Struts 2：如何将 JSON 发送到操作

<struts>
 <package name="json" extends="struts-default">
   <action name="sendJson" class="com.example.SendJsonAction">
     <result type="json">
       <param name="root">jsonResult</param>
      </result>
    </action>
  </package>
</struts>

public class SendJsonAction extends ActionSupport {
  private Map<String, Object> jsonResult;

  public String execute() {
    jsonResult = new HashMap<String, Object>();
    jsonResult.put("name", "John Doe");
    jsonResult.put("age", 30);
    jsonResult.put("city", "New York");

    return SUCCESS;
  }

  public Map<String, Object> getJsonResult() {
    return jsonResult;
  }
}

$.ajax({
  url: "sendJson",
  type: "POST",
  dataType: "json",
  success: function(response) {
    console.log(response);
  }
});