Compared with the commonly used mybatis, mybatisPlus can help us focus more on business development and reduce the coding of sql files. Let's use SpringBoot + mybatisPlus build a project. 1. Summary of problems encountered during the construction process
(1) Start-up error report
Add dependency
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.1.tmp</version>
</dependency>
Because of the reference relationship, it is mandatory to upgrade the mybatis-spring-boot-starter version number to 2.0.0 or higher.
<dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.0.1</version> </dependency>
(2) Service can have a method of operating the database by inheriting IService<T>
Ways to realize the query 1,
userService.getOne(Wrappers.<User>lambdaQuery().eq(false, User :: getId, 3L).orderByDesc(User::getId).last("limit 1"));
Ways to realize the query 2,
QueryWrapper<User> wrapper = new QueryWrapper<>();
wrapper.eq("name", "Save1").or().eq("phone_number", "17300000001").orderByDesc("id");
(3) There are many pitfalls in the mybatisPlus method. For example, the getOne method returns a single model, but sql does not add limit 1
So it needs to be spelled in the back.last("limit 1"));
Therefore, there may be many problems in use, it is recommended to look at the method implementation of IService first
## spring-boot-demo-mybatis-plus
#pom
<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>com.juejueguai</groupId>
<artifactId>spring-boot-demo</artifactId>
<version>1.0-SNAPSHOT</version>
</parent>
<groupId>com.example</groupId>
<artifactId>spring-boot-demo-mybatis-plus</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>spring-boot-demo-mybatis-plus</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.1.tmp</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
#yml
spring:
datasource:
url: jdbc:mysql://localhost:3306/spring_boot_test?useUnicode=true&characterEncoding=UTF-8&useSSL=false&autoReconnect=true&failOverReadOnly=false&serverTimezone=GMT%2B8
username: root
password: root
driver-class-name: com.mysql.jdbc.Driver
type: com.zaxxer.hikari.HikariDataSource
initialization-mode: always
continue-on-error: true
hikari:
minimum-idle: 5
connection-test-query: SELECT 1 FROM DUAL
maximum-pool-size: 20
auto-commit: true
idle-timeout: 30000
pool-name: SpringBootDemoHikariCP
max-lifetime: 60000
connection-timeout: 30000
logging:
level:
com.juejueguai: debug
com..juejueguai.springbootdemomybatisplus.mapper: trace
mybatis-plus:
mapper-locations: classpath:mappers/*.xml
#Entity scanning, multiple packages separated by commas or semicolons
typeAliasesPackage: com.juejueguai.springbootdemomybatisplus.entity
global-config:
# Database related configuration
db-config:
#Primary key type AUTO: "Database ID self-increment", INPUT: "User input ID", ID_WORKER: "Globally unique ID (number type unique ID)", UUID: "Globally unique ID UUID";
id-type: auto
#Field strategy IGNORED: "ignore judgment", NOT_NULL: "non-NULL judgment"), NOT_EMPTY: "non-null judgment"
field-strategy: not_empty
#Hump underline conversion
table-underline: true
#Whether to enable capital naming, not enabled by default
#capital-mode: true
#Logical delete configuration
#logic-delete-value: 1
#logic-not-delete-value: 0
db-type: mysql
#Refresh mapper debugging artifact
refresh: true
#Primary arrangement
configuration:
map-underscore-to-camel-case: true
cache-enabled: true
server:
port: 9004
# sql file
/*
Navicat MySQL Data Transfer
Source Server: local database
Source Server Version : 50549
Source Host : localhost:3306
Source Database : spring_boot_test
Target Server Type : MYSQL
Target Server Version : 50549
File Encoding : 65001
Date: 2020-07-17 16:16:48
*/
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for orm_role
-- ----------------------------
DROP TABLE IF EXISTS `orm_role`;
CREATE TABLE `orm_role` (
`id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键',
`name` varchar(32) NOT NULL COMMENT'role name',
PRIMARY KEY (`id`),
UNIQUE KEY `name` (`name`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8 COMMENT='Spring Boot Demo Orm series example table';
-- ----------------------------
-- Records of orm_role
-- ----------------------------
INSERT INTO `orm_role` VALUES ('2','ordinary user');
INSERT INTO `orm_role` VALUES ('1','Administrator');
/*
Navicat MySQL Data Transfer
Source Server: local database
Source Server Version : 50549
Source Host : localhost:3306
Source Database : spring_boot_test
Target Server Type : MYSQL
Target Server Version : 50549
File Encoding : 65001
Date: 2020-07-17 16:17:23
*/
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for orm_user
-- ----------------------------
DROP TABLE IF EXISTS `orm_user`;
CREATE TABLE `orm_user` (
`id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键',
`name` varchar(32) NOT NULL COMMENT'Username',
`password` varchar(32) NOT NULL COMMENT'encrypted password',
`salt` varchar(32) NOT NULL COMMENT'Salt used for encryption',
`email` varchar(32) NOT NULL COMMENT'mailbox',
`phone_number` varchar(15) NOT NULL COMMENT'phone number',
`status` int(2) NOT NULL DEFAULT '1' COMMENT'status, -1: logical deletion, 0: disable, 1: enable',
`create_time` datetime DEFAULT NULL COMMENT'create time',
`last_login_time` datetime DEFAULT NULL COMMENT'Last login time',
`last_update_time` datetime DEFAULT NULL COMMENT'Last update time',
PRIMARY KEY (`id`),
UNIQUE KEY `name` (`name`),
UNIQUE KEY `email` (`email`),
UNIQUE KEY `phone_number` (`phone_number`)
) ENGINE=InnoDB AUTO_INCREMENT=36 DEFAULT CHARSET=utf8 COMMENT='Spring Boot Demo Orm series example table';
-- ----------------------------
-- Records of orm_user
-- ----------------------------
INSERT INTO `orm_user` VALUES ('2', 'user_2', '6c6bf02c8d5d3d128f34b1700cb1e32c', 'fcbdd0e8a9404a5585ea4e01d0e4d7a0', '[email protected]', '17300000002', '1', null, null, null);
INSERT INTO `orm_user` VALUES ('3','MybatisPlus modify name', '123456456', '456','[email protected]', '17300000003', '1', '2020-07-17 14:52 :15', '2020-07-17 14:52:15', '2020-07-17 15:05:46');
INSERT INTO `orm_user` VALUES ('4', 'testSave4', '123456456', '456', '[email protected]', '17300000004', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('5', 'testSave5', '123456456', '456', '[email protected]', '17300000005', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('6', 'testSave6', '123456456', '456', '[email protected]', '17300000006', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('7', 'testSave7', '123456456', '456', '[email protected]', '17300000007', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('8', 'testSave8', '123456456', '456', '[email protected]', '17300000008', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('9', 'testSave9', '123456456', '456', '[email protected]', '17300000009', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('10', 'testSave10', '123456456', '456', '[email protected]', '173000000010', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('11', 'testSave11', '123456456', '456', '[email protected]', '173000000011', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('12', 'testSave12', '123456456', '456', '[email protected]', '173000000012', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('13', 'testSave13', '123456456', '456', '[email protected]', '173000000013', '1', '2020-07-17 14:52:51', '2020-07-17 14:52:51', '2020-07-17 14:52:51');
INSERT INTO `orm_user` VALUES ('24', 'testSave14', '123456456', '456', '[email protected]', '173000000014', '1', '2020-07-17 15:16:00', '2020-07-17 15:16:00', '2020-07-17 15:16:00');
INSERT INTO `orm_user` VALUES ('25', 'testSave15', '123456456', '456', '[email protected]', '173000000015', '1', '2020-07-17 15:16:00', '2020-07-17 15:16:00', '2020-07-17 15:16:00');
INSERT INTO `orm_user` VALUES ('26', 'testSave16', '123456456', '456', '[email protected]', '173000000016', '1', '2020-07-17 15:16:00', '2020-07-17 15:16:00', '2020-07-17 15:16:00');
INSERT INTO `orm_user` VALUES ('27', 'testSave17', '123456456', '456', '[email protected]', '173000000017', '1', '2020-07-17 15:16:00', '2020-07-17 15:16:00', '2020-07-17 15:16:00');
INSERT INTO `orm_user` VALUES ('28', 'testSave18', '123456456', '456', '[email protected]', '173000000018', '1', '2020-07-17 15:16:00', '2020-07-17 15:16:00', '2020-07-17 15:16:00');
INSERT INTO `orm_user` VALUES ('29', 'testSave19', '123456456', '456', '[email protected]', '173000000019', '1', '2020-07-17 15:16:00', '2020-07-17 15:16:00', '2020-07-17 15:16:00');
# config file
@ Slf4j
@Component
public class CommonFieldHandler implements MetaObjectHandler {
@Override
public void insertFill(MetaObject metaObject) {
log.info("start insert fill ....");
this.setFieldValByName("createTime", new Date(), metaObject);
this.setFieldValByName("lastUpdateTime", new Date(), metaObject);
}
@Override
public void updateFill(MetaObject metaObject) {
log.info("start update fill ....");
this.setFieldValByName("lastUpdateTime", new Date(), metaObject);
}
}
@Configuration
@MapperScan(basePackages = {"com.juejueguai.springbootdemomybatisplus.mapper"})
@EnableTransactionManagement
public class MybatisPlusConfig {
@Bean
public PaginationInterceptor paginationInterceptor () {
return new PaginationInterceptor();
}
}
# entity
@Data
@NoArgsConstructor
@AllArgsConstructor
@Builder
@TableName("orm_user")
public class User implements Serializable {
private static final long serialVersionUID = -1840831686851699943L;
/**
* Primary key
*/
private Long id;
/**
* username
*/
private String name;
/**
* Encrypted password
*/
private String password;
/**
* The salt used for encryption
*/
private String salt;
/**
* Email
*/
private String email;
/**
* mobile phone number
*/
private String phoneNumber;
/**
* Status, -1: logical deletion, 0: disable, 1: enable
*/
private Integer status;
/**
* Creation time
*/
@TableField(fill = INSERT)
private Date createTime;
/**
* Last Login Time
*/
private Date lastLoginTime;
/**
* Last update time
*/
@TableField(fill = INSERT_UPDATE)
private Date lastUpdateTime;
}
# mapper
@Component
public interface UserMapper extends BaseMapper<User> {
}
# service
public interface UserService extends IService<User> {
}
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {
}
# test
@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringBootDemoMybatisPlusApplicationTests {
@Test
public void contextLoads() {
}
}
@ Slf4j
public class UserServiceTest extends SpringBootDemoMybatisPlusApplicationTests {
@Autowired
private UserService userService;
/**
* Test Mybatis-Plus added
*/
@Test
public void testSave() {
String salt = "456";
User testSave3 = User.builder().name("testSave").password("123456" + salt).salt(salt).email("[email protected]").phoneNumber("17300000003").status(1).lastLoginTime(new Date()).build();
boolean save = userService.save(testSave3);
Assert.assertTrue(save);
log.debug("【测试id回显#testSave3.getId()】= {}", testSave3.getId());
}
/**
* Test Mybatis-Plus batch addition
*/
@Test
public void testSaveList() {
List<User> userList = Lists.newArrayList();
for (int i = 14; i < 20; i++) {
String salt = "456";
User user = User.builder().name("testSave" + i).password("123456" + salt).salt(salt).email("testSave" + i + "@xkcoding.com").phoneNumber("1730000000" + i).status(1).lastLoginTime(new Date()).build();
userList.add(user);
}
boolean batch = userService.saveBatch(userList);
Assert.assertTrue(batch);
List<Long> ids = userList.stream().map(User::getId).collect(Collectors.toList());
log.debug("【userList#ids】= {}", ids);
}
/**
* Test Mybatis-Plus delete
*/
@Test
public void testDelete() {
boolean remove = userService.removeById(1L);
User byId = userService.getById(1L);
Assert.assertNull(byId);
}
/**
* Test Mybatis-Plus modification
*/
@Test
public void testUpdate() {
User user = userService.getById(3L);
user.setName("MybatisPlus modify name");
boolean b = userService.updateById(user);
Assert.assertTrue(b);
User update = userService.getById(3L);
Assert.assertEquals("MybatisPlus modify name", update.getName());
log.debug("【update】= {}", update);
}
/**
* Test Mybatis-Plus to query a single
*/
@Test
public void testQueryOne() {
User user = userService.getOne(Wrappers.<User>lambdaQuery().eq(false, User :: getId, 3L).orderByDesc(User::getId).last("limit 1"));
Assert.assertNotNull(user);
log.debug("【user】= {}", user);
}
/**
* Test Mybatis-Plus to check all
*/
@Test
public void testQueryAll() {
List<User> list = userService.list(new QueryWrapper<>());
Assert.assertTrue(!CollectionUtils.isEmpty(list));
log.debug("【list】= {}", list);
}
/**
* Test Mybatis-Plus paging sort query
*/
@Test
public void testQueryByPageAndSort() {
initData ();
int count = userService.count(new QueryWrapper<>());
Page<User> userPage = new Page<>(1, 5);
userPage.setDesc("id");
IPage<User> page = userService.page(userPage, new QueryWrapper<>());
Assert.assertEquals(5, page.getSize());
Assert.assertEquals(count, page.getTotal());
log.debug("【page.getRecords()】= {}", page.getRecords());
}
/**
* Test Mybatis-Plus custom query
*/
@Test
public void testQueryByCondition() {
QueryWrapper<User> wrapper = new QueryWrapper<>();
wrapper.like("name", "Save1").or().eq("phone_number", "17300000001").orderByDesc("id");
userService.getOne(wrapper);
int count = userService.count(wrapper);
Page<User> userPage = new Page<>(1, 3);
IPage<User> page = userService.page(userPage, wrapper);
Assert.assertEquals(3, page.getSize());
Assert.assertEquals(count, page.getTotal());
log.debug("【page.getRecords()】= {}", page.getRecords());
}
/**
* Initialization data
*/
private void initData() {
testSaveList ();
}
}
Source code path: https://github.com/juejuedog/SpringBootDemo.git