SpringBoot2.1.9 Mybatis由于@Mapper注解多数据源配置不生效问题

你的名字 2023-07-24 13:24 3阅读 0赞

### 一、场景复现 ###

**（1）项目**

**目录**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L21vYWt1bg_size_16_color_FFFFFF_t_70][]

**配置文件**

spring:
      application:
        name: multi-datasource
      profiles:
        active: dev1
      datasource:
        type: com.alibaba.druid.pool.DruidDataSource
        driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://localhost:3306/base?autoReconnect=true&zeroDateTimeBehavior=convertToNull&characterEncoding=UTF-8
        username: root
        password: admin
    mybatis:
      mapper-locations: classpath*:mapper/base/*.xml
      type-aliases-package: com.mk.mybatis.multidatasource
      configuration:
        map-underscore-to-camel-case: true
    
    sys:
      one-mybatis:
        datasource:
          type: com.alibaba.druid.pool.DruidDataSource
          driver-class-name: com.mysql.jdbc.Driver
          url: jdbc:mysql://localhost:3306/man?autoReconnect=true&zeroDateTimeBehavior=convertToNull&characterEncoding=UTF-8
          username: root
          password: admin
        mybatis:
          mapper-locations: classpath*:mapper/one/*.xml
          type-aliases-package: com.mk.mybatis.multidatasource.one.entity
          configuration:
            map-underscore-to-camel-case: true
      two-mybatis:
        datasource:
          type: com.alibaba.druid.pool.DruidDataSource
          driver-class-name: com.mysql.jdbc.Driver
          url: jdbc:mysql://localhost:3306/person?autoReconnect=true&zeroDateTimeBehavior=convertToNull&characterEncoding=UTF-8
          username: root
          password: admin
        mybatis:
          mapper-locations: classpath*:mapper/two/*.xml
          type-aliases-package: com.mk.mybatis.multidatasource.two.entity
          configuration:
            map-underscore-to-camel-case: true
    
    server:
      port: 8080

**pom.xml**

<?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>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.9.RELEASE</version>
            <relativePath/>
        </parent>
        <groupId>com.mk.mybatis</groupId>
        <artifactId>multi-datasource</artifactId>
        <version>1.0-SNAPSHOT</version>
        <name>multi-datasource</name>
        <description>MybatisMultiDataSource</description>
    
        <properties>
            <java.version>1.8</java.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-devtools</artifactId>
                <scope>runtime</scope>
                <optional>true</optional>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <optional>true</optional>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.48</version>
            </dependency>
    
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>2.1.0</version>
            </dependency>
                    <dependency>
                        <groupId>com.alibaba</groupId>
                        <artifactId>druid</artifactId>
                        <version>1.1.20</version>
                    </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>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
                <version>2.1.9.RELEASE</version>
            </dependency>
            <dependency>
                <groupId>tk.mybatis</groupId>
                <artifactId>mapper-spring-boot-starter</artifactId>
                <version>2.1.5</version>
                <exclusions>
                    <exclusion>
                        <groupId>javax.persistence</groupId>
                        <artifactId>persistence-api</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>
        </dependencies>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
    
                <plugin>
                    <groupId>org.mybatis.generator</groupId>
                    <artifactId>mybatis-generator-maven-plugin</artifactId>
                    <version>1.3.7</version>
                    <dependencies>
                        <dependency>
                            <groupId>org.mybatis.generator</groupId>
                            <artifactId>mybatis-generator-core</artifactId>
                            <version>1.3.7</version>
                        </dependency>
                    </dependencies>
                    <configuration>
                        
                        <verbose>true</verbose>
                        
                        <overwrite>true</overwrite>
                        
                        <configurationFile>
                            generatorConfig1.xml
                        </configurationFile>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </project>

**继承mybatis生成器生成的dao类**

@Mapper
    public interface DaseDao extends IBaseDao {
    }

@Mapper
    public interface ManDao extends IManDao {
    }

@Mapper
    public interface PersonDao extends IPersonDao {
    }

**默认mybatis数据源配置**

@Configuration
    @MapperScan(value = "com.mk.mybatis.multidatasource.base.dao", sqlSessionTemplateRef = "baseSqlSessionTemplate")
    public class BaseMybatisConfig {
    
        @Primary
        @Bean
        @ConfigurationProperties(prefix = "spring.datasource")
        public DataSourceProperties baseDataSourceProperties() {
            return new DataSourceProperties();
        }
    
        @Primary
        @Bean("datasource")
        public DataSource baseDataSource(@Qualifier("baseDataSourceProperties") DataSourceProperties dataSourceProperties) {
    
            DataSource dataSource = dataSourceProperties.initializeDataSourceBuilder().build();
            return dataSource;
        }
    
    
        @Primary
        @Bean
        @ConfigurationProperties(prefix = "mybatis")
        public MybatisProperties baseMybatisProperties() {
            return new MybatisProperties();
        }
    
        @Primary
        @Bean
        public SqlSessionFactory baseSqlSessionFactory(@Qualifier("datasource") DataSource dataSource,
                                                       @Qualifier("baseMybatisProperties") MybatisProperties mybatisProperties) throws Exception {
            SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
            bean.setDataSource(dataSource);
            bean.setMapperLocations(mybatisProperties.resolveMapperLocations());
            bean.setTypeAliasesPackage(mybatisProperties.getTypeAliasesPackage());
            bean.setConfigurationProperties(mybatisProperties.getConfigurationProperties());
            bean.setConfiguration(mybatisProperties.getConfiguration());
            bean.setConfigLocation(Optional.ofNullable(mybatisProperties.getConfigLocation()).map(location -> {
                try {
                    ResourcePatternResolver resourceResolver = new PathMatchingResourcePatternResolver();
                    return resourceResolver.getResource(location);
                } catch (Exception var3) {
                    return null;
                }
            }).orElse(null));
    
            return bean.getObject();
        }
    
    
        @Primary
        @Bean
        public DataSourceTransactionManager transactionManager(@Qualifier("datasource") DataSource dataSource) {
    
            return new DataSourceTransactionManager(dataSource);
        }
    
        @Primary
        @Bean
        public SqlSessionTemplate baseSqlSessionTemplate(@Qualifier("baseSqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
            return new SqlSessionTemplate(sqlSessionFactory);
        }

**one mybatis数据源配置**

@Configuration
    @MapperScan(value = "com.mk.mybatis.multidatasource.one.dao", sqlSessionTemplateRef = "oneSqlSessionTemplate")
    @Slf4j
    public class OneMybatisConfig {
    
    
        @Bean
        @ConfigurationProperties(prefix = "sys.one-mybatis.datasource")
        public DataSourceProperties oneDataSourceProperties() {
            return new DataSourceProperties();
        }
    
    
        @Bean
        public DataSource oneDataSource(@Qualifier("oneDataSourceProperties") DataSourceProperties dataSourceProperties) {
    
            DataSource dataSource = dataSourceProperties.initializeDataSourceBuilder().build();
            return dataSource;
        }
    
        @Bean
        @ConfigurationProperties(prefix = "sys.one-mybatis.mybatis")
        public MybatisProperties oneMybatisProperties(){
            return new MybatisProperties();
        }
    
    
        @Bean
        public SqlSessionFactory oneSqlSessionFactory(@Qualifier("oneDataSource") DataSource dataSource,
                                                              @Qualifier("oneMybatisProperties")MybatisProperties mybatisProperties)throws Exception{
            SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
            bean.setDataSource(dataSource);
            bean.setMapperLocations(mybatisProperties.resolveMapperLocations());
            bean.setTypeAliasesPackage(mybatisProperties.getTypeAliasesPackage());
            bean.setConfigurationProperties(mybatisProperties.getConfigurationProperties());
            bean.setConfiguration(mybatisProperties.getConfiguration());
            bean.setConfigLocation(Optional.ofNullable(mybatisProperties.getConfigLocation()).map(location->{
                try {
                    ResourcePatternResolver resourceResolver = new PathMatchingResourcePatternResolver();
                    return resourceResolver.getResource(location);
                } catch (Exception var3) {
                    return null;
                }
            }).orElse(null));
    
            return bean.getObject();
        }
    
    
    
        @Bean
        public DataSourceTransactionManager oneTransactionManager(@Qualifier("oneDataSource") DataSource dataSource) {
    
            return new DataSourceTransactionManager(dataSource);
        }
    
    
        @Bean
        public SqlSessionTemplate oneSqlSessionTemplate(@Qualifier("oneSqlSessionFactory") SqlSessionFactory sqlSessionFactory){
            return new SqlSessionTemplate(sqlSessionFactory);
        }
    }

**two mybatis数据源配置**

@Configuration
    @MapperScan(value = "com.mk.mybatis.multidatasource.two.dao", sqlSessionTemplateRef = "twoSqlSessionTemplate")
    @Slf4j
    public class TwoMybatisConfig {
    
        @Bean
        @ConfigurationProperties(prefix = "sys.two-mybatis.datasource")
        public DataSourceProperties twoDataSourceProperties() {
            return new DataSourceProperties();
        }
    
        @Bean
        public DataSource twoDataSource(@Qualifier("twoDataSourceProperties") DataSourceProperties dataSourceProperties) {
            DataSource dataSource = dataSourceProperties.initializeDataSourceBuilder().build();
            return dataSource;
        }
    
        @Bean
        @ConfigurationProperties(prefix = "sys.two-mybatis.mybatis")
        public MybatisProperties twoMybatisProperties() {
            return new MybatisProperties();
        }
    
        @Bean
        public SqlSessionFactory twoSqlSessionFactory(@Qualifier("twoDataSource") DataSource dataSource,
                                                      @Qualifier("twoMybatisProperties") MybatisProperties mybatisProperties) throws Exception {
            SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
            bean.setDataSource(dataSource);
            bean.setMapperLocations(mybatisProperties.resolveMapperLocations());
            bean.setTypeAliasesPackage(mybatisProperties.getTypeAliasesPackage());
            bean.setConfigurationProperties(mybatisProperties.getConfigurationProperties());
            bean.setConfiguration(mybatisProperties.getConfiguration());
            bean.setConfigLocation(Optional.ofNullable(mybatisProperties.getConfigLocation()).map(location -> {
                try {
                    ResourcePatternResolver resourceResolver = new PathMatchingResourcePatternResolver();
                    return resourceResolver.getResource(location);
                } catch (Exception var3) {
                    return null;
                }
            }).orElse(null));
    
            return bean.getObject();
        }
    
        @Bean
        public DataSourceTransactionManager twoTransactionManager(@Qualifier("twoDataSource") DataSource dataSource) {
    
            return new DataSourceTransactionManager(dataSource);
        }
    
        @Bean
        public SqlSessionTemplate twoSqlSessionTemplate(@Qualifier("twoSqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
            return new SqlSessionTemplate(sqlSessionFactory);
        }
    }

**（2）测试类**

**BaseDao**

@Resource
        private DaseDao baseDao;
    
        @Test
        public void testBaseDao()  {
              System.out.println(baseDao.selectByPrimaryKey(1));
        }

输出

2020-05-04 21:03:21,174 DEBUG [main] 5363 com.mk.mybatis.multidatasource.base.base.dao.IBaseDao.selectByPrimaryKey[143]: ==>  Preparing: select id, `name` from base where id = ? 
    2020-05-04 21:03:21,205 DEBUG [main] 5394 com.mk.mybatis.multidatasource.base.base.dao.IBaseDao.selectByPrimaryKey[143]: ==> Parameters: 1(Integer)
    2020-05-04 21:03:21,221 DEBUG [main] 5410 com.mk.mybatis.multidatasource.base.base.dao.IBaseDao.selectByPrimaryKey[143]: <==      Total: 0
    null

debug看到的数据源

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L21vYWt1bg_size_16_color_FFFFFF_t_70 1][]

** PersonDao**

@Resource
        private PersonDao personDao;
    
        @Test
        public void testPersonDao() {
            System.out.println(personDao.selectByPrimaryKey(1));
        }

输出

org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.mk.mybatis.multidatasource.two.dao.PersonDao.selectByPrimaryKey
    
    	at org.apache.ibatis.binding.MapperMethod$SqlCommand.<init>(MapperMethod.java:235)
    	at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:53)
    	at org.apache.ibatis.binding.MapperProxy.lambda$cachedMapperMethod$0(MapperProxy.java:61)
    	at org.apache.ibatis.binding.MapperProxy$$Lambda$443/448131210.apply(Unknown Source)
    	at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1660)
    	at org.apache.ibatis.binding.MapperProxy.cachedMapperMethod(MapperProxy.java:61)
    	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:56)
    	at com.sun.proxy.$Proxy67.selectByPrimaryKey(Unknown Source)
    	at com.mk.mybatis.multidatasource.MultiDatasourceApplicationTests.testPersonDao(MultiDatasourceApplicationTests.java:34)
    	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    	at java.lang.reflect.Method.invoke(Method.java:497)
    	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    	at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74)
    	at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84)
    	at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
    	at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
    	at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
    	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251)
    	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
    	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
    	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

debug看到的数据源

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L21vYWt1bg_size_16_color_FFFFFF_t_70 2][]

**ManDao**

@Resource
        private ManDao manDao;
    
        @Test
        public void testManDao() {
            System.out.println(manDao.selectByPrimaryKey(1));
        }

输出：

org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): com.mk.mybatis.multidatasource.one.dao.ManDao.selectByPrimaryKey
    
    	at org.apache.ibatis.binding.MapperMethod$SqlCommand.<init>(MapperMethod.java:235)
    	at org.apache.ibatis.binding.MapperMethod.<init>(MapperMethod.java:53)
    	at org.apache.ibatis.binding.MapperProxy.lambda$cachedMapperMethod$0(MapperProxy.java:61)
    	at org.apache.ibatis.binding.MapperProxy$$Lambda$443/736951628.apply(Unknown Source)
    	at java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1660)
    	at org.apache.ibatis.binding.MapperProxy.cachedMapperMethod(MapperProxy.java:61)
    	at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:56)
    	at com.sun.proxy.$Proxy68.selectByPrimaryKey(Unknown Source)
    	at com.mk.mybatis.multidatasource.MultiDatasourceApplicationTests.testManDao(MultiDatasourceApplicationTests.java:40)
    	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    	at java.lang.reflect.Method.invoke(Method.java:497)
    	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    	at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74)
    	at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84)
    	at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
    	at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
    	at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
    	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251)
    	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
    	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
    	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
    	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)

debug看到的数据源

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L21vYWt1bg_size_16_color_FFFFFF_t_70 3][]

**（3）分析**

从上面的测试结果来看，多数据源配置不生效。

**然而去掉PersonDao和ManDao的@Mapper注解，多数据源配置就生效了**

PersonDao

//@Mapper
    public interface PersonDao extends IPersonDao {
    }

2020-05-04 21:26:18,477 DEBUG [main] 4644 com.mk.mybatis.multidatasource.two.base.dao.IPersonDao.selectByPrimaryKey[143]: ==>  Preparing: select id, `name` from person where id = ? 
    2020-05-04 21:26:18,497 DEBUG [main] 4664 com.mk.mybatis.multidatasource.two.base.dao.IPersonDao.selectByPrimaryKey[143]: ==> Parameters: 1(Integer)
    2020-05-04 21:26:18,506 DEBUG [main] 4673 com.mk.mybatis.multidatasource.two.base.dao.IPersonDao.selectByPrimaryKey[143]: <==      Total: 0
    null

ManDao

//@Mapper
    public interface ManDao extends IManDao {
    }

2020-05-04 21:31:04,470 DEBUG [main] 4413 com.mk.mybatis.multidatasource.one.base.dao.IManDao.selectByPrimaryKey[143]: ==>  Preparing: select id, `name` from man where id = ? 
    2020-05-04 21:31:04,499 DEBUG [main] 4442 com.mk.mybatis.multidatasource.one.base.dao.IManDao.selectByPrimaryKey[143]: ==> Parameters: 1(Integer)
    2020-05-04 21:31:04,513 DEBUG [main] 4456 com.mk.mybatis.multidatasource.one.base.dao.IManDao.selectByPrimaryKey[143]: <==      Total: 0
    null

### 二、原由 ###

由于使用了tk.mybatis的包，默认自动全包扫描@Mapper注解。tk.mybatis扫描生成的Mapper比其他自定义配置的bean生成对应的Mapper对象快，而自定义的mybatis@MapperScan后扫描，Dao Bean已经生成了，无法再指定数据源进行注入了。

### 三、解决方案 ###

（1）去掉tk.mybatis

<dependency>
                <groupId>tk.mybatis</groupId>
                <artifactId>mapper-spring-boot-starter</artifactId>
                <version>2.1.5</version>
                <exclusions>
                    <exclusion>
                        <groupId>javax.persistence</groupId>
                        <artifactId>persistence-api</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>

（2）不加@Mapper注解

//@Mapper
    public interface PersonDao extends IPersonDao {
    }

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L21vYWt1bg_size_16_color_FFFFFF_t_70]: /images/20230528/20c24d5aec4e4f9da42b6d90086ef54c.png
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