# mp-extra

**Repository Path**: github-26359270/mp-extra

## Basic Information

- **Project Name**: mp-extra
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Apache-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 5
- **Forks**: 0
- **Created**: 2021-03-11
- **Last Updated**: 2022-08-12

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# mp-extra
this is a great tools to improve mybatis plus,with this tools ,  you can auto select from many tables from database at one times without other sql

> 项目中有sql文件  resources/data.sql

#### 添加依赖，已经发布到中央仓库了，可以直接使用：

```xml
<dependency>
    <groupId>top.lww0511</groupId>
    <artifactId>mp-extra</artifactId>
    <version>1.0.1</version>
</dependency>
```

#### 在启动类上添加注解
`@EnableMpExtra`

#### 配置拦截器

因为一般项目都会配置自己的`MybatisConfiguration`，我在这里配置后，打包，然后被引入，是无法生效的。

所以就想了一种折中的方法。

以前`MybatisConfiguration`是通过`new`出来的，现在通过`MybatisExtraConfig.getMPConfig();`来获取，这样获取到的`MybatisConfiguration`就已经添加好了拦截器。

完整`Mybatis-Plus`配置类例子，注意第43行:

```java
@Slf4j
@Configuration
@MapperScan(basePackages = "com.ler.demo.mapper", sqlSessionTemplateRef = "sqlSessionTemplate")
public class MybatisConfig {

    private static final String BASE_PACKAGE = "com.ler.demo.";

    @Bean("dataSource")
    public DataSource dataSource() {
        try {
            DruidDataSource dataSource = new DruidDataSource();
            dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");
            dataSource.setUrl("jdbc:mysql://localhost/mp-extra?useUnicode=true&useSSL=false&characterEncoding=utf8&serverTimezone=Asia/Shanghai");
            dataSource.setUsername("root");
            dataSource.setPassword("adminadmin");

            dataSource.setInitialSize(1);
            dataSource.setMaxActive(20);
            dataSource.setMinIdle(1);
            dataSource.setMaxWait(60_000);
            dataSource.setPoolPreparedStatements(true);
            dataSource.setMaxPoolPreparedStatementPerConnectionSize(20);
            dataSource.setTimeBetweenEvictionRunsMillis(60_000);
            dataSource.setMinEvictableIdleTimeMillis(300_000);
            dataSource.setValidationQuery("SELECT 1");
            return dataSource;
        } catch (Throwable throwable) {
            log.error("ex caught", throwable);
            throw new RuntimeException();
        }
    }

    @Bean(name = "sqlSessionFactory")
    public SqlSessionFactory sqlSessionFactory(@Qualifier("dataSource") DataSource dataSource) throws Exception {
        MybatisSqlSessionFactoryBean factoryBean = new MybatisSqlSessionFactoryBean();
        factoryBean.setDataSource(dataSource);
        factoryBean.setVfs(SpringBootVFS.class);
        factoryBean.setTypeAliasesPackage(BASE_PACKAGE + "entity");

        Resource[] mapperResources = new PathMatchingResourcePatternResolver().getResources("classpath*:mapper/*.xml");
        factoryBean.setMapperLocations(mapperResources);

        MybatisConfiguration configuration = MybatisExtraConfig.getMPConfig();
        configuration.setDefaultScriptingLanguage(MybatisXMLLanguageDriver.class);
        configuration.setJdbcTypeForNull(JdbcType.NULL);
        configuration.setMapUnderscoreToCamelCase(true);
        configuration.addInterceptor(new SqlExplainInterceptor());
        configuration.setUseGeneratedKeys(true);
        factoryBean.setConfiguration(configuration);
        return factoryBean.getObject();
    }

    @Bean(name = "sqlSessionTemplate")
    public SqlSessionTemplate sqlSessionTemplate(@Qualifier("sqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

    @Bean(name = "transactionManager")
    public PlatformTransactionManager platformTransactionManager(@Qualifier("dataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "transactionTemplate")
    public TransactionTemplate transactionTemplate(@Qualifier("transactionManager") PlatformTransactionManager transactionManager) {
        return new TransactionTemplate(transactionManager);
    }

}
```

#### 在实体类上建立关系

```java
@Data
@EqualsAndHashCode(callSuper = false)
@Accessors(chain = true)
@ApiModel(value = "UserAccount对象", description = "用户相关")
public class UserAccount extends Model<UserAccount> {

    private static final long serialVersionUID = 1L;

    @ApiModelProperty(value = "id")
    @TableId(value = "id", type = IdType.AUTO)
    private Long id;

    @ApiModelProperty(value = "昵称")
    private String nickName;

    @TableField(exist = false)
    //把id的值 作为userId  在 UserAddressMapper中 查询
    @One2One(self = "id", as = "user_id", mapper = UserAddressMapper.class)
    private UserAddress address;

    @TableField(exist = false)
    @One2Many(self = "id", as = "user_id", mapper = UserHobbyMapper.class)
    private List<UserHobby> hobbies;

    @TableField(exist = false)
    @Many2Many(self = "id", leftMid = "user_id", rightMid = "class_id", origin = "id"
            , midMapper = UserMidClassMapper.class, mapper = UserClassMapper.class)
    private List<UserClass> classes;

    @Override
    protected Serializable pkVal() {
        return this.id;
    }

}
```

主要是那几个注解。对了还要加`@TableField(exist = false)`，不然会报错。

#### 测试接口

```java
@Slf4j
@RestController
@RequestMapping("/user")
@Api(value = "/user", description = "用户")
public class UserAccountController {

    @Resource
    private UserAccountService userAccountService;

    @Resource
    private UserAccountMapper userAccountMapper;

    @ApiOperation("查询一个")
    @ApiImplicitParams({
            @ApiImplicitParam(name = "", value = "", required = true),
    })
    @GetMapping(value = "/one", name = "查询一个")
    public HttpResult one() {
        //service
        UserAccount account = userAccountService.getById(1L);
        //mapper
        // UserAccount account = userAccountMapper.selectById(1L);
        //AR模式
        // UserAccount account = new UserAccount();
        // account.setId(1L);
        // account = account.selectById();
        return HttpResult.success(account);
    }
}
```

接口非常简单，调用内置的`getById`，可是却查出了所有相关的数据，这都是因为配置的那些注解。

<img src="https://www.yunask.cn/images/mpe/1.jpg"  width=100%>

可以看到其实发送了好几条`SQL`。第一条是`userAccountService.getById(1L)`，后面几条都是自动发送的。

<img src="https://www.yunask.cn/images/mpe/2.jpg"  width=100%>

大家觉得好用可以点个`Star`。欢迎大家一起来贡献。

GitHub: https://github.com/LerDer/mp-extra

示例 https://gitee.com/github-26359270/mp-extra-demo

最后欢迎大家关注我的公众号，共同学习，一起进步。加油🤣

<img src="https://www.yunask.cn/images/minap/q.jpg"  width=50%>