Spring源码解析之基于注解的SpringAOP源码解析(一)

准备工作



本文分析Spring的AOP模块的整体流程,分析过程需要使用一个简单的demo工程来启动Spring。

<code>https://github.com/cjinjun/spring-framework-demo/<code>

写一个简单的接口和实现类,跟IOC源码解析那几篇文章用的同一个工程,

<code>public interface IOCService {
public String helloIoc();
}

public class IOCServiceImpl implements IOCService {
public String helloIoc() {
return "Hello,IOC";
}
}/<code>

增加bean的配置类,以及启动AOP

<code>@EnableAspectJAutoProxy
@Configuration
public class AnnotationConfig {
@Bean
public IOCService iocService(){
return new IOCServiceImpl();
}
}/<code>

创建切点

<code>@Aspect
@Component
public class AspectJTest {

@Pointcut("execution(public * com.jinjun.demo.ioc.service..IOCService.helloIoc(..))")
public void testAOP(){}

@Before("testAOP()")
public void before(){
System.out.println("before AOP...");


}

@After("testAOP()")
public void after(){
System.out.println("after AOP...");
}

@Around("testAOP()")
public Object around(ProceedingJoinPoint p){
System.out.println("around before AOP...");
Object o = null;
try {
o = p.proceed();
} catch (Throwable e) {
e.printStackTrace();
}
System.out.println("around after AOP...");
return o;
}
}/<code>

启动spring

<code>public class AnnotationIOCDemo {
public static void main (String args[]){
ApplicationContext context = new AnnotationConfigApplicationContext("cn.shiyujun.config");
IOCService iocService=context.getBean(IOCService.class);
System.out.println(iocService.@EnableAspectJAutoProxy注解());
}
}/<code>

代码部分到此,然后首先看一下

@EnableAspectJAutoProxy注解

为了开启AOP功能,使用了一个@EnableAspectJAutoProxy注解,进入这个注解可以查看到这个注解的2个属性,相信大家都已经很熟悉了,就不相信的说明了。除此之外可以看到这个注解使用@Import注解引入了一个配置类

@Import注解:可以引入一个类,将这个类注入到Spring IOC容器中被当前Spring管理

<code>@Import(AspectJAutoProxyRegistrar.class)


public @interface EnableAspectJAutoProxy {
//proxyTargetClass属性,默认false,尝试采用JDK动态代理织入增强(如果当前类没有实现接口则还是会使用CGLIB);如果设为true,则强制采用CGLIB动态代理织入增强
boolean proxyTargetClass() default false;
//通过aop框架暴露该代理对象,aopContext能够访问。为了解决类内部方法之间调用时无法增强的问题
boolean exposeProxy() default false;
}/<code>

看一下这个配置类的操作

<code>
class AspectJAutoProxyRegistrar implements ImportBeanDefinitionRegistrar {
AspectJAutoProxyRegistrar() {
}

public void registerBeanDefinitions(AnnotationMetadata importingClassMetadata, BeanDefinitionRegistry registry) {
//注册一个AOP代理实现的Bean,往下看 AopConfigUtils.registerAspectJAnnotationAutoProxyCreatorIfNecessary(registry);
AnnotationAttributes enableAspectJAutoProxy = AnnotationConfigUtils.attributesFor(importingClassMetadata, EnableAspectJAutoProxy.class);
if (enableAspectJAutoProxy != null) {
if (enableAspectJAutoProxy.getBoolean("proxyTargetClass")) {
AopConfigUtils.forceAutoProxyCreatorToUseClassProxying(registry);
}

if (enableAspectJAutoProxy.getBoolean("exposeProxy")) {
AopConfigUtils.forceAutoProxyCreatorToExposeProxy(registry);
}
}

}
}/<code>

registerAspectJAnnotationAutoProxyCreatorIfNecessary方法的主要功能是注册或者升级AnnotationAwareAspectJAutoProxyCreator类,这个类在AOP中非常的重要,它的主要功能就是根据@Point注解定义的切点来自动代理与表达式匹配的类。下面看一个这个实现的逻辑

<code>private static BeanDefinition registerOrEscalateApcAsRequired(Class> cls, BeanDefinitionRegistry registry, @Nullable Object source) {
Assert.notNull(registry, "BeanDefinitionRegistry must not be null"); //如果已存在这个bean


if (registry.containsBeanDefinition("org.springframework.aop.config.internalAutoProxyCreator")) {
BeanDefinition apcDefinition = registry.getBeanDefinition("org.springframework.aop.config.internalAutoProxyCreator");
//判断优先级,如果优先级较高则替换原先的bean
if (!cls.getName().equals(apcDefinition.getBeanClassName())) {
int currentPriority = findPriorityForClass(apcDefinition.getBeanClassName());
int requiredPriority = findPriorityForClass(cls);
if (currentPriority < requiredPriority) {
apcDefinition.setBeanClassName(cls.getName());
}
}

return null;
} else {
//注册AnnotationAwareAspectJAutoProxyCreator到容器中,此类负责基于注解的AOP动态代理实现
RootBeanDefinition beanDefinition = new RootBeanDefinition(cls);
beanDefinition.setSource(source);
beanDefinition.getPropertyValues().add("order", -2147483648);
beanDefinition.setRole(2);
registry.registerBeanDefinition("org.springframework.aop.config.internalAutoProxyCreator", beanDefinition);
return beanDefinition;
}
}/<code>

注册的AnnotationAwareAspectJAutoProxyCreator这个类间接实现了BeanPostProcessor接口。还记得我们之前在对SpringIOC的源码进行解析时提到过,Spring在实例化Bean的前后会分别调用方法postProcessBeforeInstantiation和postProcessAfterInstantiation而AOP的整体逻辑就是通过这两个方法来实现的

postProcessBeforeInstantiation

首先看一下这个postProcessBeforeInstantiation方法,它是在bean实例化之前调用的,主要是针对切面类。这个方法不在AnnotationAwareAspectJAutoProxyCreator这个类中,而是在其父类AbstractAutoProxyCreator中

<code>public Object postProcessBeforeInstantiation(Class> beanClass, String beanName) throws BeansException {
Object cacheKey = getCacheKey(beanClass, beanName);

if (!StringUtils.hasLength(beanName) || !this.targetSourcedBeans.contains(beanName)) {
if (this.advisedBeans.containsKey(cacheKey)) {
return null;
}


//加载所有增强
if (isInfrastructureClass(beanClass) || shouldSkip(beanClass, beanName)) {
this.advisedBeans.put(cacheKey, Boolean.FALSE);
return null;
}
}

TargetSource targetSource = getCustomTargetSource(beanClass, beanName);
if (targetSource != null) {
if (StringUtils.hasLength(beanName)) {
this.targetSourcedBeans.add(beanName);
}
Object[] specificInterceptors = getAdvicesAndAdvisorsForBean(beanClass, beanName, targetSource);
Object proxy = createProxy(beanClass, beanName, specificInterceptors, targetSource);
this.proxyTypes.put(cacheKey, proxy.getClass());
return proxy;
}

return null;
}/<code>

加载增强

上方代码中最重要的一个方法就是shouldSkip方法了,被AspectJAwareAdvisorAutoProxyCreator所重载

<code>
protected boolean shouldSkip(Class> beanClass, String beanName) {

//查找所有标识了@Aspect注解的类,这里是重点,接着往下看
List<advisor> candidateAdvisors = findCandidateAdvisors();
for (Advisor advisor : candidateAdvisors) {
if (advisor instanceof AspectJPointcutAdvisor) {
if (((AbstractAspectJAdvice) advisor.getAdvice()).getAspectName().equals(beanName)) {
return true;
}
}
}
return super.shouldSkip(beanClass, beanName);
}


protected List<advisor> findCandidateAdvisors() {
return this.advisorRetrievalHelper.findAdvisorBeans();
}

protected List<advisor> findCandidateAdvisors() {


List<advisor> advisors = super.findCandidateAdvisors();
//buildAspectJAdvisors是重点
advisors.addAll(this.aspectJAdvisorsBuilder.buildAspectJAdvisors());
return advisors;
}/<advisor>/<advisor>/<advisor>/<advisor>/<code>

<code>
public List<advisor> buildAspectJAdvisors() {
//所有Aspect类的名称集合
List<string> aspectNames = this.aspectBeanNames;
if (aspectNames == null) {
synchronized (this) {
aspectNames = this.aspectBeanNames;
//这个双重检查是不是在学习安全的单例模式的时候见过
if (aspectNames == null) {
List<advisor> advisors = new LinkedList<advisor>();
aspectNames = new LinkedList<string>();
//获取所有Bean名称
String[] beanNames = BeanFactoryUtils.beanNamesForTypeIncludingAncestors(
this.beanFactory, Object.class, true, false);
for (String beanName : beanNames) {
//判断是否符合条件,比如说有时会排除一些类,不让这些类注入进Spring
if (!isEligibleBean(beanName)) {
continue;
}

Class> beanType = this.beanFactory.getType(beanName);
if (beanType == null) {
continue;
}
//判断Bean的Class上是否标识@Aspect注解
if (this.advisorFactory.isAspect(beanType)) {
aspectNames.add(beanName);
AspectMetadata amd = new AspectMetadata(beanType, beanName);
if (amd.getAjType().getPerClause().getKind() == PerClauseKind.SINGLETON) {
MetadataAwareAspectInstanceFactory factory =
new BeanFactoryAspectInstanceFactory(this.beanFactory, beanName);
//下一步说,重点的重点
List<advisor> classAdvisors = this.advisorFactory.getAdvisors(factory);
if (this.beanFactory.isSingleton(beanName)) {
//将解析的Bean名称及类上的增强缓存起来,每个Bean只解析一次


this.advisorsCache.put(beanName, classAdvisors);
}
else {
this.aspectFactoryCache.put(beanName, factory);
}
advisors.addAll(classAdvisors);
}
else {
if (this.beanFactory.isSingleton(beanName)) {
throw new IllegalArgumentException("Bean with name '" + beanName +
"' is a singleton, but aspect instantiation model is not singleton");
}
MetadataAwareAspectInstanceFactory factory =
new PrototypeAspectInstanceFactory(this.beanFactory, beanName);
this.aspectFactoryCache.put(beanName, factory);
advisors.addAll(this.advisorFactory.getAdvisors(factory));
}
}
}

this.aspectBeanNames = aspectNames;
return advisors;
}
}
}

if (aspectNames.isEmpty()) {
return Collections.emptyList();
}
List<advisor> advisors = new LinkedList<advisor>();
for (String aspectName : aspectNames) {
//从缓存中获取当前Bean的切面实例,如果不为空,则指明当前Bean的Class标识了@Aspect,且有切面方法
List<advisor> cachedAdvisors = this.advisorsCache.get(aspectName);
if (cachedAdvisors != null) {
advisors.addAll(cachedAdvisors);
}
else {
MetadataAwareAspectInstanceFactory factory = this.aspectFactoryCache.get(aspectName);
advisors.addAll(this.advisorFactory.getAdvisors(factory));
}
}
return advisors;
}/<advisor>/<advisor>/<advisor>/<advisor>/<string>/<advisor>/<advisor>/<string>/<advisor>/<code>

生成增强

advisorFactory.getAdvisors方法会从@Aspect标识的类上获取@Before,@Pointcut等注解的信息及其标识的方法的信息,生成增强

<code>public List<advisor> getAdvisors(MetadataAwareAspectInstanceFactory aspectInstanceFactory) {
Class> aspectClass = aspectInstanceFactory.getAspectMetadata().getAspectClass();
String aspectName = aspectInstanceFactory.getAspectMetadata().getAspectName();
//校验类的合法性相关
validate(aspectClass);

MetadataAwareAspectInstanceFactory lazySingletonAspectInstanceFactory =
new LazySingletonAspectInstanceFactoryDecorator(aspectInstanceFactory);

List<advisor> advisors = new LinkedList<advisor>();
//获取这个类所有的增强方法
for (Method method : getAdvisorMethods(aspectClass)) {
//生成增强实例
Advisor advisor = getAdvisor(method, lazySingletonAspectInstanceFactory, advisors.size(), aspectName);
if (advisor != null) {
advisors.add(advisor);
}
}

if (!advisors.isEmpty() && lazySingletonAspectInstanceFactory.getAspectMetadata().isLazilyInstantiated()) {
Advisor instantiationAdvisor = new SyntheticInstantiationAdvisor(lazySingletonAspectInstanceFactory);
advisors.add(0, instantiationAdvisor);
}

for (Field field : aspectClass.getDeclaredFields()) {
Advisor advisor = getDeclareParentsAdvisor(field);
if (advisor != null) {
advisors.add(advisor);
}
}

return advisors;
}

//获取类的的方法
private List<method> getAdvisorMethods(Class> aspectClass) {
final List<method> methods = new LinkedList<method>();
ReflectionUtils.doWithMethods(aspectClass, new ReflectionUtils.MethodCallback() {
@Override
public void doWith(Method method) throws IllegalArgumentException {
//在@Aspect标识的类内部排除@Pointcut标识之外的所有方法,得到的方法集合包括继承自父类的方法,包括继承自Object的方法
if (AnnotationUtils.getAnnotation(method, Pointcut.class) == null) {


methods.add(method);
}
}
});
//对得到的所有方法排序,
//如果方法标识了切面注解,则按@Around, @Before, @After, @AfterReturning, @AfterThrowing的顺序排序
//如果没有标识这些注解,则按方法名称的字符串排序,
//有注解的方法排在无注解的方法之前
//最后的排序应该是这样的Around.class, Before.class, After.class, AfterReturning.class, AfterThrowing.class。。。
Collections.sort(methods, METHOD_COMPARATOR);
return methods;
}/<method>/<method>/<method>/<advisor>/<advisor>/<advisor>/<code>

调用生成增强实例的方法

<code>public Advisor getAdvisor(Method candidateAdviceMethod, MetadataAwareAspectInstanceFactory aspectInstanceFactory,
int declarationOrderInAspect, String aspectName) {
//再次校验类的合法性
validate(aspectInstanceFactory.getAspectMetadata().getAspectClass());
//切点表达式的包装类里面包含这些东西:execution(public * cn.shiyujun.service.IOCService.hollo(..))
AspectJExpressionPointcut expressionPointcut = getPointcut(
candidateAdviceMethod, aspectInstanceFactory.getAspectMetadata().getAspectClass());
if (expressionPointcut == null) {
return null;
}
//根据方法、切点、AOP实例工厂、类名、序号生成切面实例,详细代码往下看
return new InstantiationModelAwarePointcutAdvisorImpl(expressionPointcut, candidateAdviceMethod,
this, aspectInstanceFactory, declarationOrderInAspect, aspectName);
}

private AspectJExpressionPointcut getPointcut(Method candidateAdviceMethod, Class> candidateAspectClass) {
//查询方法上的切面注解,根据注解生成相应类型的AspectJAnnotation,在调用AspectJAnnotation的构造函数的同时
//根据注解value或pointcut属性得到切点表达式,有argNames则设置参数名称


AspectJAnnotation> aspectJAnnotation =
AbstractAspectJAdvisorFactory.findAspectJAnnotationOnMethod(candidateAdviceMethod);
//过滤那些不含@Before, @Around, @After, @AfterReturning, @AfterThrowing注解的方法
if (aspectJAnnotation == null) {
return null;
}
//生成带表达式的切面切入点,设置其切入点表达式
AspectJExpressionPointcut ajexp =
new AspectJExpressionPointcut(candidateAspectClass, new String[0], new Class>[0]);
ajexp.setExpression(aspectJAnnotation.getPointcutExpression());
ajexp.setBeanFactory(this.beanFactory);
return ajexp;
}/<code>

InstantiationModelAwarePointcutAdvisorImpl的构造方法

<code>public InstantiationModelAwarePointcutAdvisorImpl(AspectJExpressionPointcut declaredPointcut,
Method aspectJAdviceMethod, AspectJAdvisorFactory aspectJAdvisorFactory,
MetadataAwareAspectInstanceFactory aspectInstanceFactory, int declarationOrder, String aspectName) {

this.declaredPointcut = declaredPointcut;
this.declaringClass = aspectJAdviceMethod.getDeclaringClass();
this.methodName = aspectJAdviceMethod.getName();
this.parameterTypes = aspectJAdviceMethod.getParameterTypes();
this.aspectJAdviceMethod = aspectJAdviceMethod;
this.aspectJAdvisorFactory = aspectJAdvisorFactory;
this.aspectInstanceFactory = aspectInstanceFactory;
this.declarationOrder = declarationOrder;
this.aspectName = aspectName;

if (aspectInstanceFactory.getAspectMetadata().isLazilyInstantiated()) {
Pointcut preInstantiationPointcut = Pointcuts.union(
aspectInstanceFactory.getAspectMetadata().getPerClausePointcut(), this.declaredPointcut);

this.pointcut = new PerTargetInstantiationModelPointcut(
this.declaredPointcut, preInstantiationPointcut, aspectInstanceFactory);
this.lazy = true;
}
else {
this.pointcut = this.declaredPointcut;
this.lazy = false;
//重点在这里
this.instantiatedAdvice = instantiateAdvice(this.declaredPointcut);
}
}

private Advice instantiateAdvice(AspectJExpressionPointcut pointcut) {


//再往下看
Advice advice = this.aspectJAdvisorFactory.getAdvice(this.aspectJAdviceMethod, pointcut,
this.aspectInstanceFactory, this.declarationOrder, this.aspectName);
return (advice != null ? advice : EMPTY_ADVICE);
}/<code>

生产增强

<code>public class ReflectiveAspectJAdvisorFactory extends AbstractAspectJAdvisorFactory implements Serializable {

public Advice getAdvice(Method candidateAdviceMethod, AspectJExpressionPointcut expressionPointcut,
MetadataAwareAspectInstanceFactory aspectInstanceFactory, int declarationOrder, String aspectName) {

Class> candidateAspectClass = aspectInstanceFactory.getAspectMetadata().getAspectClass();
//又是一次校验
validate(candidateAspectClass);

AspectJAnnotation> aspectJAnnotation =
AbstractAspectJAdvisorFactory.findAspectJAnnotationOnMethod(candidateAdviceMethod);
if (aspectJAnnotation == null) {
return null;
}

if (!isAspect(candidateAspectClass)) {
throw new AopConfigException("Advice must be declared inside an aspect type: " +
"Offending method '" + candidateAdviceMethod + "' in class [" +
candidateAspectClass.getName() + "]");
}

if (logger.isDebugEnabled()) {
logger.debug("Found AspectJ method: " + candidateAdviceMethod);
}

AbstractAspectJAdvice springAdvice;
//根据注解类型生成不同的通知实例
switch (aspectJAnnotation.getAnnotationType()) {
case AtBefore:
springAdvice = new AspectJMethodBeforeAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
break;
case AtAfter:
springAdvice = new AspectJAfterAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
break;
case AtAfterReturning:
springAdvice = new AspectJAfterReturningAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
AfterReturning afterReturningAnnotation = (AfterReturning) aspectJAnnotation.getAnnotation();
if (StringUtils.hasText(afterReturningAnnotation.returning())) {


springAdvice.setReturningName(afterReturningAnnotation.returning());
}
break;
case AtAfterThrowing:
springAdvice = new AspectJAfterThrowingAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
AfterThrowing afterThrowingAnnotation = (AfterThrowing) aspectJAnnotation.getAnnotation();
if (StringUtils.hasText(afterThrowingAnnotation.throwing())) {
springAdvice.setThrowingName(afterThrowingAnnotation.throwing());
}
break;
case AtAround:
springAdvice = new AspectJAroundAdvice(
candidateAdviceMethod, expressionPointcut, aspectInstanceFactory);
break;
case AtPointcut:
if (logger.isDebugEnabled()) {
logger.debug("Processing pointcut '" + candidateAdviceMethod.getName() + "'");
}
return null;
default:
throw new UnsupportedOperationException(
"Unsupported advice type on method: " + candidateAdviceMethod);
}

//设置通知方法所属的类
springAdvice.setAspectName(aspectName);
//设置通知的序号,同一个类中有多个切面注解标识的方法时,按上方说的排序规则来排序,
//其序号就是此方法在列表中的序号,第一个就是0
springAdvice.setDeclarationOrder(declarationOrder);
//获取通知方法的所有参数
String[] argNames = this.parameterNameDiscoverer.getParameterNames(candidateAdviceMethod);
//将通知方法上的参数设置到通知中
if (argNames != null) {
springAdvice.setArgumentNamesFromStringArray(argNames);
}
//计算参数绑定工作,此方法详解请接着往下看
springAdvice.calculateArgumentBindings();
return springAdvice;

}
}/<code>

校验方法参数并绑定

<code>public synchronized final void calculateArgumentBindings() {
if (this.argumentsIntrospected || this.parameterTypes.length == 0) {
return;
}

int numUnboundArgs = this.parameterTypes.length;
Class>[] parameterTypes = this.aspectJAdviceMethod.getParameterTypes();
//切面注解标识的方法第一个参数要求是JoinPoint,或StaticPart,若是@Around注解则也可以是ProceedingJoinPoint
if (maybeBindJoinPoint(parameterTypes[0]) || maybeBindProceedingJoinPoint(parameterTypes[0])) {
numUnboundArgs--;
}
else if (maybeBindJoinPointStaticPart(parameterTypes[0])) {
numUnboundArgs--;
}

if (numUnboundArgs > 0) {
//绑定属性
bindArgumentsByName(numUnboundArgs);
}

this.argumentsIntrospected = true;
}
private void bindArgumentsByName(int numArgumentsExpectingToBind) {
if (this.argumentNames == null) { //获取方法参数的名称
this.argumentNames = createParameterNameDiscoverer().getParameterNames(this.aspectJAdviceMethod);
}
if (this.argumentNames != null) {
// 往下看
bindExplicitArguments(numArgumentsExpectingToBind);
}
else {
throw new IllegalStateException("Advice method [" + this.aspectJAdviceMethod.getName() + "] " +
"requires " + numArgumentsExpectingToBind + " arguments to be bound by name, but " +
"the argument names were not specified and could not be discovered.");
}
}

private void bindExplicitArguments(int numArgumentsLeftToBind) {
//此属性用来存储方法未绑定的参数名称,及参数的序号


this.argumentBindings = new HashMap<string>();

int numExpectedArgumentNames = this.aspectJAdviceMethod.getParameterTypes().length;
if (this.argumentNames.length != numExpectedArgumentNames) {
throw new IllegalStateException("Expecting to find " + numExpectedArgumentNames +
" arguments to bind by name in advice, but actually found " +
this.argumentNames.length + " arguments.");
}

// So we match in number...,argumentIndexOffset代表第一个未绑定参数的顺序
int argumentIndexOffset = this.parameterTypes.length - numArgumentsLeftToBind;
for (int i = argumentIndexOffset; i < this.argumentNames.length; i++) {
//存储未绑定的参数名称及其顺序的映射关系
this.argumentBindings.put(this.argumentNames[i], i);
}

// Check that returning and throwing were in the argument names list if
// specified, and find the discovered argument types.
//如果是@AfterReturning注解的returningName 有值,验证,解析,同时得到定义返回值的类型
if (this.returningName != null) {
if (!this.argumentBindings.containsKey(this.returningName)) {
throw new IllegalStateException("Returning argument name '" + this.returningName +
"' was not bound in advice arguments");
}
else {
Integer index = this.argumentBindings.get(this.returningName);
this.discoveredReturningType = this.aspectJAdviceMethod.getParameterTypes()[index];
this.discoveredReturningGenericType = this.aspectJAdviceMethod.getGenericParameterTypes()[index];
}
}
//如果是@AfterThrowing注解的throwingName 有值,验证,解析,同时得到抛出异常的类型
if (this.throwingName != null) {
if (!this.argumentBindings.containsKey(this.throwingName)) {
throw new IllegalStateException("Throwing argument name '" + this.throwingName +
"' was not bound in advice arguments");
}
else {
Integer index = this.argumentBindings.get(this.throwingName);
this.discoveredThrowingType = this.aspectJAdviceMethod.getParameterTypes()[index];
}
}

// configure the pointcut expression accordingly.
configurePointcutParameters(argumentIndexOffset);
}

private void configurePointcutParameters(int argumentIndexOffset) {
int numParametersToRemove = argumentIndexOffset;
if (this.returningName != null) {
numParametersToRemove++;
}
if (this.throwingName != null) {
numParametersToRemove++;
}
String[] pointcutParameterNames = new String[this.argumentNames.length - numParametersToRemove];
Class>[] pointcutParameterTypes = new Class>[pointcutParameterNames.length];
Class>[] methodParameterTypes = this.aspectJAdviceMethod.getParameterTypes();

int index = 0;
for (int i = 0; i < this.argumentNames.length; i++) {
if (i < argumentIndexOffset) {
continue;
}
if (this.argumentNames[i].equals(this.returningName) ||
this.argumentNames[i].equals(this.throwingName)) {
continue;
}
pointcutParameterNames[index] = this.argumentNames[i];
pointcutParameterTypes[index] = methodParameterTypes[i];
index++;
}
//剩余的未绑定的参数会赋值给AspectJExpressionPointcut(表达式形式的切入点)的属性,以备后续使用
this.pointcut.setParameterNames(pointcutParameterNames);
this.pointcut.setParameterTypes(pointcutParameterTypes);
}/<string>/<code>

篇幅原因,本文到此结束,期待下集,下集主要说明postProcessAfterInitialization 及Aop 剩下的实现逻辑