防止后台响应乱码

public void outJsonString(String str) {
  getResponse().setContentType("text/javascript;charset=UTF-8");
  outString(str);
 }
   
 public void outHtmlString(String str) {
  getResponse().setContentType("text/html;charset=UTF-8");
  outString(str);
 }
 public void outXml(String str) {
  getResponse().setContentType("text/xml;charset=UTF-8");
  outString(str);
 }