blocks|key|383765|text|您已经找到了答案:+JDK中没有提供方法注释继承。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|383766|但是，在超类链中搜索带注释的方法也很容易实现：|383767|/**
+*+Climbs+the+super-class+chain+to+find+the+first+method+with+the+given+signature+which+is
+*+annotated+with+the+given+annotation.
+*
+*+@return+A+method+of+the+requested+signature,+applicable+to+all+instances+of+the+given
+*+++++++++class,+and+annotated+with+the+required+annotation
+*+@throws+NoSuchMethodException+If+no+method+was+found+that+matches+this+description
+*/
public+Method+getAnnotatedMethod(Class<?+extends+Annotation>+annotation,
+++++++++++++++++++++++++++++++++Class+c,+String+methodName,+Class...+parameterTypes)
++++++++throws+NoSuchMethodException+{

++++Method+method+=+c.getMethod(methodName,+parameterTypes);
++++if+(method.isAnnotationPresent(annotation))+{
++++++++return+method;
++++}

++++return+getAnnotatedMethod(annotation,+c.getSuperclass(),+methodName,+parameterTypes);
}|code-block|syntax|javascript|383768|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You found your answer already: there is no provision for method-annotation inheritance in the JDK. 

But climbing the super-class chain in search of annotated methods is also easy to implement:

<pre><code>/**
 * Climbs the super-class chain to find the first method with the given signature which is
 * annotated with the given annotation.
 *
 * @return A method of the requested signature, applicable to all instances of the given
 * class, and annotated with the required annotation
 * @throws NoSuchMethodException If no method was found that matches this description
 */
public Method getAnnotatedMethod(Class&lt;? extends Annotation&gt; annotation,
 Class c, String methodName, Class... parameterTypes)
 throws NoSuchMethodException {

 Method method = c.getMethod(methodName, parameterTypes);
 if (method.isAnnotationPresent(annotation)) {
 return method;
 }

 return getAnnotatedMethod(annotation, c.getSuperclass(), methodName, parameterTypes);
}
</code></pre>

blocks|key|599725|text|虽然问题的答案是Java的Method.getAnnotation()不考虑被覆盖的方法，但有时找到这些注释是有用的。以下是我目前正在使用的Saintali答案的更完整版本：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|599726|public+static+<A+extends+Annotation>+A+getInheritedAnnotation(
++++Class<A>+annotationClass,+AnnotatedElement+element)
{
++++A+annotation+=+element.getAnnotation(annotationClass);
++++if+(annotation+==+null+&&+element+instanceof+Method)
++++++++annotation+=+getOverriddenAnnotation(annotationClass,+(Method)+element);
++++return+annotation;
}

private+static+<A+extends+Annotation>+A+getOverriddenAnnotation(
++++Class<A>+annotationClass,+Method+method)
{
++++final+Class<?>+methodClass+=+method.getDeclaringClass();
++++final+String+name+=+method.getName();
++++final+Class<?>[]+params+=+method.getParameterTypes();

++++//+prioritize+all+superclasses+over+all+interfaces
++++final+Class<?>+superclass+=+methodClass.getSuperclass();
++++if+(superclass+!=+null)
++++{
++++++++final+A+annotation+=
++++++++++++getOverriddenAnnotationFrom(annotationClass,+superclass,+name,+params);
++++++++if+(annotation+!=+null)
++++++++++++return+annotation;
++++}

++++//+depth-first+search+over+interface+hierarchy
++++for+(final+Class<?>+intf+:+methodClass.getInterfaces())
++++{
++++++++final+A+annotation+=
++++++++++++getOverriddenAnnotationFrom(annotationClass,+intf,+name,+params);
++++++++if+(annotation+!=+null)
++++++++++++return+annotation;
++++}

++++return+null;
}

private+static+<A+extends+Annotation>+A+getOverriddenAnnotationFrom(
++++Class<A>+annotationClass,+Class<?>+searchClass,+String+name,+Class<?>[]+params)
{
++++try
++++{
++++++++final+Method+method+=+searchClass.getMethod(name,+params);
++++++++final+A+annotation+=+method.getAnnotation(annotationClass);
++++++++if+(annotation+!=+null)
++++++++++++return+annotation;
++++++++return+getOverriddenAnnotation(annotationClass,+method);
++++}
++++catch+(final+NoSuchMethodException+e)
++++{
++++++++return+null;
++++}
}|code-block|syntax|javascript|599727|entityMap^0|D|M|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

While the answer to the question as asked is that Java's <code>Method.getAnnotation()</code> does not consider overridden methods, sometimes it is useful to find these annotations. Here is a more complete version of Saintali's answer that I'm currently using:

<pre><code>public static &lt;A extends Annotation&gt; A getInheritedAnnotation(
 Class&lt;A&gt; annotationClass, AnnotatedElement element)
{
 A annotation = element.getAnnotation(annotationClass);
 if (annotation == null &amp;&amp; element instanceof Method)
 annotation = getOverriddenAnnotation(annotationClass, (Method) element);
 return annotation;
}

private static &lt;A extends Annotation&gt; A getOverriddenAnnotation(
 Class&lt;A&gt; annotationClass, Method method)
{
 final Class&lt;?&gt; methodClass = method.getDeclaringClass();
 final String name = method.getName();
 final Class&lt;?&gt;[] params = method.getParameterTypes();

 // prioritize all superclasses over all interfaces
 final Class&lt;?&gt; superclass = methodClass.getSuperclass();
 if (superclass != null)
 {
 final A annotation =
 getOverriddenAnnotationFrom(annotationClass, superclass, name, params);
 if (annotation != null)
 return annotation;
 }

 // depth-first search over interface hierarchy
 for (final Class&lt;?&gt; intf : methodClass.getInterfaces())
 {
 final A annotation =
 getOverriddenAnnotationFrom(annotationClass, intf, name, params);
 if (annotation != null)
 return annotation;
 }

 return null;
}

private static &lt;A extends Annotation&gt; A getOverriddenAnnotationFrom(
 Class&lt;A&gt; annotationClass, Class&lt;?&gt; searchClass, String name, Class&lt;?&gt;[] params)
{
 try
 {
 final Method method = searchClass.getMethod(name, params);
 final A annotation = method.getAnnotation(annotationClass);
 if (annotation != null)
 return annotation;
 return getOverriddenAnnotation(annotationClass, method);
 }
 catch (final NoSuchMethodException e)
 {
 return null;
 }
}
</code></pre>

blocks|key|599779|text|使用Spring+Core，您可以通过|type|unstyled|depth|inlineStyleRanges|entityRanges|data|599780|AnnotationUtils.java|offset|length|599781|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.spring.io/spring-framework/docs/3.2.x/javadoc-api/org/springframework/core/annotation/AnnotationUtils.html#findAnnotation(java.lang.reflect.Method,%2520java.lang.Class)^0|0|0|K|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@$D|P|E|Q|1|R]]|A|$]]|$1|F|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]]]

Using Spring Core you can resolve with

<a href="http://docs.spring.io/spring-framework/docs/3.2.x/javadoc-api/org/springframework/core/annotation/AnnotationUtils.html#findAnnotation(java.lang.reflect.Method,%20java.lang.Class)" rel="noreferrer">AnnotationUtils.java</a>

I have a parent class <code>Parent</code> and a child class <code>Child</code>, defined thus:
<pre><code>class Parent {
 @MyAnnotation(&quot;hello&quot;)
 void foo() {
 // implementation irrelevant
 }
}
class Child extends Parent {
 @Override
 foo() {
 // implementation irrelevant
 }
}
</code></pre>
If I obtain a <code>Method</code> reference to <code>Child::foo</code>, will <code>childFoo.getAnnotation(MyAnnotation.class)</code> give me <code>@MyAnnotation</code>? Or will it be <code>null</code>?
I'm interested more generally in how or whether annotation works with Java inheritance.

How do Java method annotations work in conjunction with method overriding?

Java

我有一个父类Parent和一个子类Child，定义如下：class Parent {    @MyAnnotation("hello")    void foo() {        // implementation irrelevant    }}class Child extends Parent {    @O...

问Java方法注释如何与方法覆盖结合使用？
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