java - XmlRpcClient が URL アドレスを割り当てられない

Question

以下のソースコードをコンパイル中にエラーが発生しました:

import java.util.*;
import org.apache.xmlrpc.client.*; 
import org.apache.xmlrpc.common.*;
import org.apache.xmlrpc.*;
public class pms {
    public static void main (String [] args) {
        String UserName = "123";
        String Password = "123";
        String pKey     = "123";
        XmlRpcClient server = new XmlRpcClient("http://localhost/RPC2"); //("http://localhost/RPC2"); 
        Vector params = new Vector();
      try {
         params.addElement(new Integer(17));
         params.addElement(new Integer(13));
         Object result = server.execute("acquire_token",params);
         int sum = ((Integer) result).intValue();
         System.out.println("The sum is: "+ sum);
      } catch (Exception exception) {
         System.err.println("JavaClient: " + exception);
      }
        System.out.println("Hello World");
  }

}