ajax后台处理响应（java）

public static final void sendAsJson(HttpServletResponse response, String str)
{
  response.setContentType("application/json;charset=UTF-8");
  if (null != str)
    try {
      response.getWriter().write(str);
    } catch (IOException e) {
      e.printStackTrace();
    }
}  

public static final void sendAsText(HttpServletResponse response, String str)
{
  response.setContentType("text/html;charset=UTF-8");
  if (null != str)
    try {
      response.getWriter().write(str);
    } catch (IOException e) {
      e.printStackTrace();
    }
}