检测是否在Java中的接口中声明了方法

Question

Help me make this method more solid:

 /**
  * Check if the method is declared in the interface.
  * Assumes the method was obtained from a concrete class that 
  * implements the interface, and return true if the method overrides
  * a method from the interface.
  */
 public static boolean isDeclaredInInterface(Method method, Class<?> interfaceClass) {
     for (Method methodInInterface : interfaceClass.getMethods())
     {
         if (methodInInterface.getName().equals(method.getName()))
             return true;
     }
     return false;
 }

Answer 1

How about this:

try {
    interfaceClass.getMethod(method.getName(), method.getParameterTypes());
    return true;
} catch (NoSuchMethodException e) {
    return false;
}

Answer 2

If you want to avoid catching NoSuchMethodException from Yashai's answer :

for (Method ifaceMethod : iface.getMethods()) {
    if (ifaceMethod.getName().equals(candidate.getName()) &&
            Arrays.equals(ifaceMethod.getParameterTypes(), candidate.getParameterTypes())) {
        return true;
    }
}
return false;

Answer 3

This is a good start:

Replace:

for (Method methodInInterface : interfaceClass.getMethods())
 {
     if (methodInInterface.getName().equals(method.getName()))
         return true;
 }

with:

for (Method methodInInterface : interfaceClass.getMethods()) {
     if (methodInInterface.getName().equals(method.getName())) {
         return true;
     }
 }

:)

Answer 4

为了使您的方法更健壮，您可能还想检查Class#isInterface()是否为给定类返回true ，否则抛出IllegalArgumentException 。

Answer 5

请参阅Method＃getDeclaringClass（） ，然后将Class对象与预期的接口进行比较。