pom.xml

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.2.0</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
        <!-- https://mvnrepository.com/artifact/p6spy/p6spy -->
        <dependency>
            <groupId>p6spy</groupId>
            <artifactId>p6spy</artifactId>
            <version>3.8.0</version>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
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        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.49</version>
            <scope>test</scope>
        </dependency>
        <!-- for testing -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

application.yml

spring:
  datasource:
    driver-class-name: com.p6spy.engine.spy.P6SpyDriver
    url: jdbc:p6spy:h2:tcp://192.168.180.115:19200/~/mem/test
    username: root
    password: test

Mapper及注入器

public class CustomizeSuperMapperSqlInjector extends DefaultSqlInjector {
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    /**
     * 如果只需增加方法，保留MP自带方法
     * 可以super.getMethodList() 再add
     * @return
     */
    @Override
    public List<AbstractMethod> getMethodList(Class<?> mapperClass) {
        List<AbstractMethod> methodList = super.getMethodList(mapperClass);
        methodList.add(new FindOne());
        return methodList;
    }
}
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public interface MySuperMapper<T> extends Mapper {
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    public T findOne(Object id);
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}
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public interface UserMapper extends MySuperMapper<User> {
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}

配置类

@Configuration
@MapperScan("com.mp.basemapper.mapper")
public class MybatisPlusConfig {
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    @Bean
    public CustomizeSuperMapperSqlInjector customizeSuperMapperSqlInjector(){
        return new CustomizeSuperMapperSqlInjector();
    }
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}

实体类

@Data
@Accessors(chain = true)
public class User {
    private Long id;
    private String name;
    private Integer age;
    private String email;
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    private Integer version;
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    private Integer deleted;
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    private Timestamp createTime;
}

方法

public class FindOne extends AbstractMethod {
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    @Override
    public MappedStatement injectMappedStatement(Class<?> mapperClass, Class<?> modelClass, TableInfo tableInfo) {
        /* 执行 SQL ，动态 SQL 参考类 SqlMethod */
        String sql = "select * from "   tableInfo.getTableName()
                  " where "   tableInfo.getKeyColumn()   "=#{"   tableInfo.getKeyProperty()   "}";
        /* mapper 接口方法名一致 */
        String method = "findOne";
        SqlSource sqlSource = languageDriver.createSqlSource(configuration, sql, modelClass);
        return addSelectMappedStatementForTable(mapperClass, method, sqlSource, tableInfo);
    }
}

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测试类

@SpringBootTest
class BasemapperApplicationTests {
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    @Autowired
    UserMapper userMapper;
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    @Test
    public void test() {
        User user = userMapper.findOne(1L);
        System.out.println(user);
    }
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}

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测试结果

2019-10-31 11:59:30.159  INFO 828 --- [           main] com.zaxxer.hikari.HikariDataSource       : HikariPool-1 - Start completed.
 Consume Time：4 ms 2019-10-31 11:59:30
 Execute SQL：select * from user where id=1