code: public FieldNode getField(String name) {
          ClassNode node = this;
          while (node != null) {
              FieldNode fn = node.getDeclaredField(name);
              if (fn != null) return fn;
              node = node.getSuperClass();
          }
          return null;
      }
docs: Finds a field matching the given name in this class or a parent class.
  
  @param name the name of the field of interest
  @return the method matching the given name and parameters or null