Java Utililty Methods Reflection Method Parameter

List<Class> results = new ArrayList<Class>();
Type[] genericParameterTypes = method.getGenericParameterTypes();
if (index >= genericParameterTypes.length || index < 0) {
    throw new IllegalArgumentException("index " + (index < 0 ? " must > 0 " : " over total arguments"));
Type genericParameterType = genericParameterTypes[index];
if (genericParameterType instanceof ParameterizedType) {
    ParameterizedType aType = (ParameterizedType) genericParameterType;
...

return unreflect(lookup, getMethod(receiver, methodName, parameterTypes));

if (method.getParameterTypes().length > parameterClasses.length) {
    Class<?>[] types = method.getParameterTypes();
    StringBuilder buf = new StringBuilder(rightCode);
    for (int i = parameterClasses.length; i < types.length; i++) {
        if (buf.length() > 0) {
            buf.append(",");
        Class<?> type = types[i];
...

Annotation[][] parametersAnnotations = method.getParameterAnnotations();
Annotation[] parameterAnnotations = parametersAnnotations[index];
List<A> foundAnnotations = new ArrayList<A>();
for (Annotation annotation : parameterAnnotations) {
    if (annotationClass.isInstance(annotation)) {
        foundAnnotations.add((A) annotation);
return foundAnnotations;

if ((GETPARAMETERS == null) || (m == null)) {
    return Collections.emptyMap();
Map<String, Integer> paramNames = new HashMap<String, Integer>();
try {
    Object[] params = (Object[]) GETPARAMETERS.invoke(m);
    if (params.length == 0) {
        return Collections.emptyMap();
...

final List<Class<?>> params = new ArrayList<Class<?>>();
for (Type type : method.getGenericParameterTypes()) {
    params.add(resolveClass(type, generics));
return params;

for (Method method : clazz.getMethods()) {
    if (method.getName().equals(methodName)) {
        return method.getParameterTypes();
throw new NoSuchMethodException(
        "No such method is paresent in " + clazz.getName() + " of name " + methodName);

return method.getParameterTypes();

try {
    return clazz.getMethod(methodName, parameterTypes);
} catch (NoSuchMethodException ex) {
    return null;

final Method m = getMethod(clazz, methodName, parameterTypes);
if (m != null)
    return m;
final Class<?> superclazz = clazz.getSuperclass();
if (superclazz == null)
    return null;
return getMethodRecursive(superclazz, methodName, parameterTypes);