url地址的编码和解码问题

public class Hello {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub

String url = "http://www.google.com?id=789&name=中国&hello=&&**()";
String tt=null;


try {
tt=URLEncoder.encode(url, "UTF-8");
System.out.println(tt);
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

System.out.println(tt);
System.out.println(url);
try {
System.out.println(URLDecoder.decode(tt, "UTF-8"));
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}


}