/** Extract a class instance from given Type. */ private static Class<?> extractClass(Class<?> ownerClass, Type arg) { if (arg instanceof ParameterizedType) { return extractClass(ownerClass, ((ParameterizedType) arg).getRawType()); } else if (arg instanceof GenericArrayType) { GenericArrayType gat = (GenericArrayType) arg; Type gt = gat.getGenericComponentType(); Class<?> componentClass = extractClass(ownerClass, gt); return Array.newInstance(componentClass, 0).getClass(); } else if (arg instanceof TypeVariable) { TypeVariable<?> tv = (TypeVariable<?>) arg; arg = getTypeVariableMap(ownerClass).get(tv); if (arg == null) { arg = extractBoundForTypeVariable(tv); } else { arg = extractClass(ownerClass, arg); } } return (arg instanceof Class ? (Class<?>) arg : Object.class); }