java十进制到（二进制，八进制，十六进制）的转换的优化

import java.util.Scanner;

public class ArrayTest {

    public static void main(String[] args) {
        int n, m;
        Scanner cin = new Scanner(System.in);
        n = cin.nextInt();
        m = cin.nextInt();
        toBin(n);
        toHex(m);
    }

    public static void toBin(int n) {// 十进制--->二进制
        tran(n, 1, 1);
    }

    public static void toHex(int n) {// 十进制--->十六进制
        tran(n, 15, 4);
    }

    public static void toBa(int n) {// 十进制--->八进制
        tran(n, 7, 3);
    }

    public static void tran(int n, int base, int offest) {
        if (n == 0) {
            System.out.println(0);
            return;
        }
        char[] ch = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A',
                'B', 'C', 'D', 'E', 'F' };
        char[] str = new char[100];
        int pos = str.length;
        while (n != 0) {
            int temp = n & base;
            str[--pos] = ch[temp];
            n = n >>> offest;

        }
        for (int i = pos; i < str.length; i++) {
            System.out.println(str[i]);
        }
    }

}