线程“main”中的异常 java.lang.Error：未解决的编译问题：
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时间：2020-08-13 17:30:51 来源:igfitidea点击:
Exception in thread "main" java.lang.Error: Unresolved compilation problems:
提问by user3475322
This is the error I'm getting
这是我得到的错误
Exception in thread "main" java.lang.Error: Unresolved compilation problems:
Scanner cannot be resolved to a type
Scanner cannot be resolved to a type
at hello.main(hello.java:11)
This is my code.
这是我的代码。
public class hello {
public static void main(String[] args) {
// TODO Auto-generated method stub
double area;
double radius;
Scanner input = new Scanner(System.in);
System.out.print("???? ?????: ");
radius = input.nextDouble();
area = 3.14 * radius * radius;
System.out.println(area);
}
}
采纳答案by SpringLearner
Have you imported Scanner class like import java.util.Scanner;
您是否导入了 Scanner 类 import java.util.Scanner;
回答by SpringLearner
You need:
你需要：
import java.util.Scanner;
at the top of your file. You've got to import it.
在文件的顶部。你必须导入它。
