Java写十进制和二进制互转

package com.helong.test;

import java.util.Scanner;

public class Literals {

	public static void main(String[] args) {
		Scanner input = new Scanner(System.in);
		println("请选择您要操作项的编号：");
		println("1.十进制转二进制\t\t\t2.二进制转十进制");
		while (!input.hasNextInt()) {
			println("您输入的不是整型，请输入0-9的数字");
			input.nextLine();
		}
		Scanner input1 = new Scanner(System.in);
		switch (input.nextInt()) {
		case 1:
			println("\t\t\t\t您选择的是：1.十进制转二进制");
			println("请输入你要转换的二进制数:");
			int a = 0;
			a = input1.nextInt();
			println("您输入的十进制数是：" + a + " 转换成二进制是：" + convertBinary(a));
			break;
		case 2:
			println("\t\t\t\t您选择的是：2.二进制转十进制");
			println("请输入你要转换的二进制数:");
			String b = input1.nextLine();
			println("您输入的二进制数是：" + b + " 转换成十进制数是："
					+ convertAlgorism(b.toCharArray()));
			break;
		default:

			println("您输入的操作编号系统不能识别，系统将自动停止");
		}
		input.close();
	}

	// 十进制转换二进制
	private static String convertBinary(int sum) {
		StringBuffer binary = new StringBuffer();
		while (sum != 0 && sum != 1) {
			binary.insert(0, sum % 2);
			println("sum=" + sum + "余数=" + (sum % 2) + "除数=" + sum / 2);
			sum = sum / 2;
			if (sum == 0 || sum == 1) {
				binary.insert(0, sum % 2);
			}
		}
		return binary.toString();
	}

	// 二进制转十进制
	private static int convertAlgorism(char[] cars) {
		int result = 0;
		int num = 0;
		for (int i = cars.length - 1; 0 <= i; i--) {
			int temp = 2;
			if (num == 0) {
				temp = 1;
			} else if (num == 1) {
				temp = 2;
			} else {
				for (int j = 1; j < num; j++) {
					temp = temp * 2;
				}
			}
			int sum = Integer.parseInt(String.valueOf(cars[i]));
			result = result + (sum * temp);
			num++;
		}

		return result;
	}

	private static void println(Object info) {
		System.out.println(info);
	}

	private static void print(Object info) {
		System.out.print(info);
	}
}

今天抽空研究了下十进制转换二进制的规则，然后写成代码，望观看的朋友，给出意见，小弟不胜感激