protected List findEligibleAdvisors(Class beanClass, String beanName) {
List candidateAdvisors = findCandidateAdvisors();
List eligibleAdvisors = findAdvisorsThatCanApply(candidateAdvisors, beanClass, beanName);
extendAdvisors(eligibleAdvisors);
if (!eligibleAdvisors.isEmpty()) {
eligibleAdvisors = sortAdvisors(eligibleAdvisors);
}
return eligibleAdvisors;
}
findAdvisorsThatCanApply方法寻找bean所匹配的增强器。
protected List findAdvisorsThatCanApply(List candidateAdvisors, Class beanClass, String beanName) {
ProxyCreationContext.setCurrentProxiedBeanName(beanName);
try {
return AopUtils.findAdvisorsThatCanApply(candidateAdvisors, beanClass);
}
finally {
ProxyCreationContext.setCurrentProxiedBeanName(null);
}
}
AopUtilsfindAdvisors.ThatCanApply方法具体实现
public static List findAdvisorsThatCanApply(List candidateAdvisors, Class clazz) {
if (candidateAdvisors.isEmpty()) {
return candidateAdvisors;
}
List eligibleAdvisors = new LinkedList();
for (Advisor candidate : candidateAdvisors) {
//IntroductionAdvisor单独处理
if (candidate instanceof IntroductionAdvisor && canApply(candidate, clazz)) {
eligibleAdvisors.add(candidate);
}
}
boolean hasIntroductions = !eligibleAdvisors.isEmpty();
for (Advisor candidate : candidateAdvisors) {
if (candidate instanceof IntroductionAdvisor) {
// already processed
continue;
}
if (canApply(candidate, clazz, hasIntroductions)) {
eligibleAdvisors.add(candidate);
}
}
return eligibleAdvisors;
}
主要看canApply方法，IntroductionAdvisor和PointcutAdvisor也是分开处理，咱们主要看PointcutAdvisor
public static boolean canApply(Advisor advisor, Class targetClass, boolean hasIntroductions) {
if (advisor instanceof IntroductionAdvisor) {
return ((IntroductionAdvisor) advisor).getClassFilter().matches(targetClass);
}
else if (advisor instanceof PointcutAdvisor) {
PointcutAdvisor pca = (PointcutAdvisor) advisor;
return canApply(pca.getPointcut(), targetClass, hasIntroductions);
}
else {
// It doesn't have a pointcut so we assume it applies.
return true;
}
}
canApply方法
public static boolean canApply(Pointcut pc, ClasstargetClass, boolean hasIntroductions) {
Assert.notNull(pc, "Pointcut must not be null");
if (!pc.getClassFilter().matches(targetClass)) {
return false;
}MethodMatcher methodMatcher = pc.getMethodMatcher();
if (methodMatcher == MethodMatcher.TRUE) {// No need to iterate the methods if we're matching any method anyway...return true;
}
IntroductionAwareMethodMatcher introductionAwareMethodMatcher = null;
if (methodMatcher instanceof IntroductionAwareMethodMatcher) {introductionAwareMethodMatcher = (IntroductionAwareMethodMatcher) methodMatcher;}
Set> classes = new LinkedHashSet>(ClassUtils.getAllInterfacesForClassAsSet(targetClass));
classes.add(targetClass);
for (Class clazz : classes) {
Method[] methods = ReflectionUtils.getAllDeclaredMethods(clazz);
for (Method method : methods) {
if ((introductionAwareMethodMatcher != null &&
introductionAwareMethodMatcher.matches(method, targetClass, hasIntroductions)) ||
methodMatcher.matches(method, targetClass)) {
return true;
}
}
}
return false;
}
这里主要遍历目标类所有方法，看是否有匹配。
