Mybatis-Spring之灵异事件

public class MapperScannerConfigurer implements BeanFactoryPostProcessor, InitializingBean {

    private String basePackage;

    private boolean addToConfig = true;

    private SqlSessionFactory sqlSessionFactory;

    private SqlSessionTemplate sqlSessionTemplate;

    private Class<? extends Annotation> annotationClass;

    private Class<?> markerInterface;

        /<strong>
         * Calls the parent search that will search and register all the candidates. Then the
         * registered objects are post processed to set them as MapperFactoryBeans
         */
        @[author]Override[/author]
        protected Set<BeanDefinitionHolder> doScan(String... basePackages) {
            Set<BeanDefinitionHolder> beanDefinitions = super.doScan(basePackages);

            if (beanDefinitions.isEmpty()) {
                logger.warn("No MyBatis mapper was found in '" + MapperScannerConfigurer.this.basePackage
                        + "' package. Please check your configuration.");
            } else {
                for (BeanDefinitionHolder holder : beanDefinitions) {
                    GenericBeanDefinition definition = (GenericBeanDefinition) holder.getBeanDefinition();

                    if (logger.isDebugEnabled()) {
                        logger.debug("Creating MapperFactoryBean with name '" + holder.getBeanName() + "' and '"
                                + definition.getBeanClassName() + "' mapperInterface");
                    }

                    // the mapper interface is the original class of the bean
                    // but, the actual class of the bean is MapperFactoryBean
                    definition.getPropertyValues().add("mapperInterface", definition.getBeanClassName());
                    definition.setBeanClass(MapperFactoryBean.class);

                    definition.getPropertyValues().add("addToConfig", MapperScannerConfigurer.this.addToConfig);

                    if (MapperScannerConfigurer.this.sqlSessionFactory != null) {
                        definition.getPropertyValues().add("sqlSessionFactory",
                                MapperScannerConfigurer.this.sqlSessionFactory);
                    }

                    if (MapperScannerConfigurer.this.sqlSessionTemplate != null) {
                        definition.getPropertyValues().add("sqlSessionTemplate",
                                MapperScannerConfigurer.this.sqlSessionTemplate);
                    }
                }
            }

            return beanDefinitions;
        }

        @[author]Override[/author]
        protected boolean isCandidateComponent(AnnotatedBeanDefinition beanDefinition) {
            return (beanDefinition.getMetadata().isInterface() && beanDefinition.getMetadata().isIndependent());
        }

        @[author]Override[/author]
        protected boolean checkCandidate(String beanName, BeanDefinition beanDefinition) throws IllegalStateException {
            if (super.checkCandidate(beanName, beanDefinition)) {
                return true;
            } else {
                logger.warn("Skipping MapperFactoryBean with name '" + beanName + "' and '"
                        + beanDefinition.getBeanClassName() + "' mapperInterface"
                        + ". Bean already defined with the same name!");
                return false;
            }
        }
    }

}

public interface InitializingBean {
	
	/</strong>
	 * Invoked by a BeanFactory after it has set all bean properties supplied
	 * (and satisfied BeanFactoryAware and ApplicationContextAware).
	 * <p>This method allows the bean instance to perform initialization only
	 * possible when all bean properties have been set and to throw an
	 * exception in the event of misconfiguration.
	 * @throws Exception in the event of misconfiguration (such
	 * as failure to set an essential property) or if initialization fails.
	 */
	void afterPropertiesSet() throws Exception;

}

public interface BeanFactoryPostProcessor {

	/**
	 * Modify the application context's internal bean factory after its standard
	 * initialization. All bean definitions will have been loaded, but no beans
	 * will have been instantiated yet. This allows for overriding or adding
	 * properties even to eager-initializing beans.
	 * @param beanFactory the bean factory used by the application context
	 * @throws org.springframework.beans.BeansException in case of errors
	 */
	void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException;

}