How can Java determine if the input number is an intege…

In Java, you can use the following method to determine if the input number is an integer:

1. Get input numbers using the Scanner class.

Scanner scanner = new Scanner(System.in);
System.out.print("请输入一个数字：");
double number = scanner.nextDouble();

1. Use the round method of the Math class to round the input number to the nearest integer.

int roundedNumber = (int) Math.round(number);

1. Compare the original number with its rounded integer to determine if the input number is an integer.

if (number == roundedNumber) {
    System.out.println("输入的数字是整数。");
} else {
    System.out.println("输入的数字不是整数。");
}

Here is the complete example code:

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("请输入一个数字：");
        double number = scanner.nextDouble();
        
        int roundedNumber = (int) Math.round(number);
        
        if (number == roundedNumber) {
            System.out.println("输入的数字是整数。");
        } else {
            System.out.println("输入的数字不是整数。");
        }
    }
}

With the above method, it is possible to determine if the input number is an integer.