java - 收到错误消息“java.lang.Error：未解决的编译...”

Question

以下代码中的错误是什么？我找不到错误。但是我收到一条错误消息：

 Exception in thread "main" java.lang.Error: Unresolved compilation problem: at CircleArea.main(CircleArea.java:6)

代码是：

import java.util.Scanner;

public class CircleArea{
   public static void main (String args[])
   {
     Scanner inputFromUser = new Scanner (System.in);
     int radius = inputFromUser.nextInt();

     double Area =Math.PI *radius*radius;

     System.out.println("Area of the circle is : " + Area);
   }     
 }