code: @SuppressWarnings({ "unchecked", "rawtypes" })
      public List serialize(ClassUnwrapper unwrapper, Object agent) {
  	    List variables = new ArrayList<>();
  	    List<GetterMethodCover> methods = unwrapper.getMethods();
  	    for(GetterMethodCover method : methods) {
  	        Object value = method.invoke(agent);
  	        if(value == null)
  	            continue;
              variables.add(newVariable(method.getKey(), 
                      getValue(method, value), 
                      method.isHidden()));
  	    }
  	    return variables;
  	}
docs: Serialize java object
  
  @param unwrapper structure of agent class
  @param agent the agent object
  @return List of variables