java 数据类型判断格式错误 怎么办啊？

Question

import java.util.Scanner;
public class Main {
    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner sc = new Scanner(System.in);
        boolean flag = true;
        while (flag) {
            if(sc.hasNextInt()) {
                System.out.print("int");
                System.out.print(" ");
            }
            else if(sc.hasNextBoolean()) {
                System.out.print("boolean");
                System.out.print(" ");
            }
            else if(sc.hasNextDouble()){
                System.out.print("double");
                System.out.print(" ");
            }
            else if(sc.hasNext()){
                System.out.print("String\n");
            }
             sc.next();  
            //为什么hasnext 需要 next？
            // 结尾空格怎么去掉？
        }
    }
}

![img](https://img-mid.csdnimg.cn/release/static/image/mid/ask/531409143636165.png "=600 #left")

Answer 1

next是接收字符串，如果要去除空格，可以加上trim();方法。