java判断用户输入的数据类型 1publicclassDemo1 {2publicstaticvoidmain(String[] args) {3Scanner input =newScanner(System.in);4System.out.println("请输入一个数字:");5if(input.hasNextInt()) {6intnum =input.nextInt();7System.out.println("你输入的是:"+num);8}else{9System.out.println("你...