java-10进制转16进制

方法一：

调用Integer中的进制转换方法：
String hex = Integer.toHexString(15);//f

方法二：

public static String numToHex(Integer num){
        char[] m = new char[16];
        for (int i = 0; i < 10; i++) {
            m[i] = (char) (i + '0');
        }
        for (int i = 10; i < 16; i++) {
            m[i] = (char) ('A' + (i - 10));
        }
        String str = "";
        while (num != 0) {
            str = m[num % 16] + str;
            num = num / 16;
        }
          return str;
    }

    public static void main(String[] args) {
    	Random random=new Random();
    	int i2 = random.nextInt(899999) + 100001;//0-999999
    	String s = NumUtils.numToHex(i2 );
    	System.out.println(s);
    }