Struts 2 button com ajax [RESOLVIDO]

function correctAnswer(){
		$.ajax({
		    url: '/lingle/correctExercise',
		    success: function(data) {
		       var message = data.updateResultMessage;
		       alert('The message is '+message);
		    }
		});
	}


<a href="#" onclick="correctAnswer()">Check Answer</a>

<action name="correctExercise" class="lingle.front.web.ExerciseConfig" method="correctExercise">			
			<result type="json"/>
		</action>

public String correctExercise(){
		try {
			ExerciseGrammarGaps exercise = (ExerciseGrammarGaps) WebSessionUtil.get("exercise");
			if(exercise.getCorrectWordList() != null){
		
				Map mapRequest = servletRequest.getParameterMap();
				
				ArrayList<String> newCorrectwordList = new ArrayList<String>();
				for(String correctWords : exercise.getCorrectWordList().split("[|]")){
					for(String word : correctWords.trim().split(" ")){
						newCorrectwordList.add(word);
					}
				}
				
				int correctAnswer = 0;
				
				for(int count = 0; count < newCorrectwordList.size(); count++){
					String[] answer  = (String[])mapRequest.get("txtWord"+count);
					
					if(answer != null && newCorrectwordList.get(count).equals(answer[0])){
						correctAnswer++;
					}
				}
				
				if(correctAnswer == newCorrectwordList.size()){
					this.setUpdateResultMessage("<p class = \"result_success_message\">Your score is 100%. Well done!</p>");
				}else{
					int percent = (correctAnswer) * 100 / newCorrectwordList.size(); 
					
					this.setUpdateResultMessage("<p class = \"result_failure_message\">Your score is "+percent+"%. Try again!</p>");
				}
			}else{
				this.setUpdateResultMessage("<p class = \"result_failure_message\">There isn't a list of correct words for this exercise.</p>");
			}
		} catch (Exception e) {
			e.printStackTrace();
		}				
		
		return "success";
	}