Servlet蛋疼的编码问题

servlet都说设置了request.setCharacterEncoding("UTF-8")编码就不会出错（utf-8 指所用的编码方法）接受request参数的变量还得再者之前设置

例如：

String title;
String content;
 try {
   request.setCharacterEncoding("UTF-8");
   
    title=request.getParameter("title");
    content=request.getParameter("content");

     } catch (UnsupportedEncodingException e1) {
   // TODO Auto-generated catch block
   e1.printStackTrace();
  }

此时将不会出现乱码

但是

  

try {
   request.setCharacterEncoding("UTF-8");
   
   String title=request.getParameter("title");
    String content=request.getParameter("content");

     } catch (UnsupportedEncodingException e1) {
   // TODO Auto-generated catch block
   e1.printStackTrace();
  }

这样便会出现乱码