@Mapper
public interface PayMapper {

	@Select("select * from city")
	public List<Map<String,Object>> list();
}

public class MyFactoryBean implements FactoryBean, InvocationHandler {
	private Class aClass;

	public MyFactoryBean(Class aClass) {
		this.aClass = aClass;
	}

	@Override
	public Object getObject() throws Exception {
		Class[] interfaces = new Class[]{aClass};
		Object proxyInstance = Proxy.newProxyInstance(this.getClass().getClassLoader(), interfaces, this);
		return proxyInstance;
	}

	@Override
	public Class<?> getObjectType() {
		return null;
	}

	@Override
	public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
		System.out.println("代理對(duì)象,獲取sql語(yǔ)句");
		Method method1 = proxy.getClass().getInterfaces()[0].getMethod(method.getName(), null);
		Select declaredAnnotation = method1.getDeclaredAnnotation(Select.class);
		System.out.println(declaredAnnotation.value()[0]);
		return null;
	}
}

public class MyImportDefinitionRegistrar implements ImportBeanDefinitionRegistrar {
	@Override
	public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
		BeanDefinitionBuilder beanDefinitionBuilder = BeanDefinitionBuilder.genericBeanDefinition(PayMapper.class);
		AbstractBeanDefinition beanDefinition = beanDefinitionBuilder.getBeanDefinition();
		//TODO: 注入類(lèi)型
		beanDefinition.setBeanClass(MyFactoryBean.class);
		//TODO: 注入構(gòu)造方法
		beanDefinition.getConstructorArgumentValues().addGenericArgumentValue("com.luoyan.dao.mapper.PayMapper");
		//TODO: 放入到beanDefinitionMap中
		registry.registerBeanDefinition("payServiceTest",beanDefinition);
	}
}

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
@Documented
@Import(MyImportDefinitionRegistrar.class)
public @interface LuoyanImportBeanDefinitionRegistrar {
}

@Configuration
@ComponentScan("com.luoyan")
@MapperScan("com.luoyan.dao.mapper")
@LuoyanImportBeanDefinitionRegistrar
public class AppConfig {
	
}

public static void main(String[] args) {
	AnnotationConfigApplicationContext applicationContext = new AnnotationConfigApplicationContext();
	applicationContext.register(AppConfig.class);
	applicationContext.addBeanFactoryPostProcessor(new MyBeanFactoryPostProcessor());
	applicationContext.refresh();

	PayMapper payServiceTest = (PayMapper) applicationContext.getBean("payServiceTest");
	payServiceTest.list();
}

private void processImports(ConfigurationClass configClass, SourceClass currentSourceClass,
		Collection<SourceClass> importCandidates, Predicate<String> exclusionFilter,
		boolean checkForCircularImports) {

	if (importCandidates.isEmpty()) {
		return;
	}

	if (checkForCircularImports && isChainedImportOnStack(configClass)) {
		this.problemReporter.error(new CircularImportProblem(configClass, this.importStack));
	}
	else {
		this.importStack.push(configClass);
		try {
			/**
			 *
			 * 因?yàn)锧Import(xxx.class,xxxx.class)這里可以放多個(gè)
			 * importCandidates：表示被放在@Import注解中的class類(lèi)的報(bào)名+類(lèi)名。比如：com.shadow.imports.MyImportSelector.
			 * candidate：就表示com.shadow.imports.MyImportSelector
			 */
			for (SourceClass candidate : importCandidates) {
				/**
				 * ImportSelector,判斷這個(gè)MyImportSelector.class是否實(shí)現(xiàn)了ImportSelector類(lèi)
				 */
				if (candidate.isAssignable(ImportSelector.class)) {
					// Candidate class is an ImportSelector -> delegate to it to determine imports
					//得到Import的類(lèi)loadClass
					Class<?> candidateClass = candidate.loadClass();
					//反射實(shí)現(xiàn)一個(gè)對(duì)象
					//這個(gè)instantiateClass()方法底層比較復(fù)雜
					/******************************instantiateClass()這個(gè)方法很重要*************************************/
					//new出來(lái)當(dāng)前實(shí)現(xiàn)了ImportSelector接口的類(lèi)對(duì)象
					ImportSelector selector = ParserStrategyUtils.instantiateClass(candidateClass, ImportSelector.class,
							this.environment, this.resourceLoader, this.registry);
					Predicate<String> selectorFilter = selector.getExclusionFilter();
					if (selectorFilter != null) {
						exclusionFilter = exclusionFilter.or(selectorFilter);
					}
					if (selector instanceof DeferredImportSelector) {
						this.deferredImportSelectorHandler.handle(configClass, (DeferredImportSelector) selector);
					}
					else {
						/**
						 * 這里重點(diǎn)
						 * 普通類(lèi)就是加了@component類(lèi)
						 */
						//得到所有字符串.//循環(huán)引用這類(lèi)用的是遞歸,就是說(shuō)你配置類(lèi)上有了@Impont,但是你實(shí)現(xiàn)了ImportSelector類(lèi)的類(lèi)上還是有@Impont
						//TODO: selector表示你實(shí)現(xiàn)ImportSelector接口的類(lèi)的對(duì)象.
						String[] importClassNames = selector.selectImports(currentSourceClass.getMetadata());
						//把名字傳入得到importSourceClasses,把這個(gè)類(lèi)添加到annotation這個(gè)變量中去了asSourceClasses()這個(gè)方法.
						//importClassNames=com.shadow.service.TestService3
						Collection<SourceClass> importSourceClasses = asSourceClasses(importClassNames, exclusionFilter);
						//然后又進(jìn)行循環(huán)判斷了.繼續(xù)調(diào)用processImports()方法,剛剛進(jìn)來(lái)的時(shí)候也是這個(gè)方法.
						//遞歸,這里第二次調(diào)用processImports.
						//如果是一個(gè)普通類(lèi),會(huì)進(jìn)else
						processImports(configClass, currentSourceClass, importSourceClasses, exclusionFilter, false);
					}
				}
				/**
				 * ImportBeanDefinitionRegistrar實(shí)現(xiàn)了這個(gè)接口的類(lèi)放到了addImportBeanDefinitionRegistrar()方法
				 * importBeanDefinitionRegistrarsMap當(dāng)中去了。
				 * 而
				 * 實(shí)現(xiàn)ImportSelector接口的類(lèi)卻放到了configurationClassesMap當(dāng)中去了。
				 * 所以在解析這些類(lèi)的時(shí)候使用了不同的方法存放this.reader.loadBeanDefinitions(configClasses);
				 *
				 */
				else if (candidate.isAssignable(ImportBeanDefinitionRegistrar.class)) {
					// Candidate class is an ImportBeanDefinitionRegistrar ->
					// delegate to it to register additional com.luoyan.bean definitions
					Class<?> candidateClass = candidate.loadClass();
					ImportBeanDefinitionRegistrar registrar =
							ParserStrategyUtils.instantiateClass(candidateClass, ImportBeanDefinitionRegistrar.class,
									this.environment, this.resourceLoader, this.registry);
					configClass.addImportBeanDefinitionRegistrar(registrar, currentSourceClass.getMetadata());
				}
				/**
				 * 普通的
				 */
				else {
					// Candidate class not an ImportSelector or ImportBeanDefinitionRegistrar ->
					// process it as an @Configuration class
					/**
					 * 否則,加入到importStack后調(diào)用processConfigurationClass進(jìn)行處理
					 * processConfiguration里面主要就是把類(lèi)放到configrationClasses
					 * 可以看到普通類(lèi)再掃描出來(lái)的時(shí)候就被注冊(cè)了
					 * 如果importSelector,回顯放到configurationClasses后面進(jìn)行注冊(cè)
					 * 注意這里的processConfigurationClass前面已經(jīng)解釋過(guò)這個(gè)方法了
					 */
					this.importStack.registerImport(
							currentSourceClass.getMetadata(), candidate.getMetadata().getClassName());
					//processConfigurationClass()這個(gè)方法,是繼續(xù)判斷當(dāng)前普通類(lèi)是否加了@Configuration注解
					//candidate.asConfigClass(configClass)這個(gè)方法,是把通過(guò)@Import注解得到的類(lèi),執(zhí)行方法后,得到返回回來(lái)的類(lèi)字符串,反射出來(lái)的類(lèi).放入到this.importedBy.add(importedBy);集合中
					//真正導(dǎo)入到spring的BeanDefinitionMap中的時(shí)候使用到
					processConfigurationClass(candidate.asConfigClass(configClass), exclusionFilter);
				}
			}
		}
		catch (BeanDefinitionStoreException ex) {
			throw ex;
		}
		catch (Throwable ex) {
			throw new BeanDefinitionStoreException(
					"Failed to process import candidates for configuration class [" +
					configClass.getMetadata().getClassName() + "]", ex);
		}
		finally {
			this.importStack.pop();
		}
	}
}

private void loadBeanDefinitionsFromRegistrars(Map<ImportBeanDefinitionRegistrar, AnnotationMetadata> registrars) {
	registrars.forEach((registrar, metadata) ->
			/**
			 * 這個(gè)registrar.registerBeanDefinitions就是自己實(shí)現(xiàn)了ImportBeanDefinitionRegistrar接口
			 * 的類(lèi)中邏輯,注冊(cè)到beanMap中的方法
			 */
			registrar.registerBeanDefinitions(metadata, this.registry, this.importBeanNameGenerator));
}