ReflectionUtils.findMethod does not find methods for Object.class [SPR-5434]

[spring-projects-issues]

Daan Kets opened SPR-5434 and commented

ReflectionUtils.findMethod(Class<?> clazz, String methodName) javadoc states:

Attempt to find a Method on the supplied class with the supplied name and no parameters. Searches all superclasses up to Object.

Currently, the implementation does not find any results for methods declared on the Object class. As from the moment when the Object class is reached while searching, the search ends, and no result is returned. So, it's impossible for example to find the public getClass() method using findMethod(<anyObject>,"getClass"). This is pretty inconsistent with the behaviour of for example the 'getAllDeclaredMethods' method, which does return the getClass method as a result.

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Affects: 2.5.6

[spring-projects-issues]

Daan Kets commented

// Fix proposal:

public static Method findMethod(Class clazz, String name, Class[] paramTypes) {
Assert.notNull(clazz, "Class must not be null");
Assert.notNull(name, "Method name must not be null");
Class searchType = clazz;
while (searchType != null) { // CHANGED CONDITION HERE
Method[] methods = (searchType.isInterface() ? searchType.getMethods() : searchType.getDeclaredMethods());
for (int i = 0; i < methods.length; i++) {
Method method = methods[i];
if (name.equals(method.getName()) &&
(paramTypes == null || Arrays.equals(paramTypes, method.getParameterTypes()))) {
return method;
}
}
if (!Object.class.equals(searchType){ // ADDED CHECK HERE
return null;
}
searchType = searchType.getSuperclass();
}
return null;
}

[spring-projects-issues]

Juergen Hoeller commented

Good point: There's no actual reason to exclude methods on Object.class - even if those are not typically the target of such a findMethod call.

Juergen