java 二进制、八进制、十六进制转换

public static void main(string[] args) {
        system.out.println(tobin(6));
        system.out.println(tohex(0));
        system.out.println(tooct(8));
    }
    
    public static string tobin(int num){
        return trans(num,1,1);
    }

    public static string tohex(int num){
        return trans(num,15,4);
    }

    public static string tooct(int num){
        return trans(num,7,3);
    }

    public static string trans(int num, int base, int offset){
        if (num ==0)
            return "0";
        char[] chs = {'0','1','2','3','4','5','6','7','8','9','a','b','c','b','e','f'};
        char[] arr = new char[32];
        int pos=arr.length;
        while (num!=0){
            int temp = num & base;
            arr[--pos]=chs[temp];
            num = num >>> offset;
        }
        stringbuffer stringbuffer = new stringbuffer();
        for (int i = pos; i < arr.length; i++) {
            stringbuffer.append(arr[i]);
        }
        return stringbuffer.tostring();
    }