Java、十进制转十六进制

编写一个程序，提示用户输入 0 ~ 15 之间的一个整数，显示其对应的十六进制数。

package pack2;

import java.util.Scanner;

public class Tranmission {

	public static void main(String[] args) {
		try(Scanner input = new Scanner(System.in);) {
			System.out.print("Enter a decimal value (0 to 15): ");
			int value = input.nextInt();
			
			System.out.println((0 <= value && value <= 15) ? 
                "The hex value is "+hexValue(value) : value+" is an invalid input");
		}
	}

	//十进制转十六进制
	public static String hexValue(int value) {
		if(0 <= value && value <= 9)	//如果为0 - 9 的数字，直接返回
			return String.valueOf(value);
		
		String hex = "";
		switch(value) {	//处理10 - 15 的数字
		case 10: hex = "A"; break;
		case 11: hex = "B"; break;
		case 12: hex = "C"; break;
		case 13: hex = "D"; break;
		case 14: hex = "E"; break;
		case 15: hex = "F"; break;
		}
		return hex;
	}
}