead(){
// 根据ID查询
System.out.println(userMapper.selectById(1L));
// 查询所有
System.out.println(userMapper.selectList(null));
}
/**
* 更新
*/
@Test
public void testMapperUpdate(){
User user = new User();
user.setId(7L);
user.setSex("男");
userMapper.updateById(user);
}
/**
* 逻辑删除
*/
@Test
public void testMapperDelete(){
userMapper.deleteById(2L);
}
}
4.service层的CRUD 接口
注意：使用Mapper层时要将Mapper进行注入：代码如下
@Resource private IUserService userService;
1.新增
@Test
public void testServiceSave() {
User user = new User();
user.setName("root");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
userService.save(user);
}
2.查询
@Test
public void testServiceRead() {
// 查询所有
System.out.println(userService.list());
// 根据ID查询
System.out.println(userService.getById(1L));
}
3.更新
@Test
public void testServiceUpdate() {
User user = new User();
user.setId(8L);
user.setName("ccc");
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
userService.updateById(user);
}
4.删除
@Test
public void testServiceDelete() {
userService.removeById(3L);
}
5.本节完整代码
package com.andy.mybatis.user;
import com.andy.pojo.User;
import com.andy.service.IUserService;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import javax.annotation.Resource;
import java.sql.Timestamp;
/**
* @author Andy
* @version 0.0.1
* @since 2023-10-12 14:22
*/
@SpringBootTest
@RunWith(SpringRunner.class)
public class TestService {
@Resource
private IUserService userService;
/**
* 新增
*/
@Test
public void testServiceSave() {
User user = new User();
user.setName("root");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
userService.save(user);
}
/**
* 查询
*/
@Test
public void testServiceRead() {
// 查询所有
System.out.println(userService.list());
// 根据ID查询
System.out.println(userService.getById(1L));
}
/**
* 修改
*/
@Test
public void testServiceUpdate() {
User user = new User();
user.setId(8L);
user.setName("ccc");
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
userService.updateById(user);
}
/**
* 删除
*/
@Test
public void testServiceDelete() {
userService.removeById(3L);
}
}
4.新增或删除如何用
1.pojo层的方法为：insertOrUpdate()
1.无d的情况：
@Test
public void testPojoInsertOrUpdate(){
User user = new User();
user.setName("ddd");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
user.insertOrUpdate();
}
2.测试结果
3.结论：没有ID就会新增
4.有ID的情况：
@Test
public void testPojoInsertOrUpdate(){
User user = new User();
user.setId(9L);
user.setName("xxx");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
user.insertOrUpdate();
}
5.结论：有ID就会更新
2.mapper层没有
3.service层的方法为：saveOrUpdate()
1.无d的情况：
@Test
public void testPojoInsertOrUpdate(){
User user = new User();
user.setName("eee");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
userService.saveOrUpdate(user);
}
2.有id的情况；
@Test
public void testPojoInsertOrUpdate(){
User user = new User();
user.setId(10L);
user.setName("gggg");
user.setPassword("123456");
user.setAge(30);
user.setCreateTime(new Timestamp(System.currentTimeMillis()));
user.setSex("男");
userService.saveOrUpdate(user);
}
3.结论：有id就会更新，没有id就会新增
5.分页查询
1.配置类
@Configuration
@MapperScan("scan.your.mapper.package")
public class MybatisPlusConfig {
@Bean
public MybatisPlusInterceptor mybatisPlusInterceptor() {
MybatisPlusInterceptor interceptor = new MybatisPlusInterceptor();
//如果配置多个插件,切记分页最后添加
interceptor.addInnerInterceptor(new PaginationInnerInterceptor(DbType.MYSQL));
//interceptor.addInnerInterceptor(new PaginationInnerInterceptor()); 如果有多数据源可以不配具体类型 否则都建议配上具体的DbType
return interceptor;
}
}
2.查询当前表数据
1.在代码中的用法
1.service层代码
@Test
public void testServicePage(){
// 第1页 每页3条数据
IPage<User> userIPage = new Page<>(1,3);
IPage<User> pageData = userService.page(userIPage);
// 结果数据
System.out.println(pageData.getRecords());
// 当前页
System.out.println(pageData.getCurrent());
// 当前页总数
System.out.println(pageData.getSize());
// 总数
System.out.println(pageData.getTotal());
}
2.mapper层代码
@Test
public void testMapperPage(){
// 第1页 每页3条数据
IPage<User> userIPage = new Page<>(1,3);
IPage<User> pageData = userMapper.selectPage(userIPage,null);
// 结果数据
System.out.println(pageData.getRecords());
// 当前页
System.out.println(pageData.getCurrent());
// 当前页总数
System.out.println(pageData.getSize());
// 总数
System.out.println(pageData.getTotal());
}
3.pojo层代码
@Test
public void testPojoPage(){
// 第1页 每页3条数据
IPage<User> userIPage = new Page<>(1,3);
User user = new User();
IPage<User> pageData = user.selectPage(userIPage,null);
// 结果数据
System.out.println(pageData.getRecords());
// 当前页
System.out.println(pageData.getCurrent());
// 当前页总数
System.out.println(pageData.getSize());
// 总数
System.out.println(pageData.getTotal());
}
2.xml文件中的使用
1.在UserMapper中定义接口
IPage<User> findByPage(IPage<User> page);
2.xml文件配置
<select id="findByPage" resultType="com.andy.pojo.User">
select * from t_user where is_del = 0
select>
3.测试代码
@Test
public void testMapperPage(){
IPage<User> userIPage = new Page<>(1,3);
// 第1页 每页3条数据
IPage<User> pageData = userMapper.findByPage(userIPage);
// 结果数据
System.out.println(pageData.getRecords());
// 当前页
System.out.println(pageData.getCurrent());
// 当前页总数
System.out.println(pageData.getSize());
// 总数
System.out.println(pageData.getTotal());
}