进制转换

import java.util.Scanner;

public class TestTransform {
    public static void main(String[] args) {

        
        trans();
    }

//    public static void toBin0(int num) {
//        trans(num, 2);
//    }
//
//    public static void toOcto(int num) {
//        trans(num, 8);
//    }
//
//    public static void toHex0(int num) {
//        trans(num, 16);
//    }

    /**
     * 十进制 --> 二、八、十六进制 综合版本
     * 
     * 由用户进行输入想要转换的数和进制
     * 
     * @param num
     * @param base
     * @param wei
     */
    public static void trans() {
        
        System.out.println("请输入你要转换的十进制数和要转换的进制");
        
        Scanner sc = new Scanner(System.in);
        
        int num = sc.nextInt();
        
        int base = sc.nextInt();
        
        int wei;

        if (num == 0) {
            System.out.println(0);
            sc.close();
            return;
        }

        if (base == 2) {
            wei = 1;
        } else if (base == 8) {
            wei = 3;
        } else if (base == 16) {
            wei = 4;
        }else {
            sc.close();
            return;
        }

        char[] chs = { ‘0‘, ‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘7‘, ‘8‘, ‘9‘, ‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ };

        char[] arr = new char[32];

        int pos = arr.length;

        while (num != 0) {

            int temp = num % base;

            arr[--pos] = chs[temp];

            num = num >>> wei;
        }

        for (int i = pos; i < arr.length; i++) {

            System.out.print(arr[i]);

        }

        System.out.println();
        
        sc.close();
    }
    
    
    

    /**
     * 十进制 --> 二进制
     */
    public static void toBin(int i) {

        StringBuffer sBuffer = new StringBuffer();

        while (i > 0) {
            sBuffer.append(i % 2);
            i = i / 2;
        }
        System.out.println(sBuffer.reverse());// reverse()方法将sBuffer倒置
    }

    /**
     * 十进制 --> 十六进制
     */
    public static void toHex(int i) {

        StringBuffer sBuffer = new StringBuffer();

        for (int j = 0; j < 8; j++) {

            int temp = i % 16;// 或者&15
            if (temp > 9) {
                sBuffer.append((char) (temp - 10 + ‘A‘));
            } else {
                sBuffer.append(temp);
            }
            i = i >>> 4;
        }
        System.out.println(sBuffer.reverse());
    }

    /**
     * 查表法 十进制 --> 二进制
     */
    public static void toBin2(int num) {
        char[] chs = { ‘0‘, ‘1‘ };

        char[] arr = new char[32];
        int pos = arr.length;

        while (num != 0) {
            int temp = num % 2;

            arr[--pos] = chs[temp];

            num = num >>> 1;
        }
        for (int i = pos; i < arr.length; i++) {
            System.out.print(arr[i]);
        }
        System.out.println();
    }

    /**
     * 查表法 十进制 --> 十六进制
     */
    public static void toHex2(int num) {
        char[] chs = { ‘0‘, ‘1‘, ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘7‘, ‘8‘, ‘9‘, ‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘ };

        char[] arr = new char[8];
        int pos = arr.length; // pos 指针

        while (num != 0) {
            int temp = num % 16;

            arr[--pos] = chs[temp];

            num = num >>> 4;
        }
        for (int i = pos; i < arr.length; i++) {
            System.out.print(arr[i]);
        }
    }
}