例子：
struts.xml:
a.action:
private String value1;
private String value2;
private String text;
get()...set()...
public void test()throws Exception{
//do somethings
HttpServletResponse response = ServletActionContext.getResponse();
response.setContentType("application/json;charset=UTF-8");
response.setCharacterEncoding("UTF-8");
try{
PrintWriter pw = response.getWriter();
boolean flag = XXXService(value1,value2);
String text = "";
if(flag)
text = "执行成功!";
else
text = "执行失败!";
pw.write(text);
pw.flush();
}catch(Exception e){
e.printStackTrace();
throw new Exception("执行异常!");
}
}
