SpringBoot整合Mybatisplus3.x之CRUD

Posted 2020-12-01 天宇轩-王

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pom.xml

 1 <dependencies>
 2         <dependency>
 3             <groupId>org.springframework.boot</groupId>
 4             <artifactId>spring-boot-starter</artifactId>
 5         </dependency>
 6         <dependency>
 7             <groupId>org.springframework.boot</groupId>
 8             <artifactId>spring-boot-starter-test</artifactId>
 9             <scope>test</scope>
10         </dependency>
11         <dependency>
12             <groupId>org.projectlombok</groupId>
13             <artifactId>lombok</artifactId>
14             <optional>true</optional>
15         </dependency>
16         <dependency>
17             <groupId>com.baomidou</groupId>
18             <artifactId>mybatis-plus-boot-starter</artifactId>
19             <version>3.2.0</version>
20         </dependency>
21         <dependency>
22             <groupId>com.h2database</groupId>
23             <artifactId>h2</artifactId>
24             <scope>runtime</scope>
25         </dependency>
26         <dependency>
27             <groupId>p6spy</groupId>
28             <artifactId>p6spy</artifactId>
29         </dependency>
30     </dependencies>
31 ?
32     <build>
33         <plugins>
34             <plugin>
35                 <groupId>org.springframework.boot</groupId>
36                 <artifactId>spring-boot-maven-plugin</artifactId>
37             </plugin>
38         </plugins>
39     </build>

application.yml

# DataSource Config
spring:
  datasource:
    driver-class-name: org.h2.Driver
    url: jdbc:h2:tcp://192.168.180.115:19200/~/mem/test
    username: root
    password: test
?
# Logger Config
logging:
  level:
    com.mp.crud: debug

dao层

public interface UserMapper extends BaseMapper<User> {
?
}

实体类

 1 @Data
 2 @Accessors(chain = true)
 3 @TableName("user")
 4 public class User {
 5 ?
 6     private Long id;
 7     private String name;
 8     private Integer age;
 9     private String email;
10 ?
11     @TableField(exist = false)
12     private Integer count;
13 }

配置类

1 @Configuration
2 @MapperScan("com.mp.crud.mapper")
3 public class MybatisPlusConfig {
4 ?
5 }
6 ?

测试类

  1 @SpringBootTest
  2 @RunWith(SpringRunner.class)
  3 class CrudApplicationTests {
  4 ?
  5     @Resource
  6     private UserMapper mapper;
  7 ?
  8     @Test
  9     public void aInsert() {
 10         User user = new User();
 11         user.setName("小羊");
 12         user.setAge(3);
 13         user.setEmail("abc@mp.com");
 14         assertThat(mapper.insert(user)).isGreaterThan(0);
 15         // 成功直接拿会写的 ID
 16         assertThat(user.getId()).isNotNull();
 17     }
 18 ?
 19 ?
 20     @Test
 21     public void bDelete() {
 22         assertThat(mapper.deleteById(3L)).isGreaterThan(0);
 23         assertThat(mapper.delete(new QueryWrapper<User>()
 24                 .lambda().eq(User::getName, "Sandy"))).isGreaterThan(0);
 25     }
 26 ?
 27 ?
 28     @Test
 29     public void cUpdate() {
 30         //UPDATE user SET email=? WHERE id=?
 31         assertThat(mapper.updateById(new User().setId(1L).setEmail("ab@c.c"))).isGreaterThan(0);
 32         //UPDATE user SET name=?, age=? WHERE (id = ?)
 33         assertThat(
 34                 mapper.update(
 35                         new User().setName("mp"),
 36                         Wrappers.<User>lambdaUpdate()
 37                                 .set(User::getAge, 3)
 38                                 .eq(User::getId, 2)
 39                 )
 40         ).isGreaterThan(0);
 41         User user = mapper.selectById(2);
 42         assertThat(user.getAge()).isEqualTo(3);
 43         assertThat(user.getName()).isEqualTo("mp");
 44 ?
 45         mapper.update(
 46                 null,
 47                 Wrappers.<User>lambdaUpdate().set(User::getEmail, null).eq(User::getId, 2)
 48         );
 49         assertThat(mapper.selectById(1).getEmail()).isEqualTo("ab@c.c");
 50         user = mapper.selectById(2);
 51         assertThat(user.getEmail()).isNull();
 52         assertThat(user.getName()).isEqualTo("mp");
 53 ?
 54         mapper.update(
 55                 new User().setEmail("miemie@baomidou.com"),
 56                 new QueryWrapper<User>()
 57                         .lambda().eq(User::getId, 2)
 58         );
 59         user = mapper.selectById(2);
 60         assertThat(user.getEmail()).isEqualTo("miemie@baomidou.com");
 61 ?
 62         mapper.update(
 63                 new User().setEmail("miemie2@baomidou.com"),
 64                 Wrappers.<User>lambdaUpdate()
 65                         .set(User::getAge, null)
 66                         .eq(User::getId, 2)
 67         );
 68         user = mapper.selectById(2);
 69         assertThat(user.getEmail()).isEqualTo("miemie2@baomidou.com");
 70         assertThat(user.getAge()).isNull();
 71     }
 72 ?
 73 ?
 74     @Test
 75     public void dSelect() {
 76         mapper.insert(
 77                 new User().setId(10086L)
 78                         .setName("miemie")
 79                         .setEmail("miemie@baomidou.com")
 80                         .setAge(3));
 81         assertThat(mapper.selectById(10086L).getEmail()).isEqualTo("miemie@baomidou.com");
 82         User user = mapper.selectOne(new QueryWrapper<User>().lambda().eq(User::getId, 10086));
 83         assertThat(user.getName()).isEqualTo("miemie");
 84         assertThat(user.getAge()).isEqualTo(3);
 85 ?
 86         List<User> users = mapper.selectList(Wrappers.<User>lambdaQuery().select(User::getId));
 87         System.out.println(users);
 88 ?
 89         mapper.selectList(Wrappers.<User>lambdaQuery().select(User::getId))
 90                 .forEach(x -> {
 91                     assertThat(x.getId()).isNotNull();
 92                     assertThat(x.getEmail()).isNull();
 93                     assertThat(x.getName()).isNull();
 94                     assertThat(x.getAge()).isNull();
 95                 });
 96         mapper.selectList(new QueryWrapper<User>().select("id", "name"))
 97                 .forEach(x -> {
 98                     assertThat(x.getId()).isNotNull();
 99                     assertThat(x.getEmail()).isNull();
100                     assertThat(x.getName()).isNotNull();
101                     assertThat(x.getAge()).isNull();
102                 });
103     }
104 ?
105     @Test
106     public void orderBy() {
107         List<User> users = mapper.selectList(Wrappers.<User>query().orderByAsc("age"));
108         System.out.println(users);
109         //assertThat(users).isNotEmpty();
110     }
111 ?
112     @Test
113     public void selectMaps() {
114         List<Map<String, Object>> mapList = mapper.selectMaps(Wrappers.<User>query().orderByAsc("age"));
115         assertThat(mapList).isNotEmpty();
116         assertThat(mapList.get(0)).isNotEmpty();
117         //{ID=1189005852158324737, EMAIL=abc@mp.com, NAME=小羊, AGE=3}
118         System.out.println(mapList.get(0));
119     }
120 ?
121     @Test
122     public void selectMapsPage() {
123         IPage<Map<String, Object>> page = mapper.selectMapsPage(new Page<>(1, 5), Wrappers.<User>query().orderByAsc("age"));
124         assertThat(page).isNotNull();
125         assertThat(page.getRecords()).isNotEmpty();
126         assertThat(page.getRecords().get(0)).isNotEmpty();
127     }
128 ?
129     @Test
130     public void orderByLambda() {
131         //SELECT id,name,email,age FROM user ORDER BY age ASC
132         List<User> users = mapper.selectList(Wrappers.<User>lambdaQuery().orderByAsc(User::getAge));
133         List<User>  users1 = mapper.selectList(Wrappers.<User>query().orderByAsc("age"));
134         System.out.println(users1);
135         //assertThat(users).isNotEmpty();
136     }
137 ?
138     @Test
139     public void testSelectMaxId() {
140         // SELECT max(id) as id FROM user
141         QueryWrapper<User> wrapper = new QueryWrapper<>();
142         wrapper.select("max(id) as id");
143         //User(id=1189005852158324737, name=null, age=null, email=null, count=null)
144         User user = mapper.selectOne(wrapper);
145         System.out.println(user);
146         System.out.println("maxId=" + user.getId());
147         List<User> users = mapper.selectList(Wrappers.<User>lambdaQuery().orderByDesc(User::getId));
148         Assert.assertEquals(user.getId().longValue(), users.get(0).getId().longValue());
149     }
150 ?
151     @Test
152     public void testGroup() {
153         QueryWrapper<User> wrapper = new QueryWrapper<>();
154         wrapper.select("age, count(*)")
155                 .groupBy("age");
156         List<Map<String, Object>> maplist = mapper.selectMaps(wrapper);
157         for (Map<String, Object> mp : maplist) {
158             System.out.println(mp);
159         }
160         /**
161          * lambdaQueryWrapper groupBy orderBy
162          */
163         LambdaQueryWrapper<User> lambdaQueryWrapper = new QueryWrapper<User>().lambda()
164                 .select(User::getAge)
165                 .groupBy(User::getAge)
166                 .orderByAsc(User::getAge);
167         for (User user : mapper.selectList(lambdaQueryWrapper)) {
168             System.out.println(user);
169         }
170     }
171 ?
172     @Test
173     public void testTableFieldExistFalse(){
174         QueryWrapper<User> wrapper = new QueryWrapper<>();
175         wrapper.select("age, count(age) as count")
176                 .groupBy("age");
177         List<User> list = mapper.selectList(wrapper);
178         list.forEach(System.out::println);
179         list.forEach(x->{
180             Assert.assertNull(x.getId());
181             Assert.assertNotNull(x.getAge());
182             Assert.assertNotNull(x.getCount());
183         });
184         mapper.insert(
185                 new User().setId(10088L)
186                         .setName("miemie")
187                         .setEmail("miemie@baomidou.com")
188                         .setAge(3));
189         User miemie = mapper.selectById(10088L);
190         Assert.assertNotNull(miemie);
191 ?
192     }
193 ?
194 }
195 ?

测试结果（我处只运行了部分的测试方法）

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