code: public static Class<?> findGenericClass(final Class<?> mainClass, final Class<?>[] excludedClasses) {
  
          final boolean excludeMode = excludedClasses.length > 1;
  
          // Retrieve the generic super class Parameterized type
          final ParameterizedType paramType = (ParameterizedType) mainClass.getGenericSuperclass();
  
          Class<?> genericClass = null;
          Class<?> tempClass = null;
          for (int i = 0; genericClass == null && i < paramType.getActualTypeArguments().length; i++) {
              tempClass = getClassFromType(paramType.getActualTypeArguments()[i]);
              if (!excludeMode && excludedClasses[0].isAssignableFrom(tempClass)) {
                  genericClass = tempClass;
              }
              if (excludeMode) {
                  boolean excludeIt = false;
                  for (final Class<?> excludeClass : excludedClasses) {
                      if (excludeClass.isAssignableFrom(tempClass)) {
                          excludeIt = true;
                      }
                  }
                  if (!excludeIt) {
                      genericClass = tempClass;
                  }
              }
          }
  
          return genericClass;
      }
docs: Return the generic class for the given parent class and index.
  
  @param mainClass the parent class
  @param excludedClasses if the array contains only one class it define the type of the generic to build, otherwise it defines the types to skip to find the object to build
  
  @return the class of the generic type according to the index provided or null if not found