踩坑集锦之Mybaits Invalid bound statement异常

org.apache.ibatis.binding.bindingexception: 
invalid bound statement (not found): 
com.dhy.testMapper.query

    @Bean
    public SqlSessionFactory sqlSessionFactoryOfDataSourceA(@Qualifier("datasourceA") DataSource dataSourceA) throws Exception {
        SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean();
        sessionFactoryBean.setDataSource(dataSourceA);
        sessionFactoryBean.setConfigLocation(configLocation);
        sessionFactoryBean.setTypeAliasesPackage("com.dhy.mapper");
        Resource[] resources = new PathMatchingResourcePatternResolver().getResources("classpath:dhy/mapper/*.xml");
        sessionFactoryBean.setMapperLocations(resources);
        return sessionFactoryBean.getObject();
    }

    @Bean
    public MapperScannerConfigurer mapperScannerConfigurerOfDataSourceA() {
        MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
        mapperScannerConfigurer.setSqlSessionFactoryBeanName("sqlSessionFactoryOfDataSourceA");
        mapperScannerConfigurer.setBasePackage("com.dhy.mapper");
        return mapperScannerConfigurer;
    }

    @Bean
    public SqlSessionFactory sqlSessionFactoryOfDataSourceB(@Qualifier("datasourceB") DataSource dataSourceB) throws Exception {
        SqlSessionFactoryBean sessionFactoryBean = new SqlSessionFactoryBean();
        sessionFactoryBean.setDataSource(dataSourceB);
        sessionFactoryBean.setConfigLocation(configLocation);
        sessionFactoryBean.setTypeAliasesPackage("com.dhy.mapper.b");
        Resource[] resources = new PathMatchingResourcePatternResolver().getResources("classpath:dhy/mapper/*.xml");
        sessionFactoryBean.setMapperLocations(resources);
        return sessionFactoryBean.getObject();
    }

    @Bean
    public MapperScannerConfigurer mapperScannerConfigurerOfDataSourceB() {
        MapperScannerConfigurer mapperScannerConfigurer = new MapperScannerConfigurer();
        mapperScannerConfigurer.setSqlSessionFactoryBeanName("sqlSessionFactoryOfDataSourceB");
        mapperScannerConfigurer.setBasePackage("com.dhy.mapper.b");
        return mapperScannerConfigurer;
    }

/**
 Auto-Configuration for Mybatis. 
 Contributes a SqlSessionFactory and a SqlSessionTemplate. 
 If org.mybatis.spring.annotation.MapperScan is used, 
 or a configuration file is specified as a property, 
 those will be considered, 
 otherwise this auto-configuration will attempt to register mappers 
 based on the interface definitions in or under the root auto-configuration package.
 */
@org.springframework.context.annotation.Configuration
@ConditionalOnClass({ SqlSessionFactory.class, SqlSessionFactoryBean.class })
@ConditionalOnBean(DataSource.class)
@EnableConfigurationProperties(MybatisProperties.class)
@AutoConfigureAfter(DataSourceAutoConfiguration.class)
public class MybatisAutoConfiguration {
  ... 
  //如果我们不提供SqlSessionFactory,默认会自动注入一个
  @Bean
  @ConditionalOnMissingBean
  public SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception {
    ...
  }
  //如果我们不提供SqlSessionTemplate ,默认会自动注入一个
  @Bean
  @ConditionalOnMissingBean
  public SqlSessionTemplate sqlSessionTemplate(SqlSessionFactory sqlSessionFactory) {
       ...
  }

  /**
   MapperScan ultimately ends up creating instances of MapperFactoryBean. 
   If MapperScan is used then this auto-configuration is not needed. 
   If it is _not_ used, however, then this will bring in a bean registrar and automatically register components based on the same component-scanning path as Spring Boot itself.
   */
  @org.springframework.context.annotation.Configuration
  @Import({ AutoConfiguredMapperScannerRegistrar.class })
  @ConditionalOnMissingBean(MapperFactoryBean.class)
  public static class MapperScannerRegistrarNotFoundConfiguration {

    @PostConstruct
    public void afterPropertiesSet() {
      logger.debug("No {} found.", MapperFactoryBean.class.getName());
    }
  }

}

  /**
   This will just scan the same base package as Spring Boot does. 
   If you want more power, you can explicitly use org.mybatis.spring.annotation.MapperScan but this will get typed mappers working correctly, out-of-the-box, similar to using Spring Data JPA repositories.
   */
  public static class AutoConfiguredMapperScannerRegistrar
      implements BeanFactoryAware, ImportBeanDefinitionRegistrar, ResourceLoaderAware {
    private BeanFactory beanFactory;
    private ResourceLoader resourceLoader;

    @Override
    public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
      logger.debug("Searching for mappers annotated with @Mapper");
      //mybaits提供的mapper扫描器 
      ClassPathMapperScanner scanner = new ClassPathMapperScanner(registry);
      try {
        if (this.resourceLoader != null) {
          scanner.setResourceLoader(this.resourceLoader);
        }
        //获取SpringBoot当前项目的包扫描路径
        List<String> packages = AutoConfigurationPackages.get(this.beanFactory);
        ...
        //设置根据注解进行过滤
        scanner.setAnnotationClass(Mapper.class);
        //注册包扫描过程用用户过滤预期结果集合的Filter
        //我们上面设置了注解后,这里就会被封装为AnnotationTypeFilter注册进扫描器中
        scanner.registerFilters();
        //包扫描
        scanner.doScan(StringUtils.toStringArray(packages));
      }...
    }
    ...
  }

  /**
   * Calls the parent search that will search and register all the candidates. Then the registered objects are post
   * processed to set them as MapperFactoryBeans
   */
  @Override
  public Set<BeanDefinitionHolder> doScan(String... basePackages) {
    //调用ClassPathBeanDefinitionScanner的doScan方法,完成包扫描和Filter过滤
    Set<BeanDefinitionHolder> beanDefinitions = super.doScan(basePackages);

    if (beanDefinitions.isEmpty()) {
      LOGGER.warn(() -> "No MyBatis mapper was found in '" + Arrays.toString(basePackages)
          + "' package. Please check your configuration.");
    } else {
      //mybaits负责进行bean定义处理
      processBeanDefinitions(beanDefinitions);
    }

    return beanDefinitions;
  }

  private void processBeanDefinitions(Set<BeanDefinitionHolder> beanDefinitions) {
    AbstractBeanDefinition definition;
    BeanDefinitionRegistry registry = getRegistry();
    for (BeanDefinitionHolder holder : beanDefinitions) {
      definition = (AbstractBeanDefinition) holder.getBeanDefinition();
      ...
      // the mapper interface is the original class of the bean
      // but, the actual class of the bean is MapperFactoryBean
      //为MapperFactoryBean添加构造器参数
      definition.getConstructorArgumentValues().addGenericArgumentValue(beanClassName); // issue #59
      //添加属性注入关系映射
      definition.getPropertyValues().add("mapperInterface", Resources.classForName(beanClassName));
      //设置当前bean实际类型为mapperFactoryBeanClass
      definition.setBeanClass(this.mapperFactoryBeanClass);
      //添加属性注入关系映射
      definition.getPropertyValues().add("addToConfig", this.addToConfig);
      ...
      //我们是否设置了ClassPathMapperScanner的sqlSessionFactoryBeanName属性
      //设置了该属性表明,由当前扫描器扫描得到的mapper接口，最终都会交给这个sqlSessionFactory管理
      boolean explicitFactoryUsed = false;
      if (StringUtils.hasText(this.sqlSessionFactoryBeanName)) {
        //如果设置了,那么添加属性映射
        definition.getPropertyValues().add("sqlSessionFactory",
            //RuntimeBeanReference在bean的属性注入阶段会被替换为实际的sqlSessionFactoryBean实例
            new RuntimeBeanReference(this.sqlSessionFactoryBeanName));
        explicitFactoryUsed = true;
      } else if (this.sqlSessionFactory != null) {
        //或者我们直接指定了sqlSessionFactory对象实例,那么就可以将RuntimeBeanReference直接替换为实际的bean实例
        definition.getPropertyValues().add("sqlSessionFactory", this.sqlSessionFactory);
        explicitFactoryUsed = true;
      }
      
      //如果指定了sqlSessionTemplate也可以,处理同上
      if (StringUtils.hasText(this.sqlSessionTemplateBeanName)) {
        if (explicitFactoryUsed) {
          LOGGER.warn(
              () -> "Cannot use both: sqlSessionTemplate and sqlSessionFactory together. sqlSessionFactory is ignored.");
        }
        definition.getPropertyValues().add("sqlSessionTemplate",
            new RuntimeBeanReference(this.sqlSessionTemplateBeanName));
        explicitFactoryUsed = true;
      } else if (this.sqlSessionTemplate != null) {
        if (explicitFactoryUsed) {
          LOGGER.warn(
              () -> "Cannot use both: sqlSessionTemplate and sqlSessionFactory together. sqlSessionFactory is ignored.");
        }
        definition.getPropertyValues().add("sqlSessionTemplate", this.sqlSessionTemplate);
        explicitFactoryUsed = true;
      }
     
      //如果sqlSessionTemplate和sqlSessionFactory都没有指定过,那么设置支持自动注入
      if (!explicitFactoryUsed) {
        LOGGER.debug(() -> "Enabling autowire by type for MapperFactoryBean with name '" + holder.getBeanName() + "'.");
        definition.setAutowireMode(AbstractBeanDefinition.AUTOWIRE_BY_TYPE);
      }
      //设置当前bean是否需要进行懒加载
      definition.setLazyInit(lazyInitialization);
      ...
       //作用域设置
      if (ConfigurableBeanFactory.SCOPE_SINGLETON.equals(definition.getScope()) && defaultScope != null) {
        definition.setScope(defaultScope);
      }
      ...
    }
  }

	protected void populateBean(String beanName, RootBeanDefinition mbd, @Nullable BeanWrapper bw) {
		...
		//获取beanDefintion中已有的PropertyValues集合---集合中可能存在依赖注入映射关系了
		//例如: 我们通过xml配置了当前bean,或者像上面那样手动操作PropertyValues集合
		PropertyValues pvs = (mbd.hasPropertyValues() ? mbd.getPropertyValues() : null);
		//获取当前bean的自动注入模式--默认是不开启的
		int resolvedAutowireMode = mbd.getResolvedAutowireMode();
		//如果当前bean开启了自动注入模式,那么判断是按照名称注入,还是按照类型注入
		//例如: 如果开启了自动注入模式,并且按照类型自动注入,那么spring会尝试为当前bean每个属性都进行自动注入
		//如果某几个属性可以按照类型自动注入成功,那么就创建好对应的依赖注入映射关系---propertyValue
		//然后把propertyValue加入当前bean已有的PropertyValues集合
		if (resolvedAutowireMode == AUTOWIRE_BY_NAME || resolvedAutowireMode == AUTOWIRE_BY_TYPE) {
			MutablePropertyValues newPvs = new MutablePropertyValues(pvs);
			// Add property values based on autowire by name if applicable.
			if (resolvedAutowireMode == AUTOWIRE_BY_NAME) {
				autowireByName(beanName, mbd, bw, newPvs);
			}
			// Add property values based on autowire by type if applicable.
			if (resolvedAutowireMode == AUTOWIRE_BY_TYPE) {
				autowireByType(beanName, mbd, bw, newPvs);
			}
			pvs = newPvs;
		}
        //后置处理器处理注解方式指定的依赖关系映射注入逻辑省略
		...
        //最终使用BeanWrapper配合spring的类型转换模块
        //根据PropertyValues集合中保存的依赖注入映射关系,完成基于setter方法的依赖注入
		if (pvs != null) {
			applyPropertyValues(beanName, mbd, bw, pvs);
		}
	}

	/**
	 Check the given candidate's bean name, determining whether the corresponding bean definition needs to be registered or conflicts with an existing definition.
	 */
	protected boolean checkCandidate(String beanName, BeanDefinition beanDefinition) throws IllegalStateException {
		if (!this.registry.containsBeanDefinition(beanName)) {
			return true;
		}
		BeanDefinition existingDef = this.registry.getBeanDefinition(beanName);
		BeanDefinition originatingDef = existingDef.getOriginatingBeanDefinition();
		if (originatingDef != null) {
			existingDef = originatingDef;
		}
		//两个bean的定义是相同的,即相互兼容的
		if (isCompatible(beanDefinition, existingDef)) {
			return false;
		}
		//如果两个bean是同名的,但是bean定义不兼容,则会抛出异常,报告出现了一个beanName映射到两个不同bean上的错误
		throw new ConflictingBeanDefinitionException("Annotation-specified bean name '" + beanName +
				"' for bean class [" + beanDefinition.getBeanClassName() + "] conflicts with existing, " +
				"non-compatible bean definition of same name and class [" + existingDef.getBeanClassName() + "]");
	}

  @Override
  public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) {
    if (this.processPropertyPlaceHolders) {
      processPropertyPlaceHolders();
    }
    //根据我们向MapperScannerConfigurer设置的值，再设置到ClassPathMapperScanner 中
    ClassPathMapperScanner scanner = new ClassPathMapperScanner(registry);
    scanner.setAddToConfig(this.addToConfig);
    scanner.setAnnotationClass(this.annotationClass);
    scanner.setMarkerInterface(this.markerInterface);
    scanner.setSqlSessionFactory(this.sqlSessionFactory);
    scanner.setSqlSessionTemplate(this.sqlSessionTemplate);
    scanner.setSqlSessionFactoryBeanName(this.sqlSessionFactoryBeanName);
    scanner.setSqlSessionTemplateBeanName(this.sqlSessionTemplateBeanName);
    scanner.setResourceLoader(this.applicationContext);
    scanner.setBeanNameGenerator(this.nameGenerator);
    scanner.setMapperFactoryBeanClass(this.mapperFactoryBeanClass);
    if (StringUtils.hasText(lazyInitialization)) {
      scanner.setLazyInitialization(Boolean.valueOf(lazyInitialization));
    }
    if (StringUtils.hasText(defaultScope)) {
      scanner.setDefaultScope(defaultScope);
    }
    //注册Filter,然后启动包扫描,包扫描路径就是我们在@Bean方法中设置的
    scanner.registerFilters();
    scanner.scan(
        StringUtils.tokenizeToStringArray(this.basePackage, ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS));
  }

@Override
  public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
     //取出注解中所有属性
    AnnotationAttributes mapperScanAttrs = AnnotationAttributes
        .fromMap(importingClassMetadata.getAnnotationAttributes(MapperScan.class.getName()));
    //注册MapperScannerConfigurer
    if (mapperScanAttrs != null) {
      registerBeanDefinitions(importingClassMetadata, mapperScanAttrs, registry,
          generateBaseBeanName(importingClassMetadata, 0));
    }
  }

  void registerBeanDefinitions(AnnotationMetadata annoMeta, AnnotationAttributes annoAttrs,
      BeanDefinitionRegistry registry, String beanName) {
    // 要注册的bean类型为MapperScannerConfigurer
    BeanDefinitionBuilder builder = BeanDefinitionBuilder.genericBeanDefinition(MapperScannerConfigurer.class);
    
    builder.addPropertyValue("processPropertyPlaceHolders", true);
    //如果指定了包扫描的同时按照注解进行过滤那就进行设置,默认是会将指定包下所有接口都搜集起来
    Class<? extends Annotation> annotationClass = annoAttrs.getClass("annotationClass");
    if (!Annotation.class.equals(annotationClass)) {
      builder.addPropertyValue("annotationClass", annotationClass);
    }
    
    Class<?> markerInterface = annoAttrs.getClass("markerInterface");
    if (!Class.class.equals(markerInterface)) {
      builder.addPropertyValue("markerInterface", markerInterface);
    }

    Class<? extends BeanNameGenerator> generatorClass = annoAttrs.getClass("nameGenerator");
    if (!BeanNameGenerator.class.equals(generatorClass)) {
      builder.addPropertyValue("nameGenerator", BeanUtils.instantiateClass(generatorClass));
    }

    Class<? extends MapperFactoryBean> mapperFactoryBeanClass = annoAttrs.getClass("factoryBean");
    if (!MapperFactoryBean.class.equals(mapperFactoryBeanClass)) {
      builder.addPropertyValue("mapperFactoryBeanClass", mapperFactoryBeanClass);
    }

    String sqlSessionTemplateRef = annoAttrs.getString("sqlSessionTemplateRef");
    if (StringUtils.hasText(sqlSessionTemplateRef)) {
      builder.addPropertyValue("sqlSessionTemplateBeanName", annoAttrs.getString("sqlSessionTemplateRef"));
    }

    String sqlSessionFactoryRef = annoAttrs.getString("sqlSessionFactoryRef");
    if (StringUtils.hasText(sqlSessionFactoryRef)) {
      builder.addPropertyValue("sqlSessionFactoryBeanName", annoAttrs.getString("sqlSessionFactoryRef"));
    }
    //是否在注解中指定了包扫描路径
    List<String> basePackages = new ArrayList<>();
    basePackages.addAll(
Arrays.stream(annoAttrs.getStringArray("value")).filter(StringUtils::hasText).collect(Collectors.toList()));    basePackages.addAll(Arrays.stream(annoAttrs.getStringArray("basePackages")).filter(StringUtils::hasText)
        .collect(Collectors.toList()));
basePackages.addAll(Arrays.stream(annoAttrs.getClassArray("basePackageClasses")).map(ClassUtils::getPackageName)
        .collect(Collectors.toList()));
    //没有指定包扫描路径,则选取默认包扫描路径
    if (basePackages.isEmpty()) {
      basePackages.add(getDefaultBasePackage(annoMeta));
    }

    String lazyInitialization = annoAttrs.getString("lazyInitialization");
    if (StringUtils.hasText(lazyInitialization)) {
      builder.addPropertyValue("lazyInitialization", lazyInitialization);
    }

    String defaultScope = annoAttrs.getString("defaultScope");
    if (!AbstractBeanDefinition.SCOPE_DEFAULT.equals(defaultScope)) {
      builder.addPropertyValue("defaultScope", defaultScope);
    }

    builder.addPropertyValue("basePackage", StringUtils.collectionToCommaDelimitedString(basePackages));

    // for spring-native
    builder.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);

    registry.registerBeanDefinition(beanName, builder.getBeanDefinition());

  }

  private static String generateBaseBeanName(AnnotationMetadata importingClassMetadata, int index) {
    return importingClassMetadata.getClassName() + "#" + MapperScannerRegistrar.class.getSimpleName() + "#" + index;
  }

  private static String getDefaultBasePackage(AnnotationMetadata importingClassMetadata) {
    return ClassUtils.getPackageName(importingClassMetadata.getClassName());
  }