java二進制格式化高位補0工具類輸出996

java輸出二進制高位補0

	/**整數轉二進制,前面補零*/
    public static String intToBinary(int num){
    	//1.補零
        String binaryStr = Integer.toBinaryString(num);
        int bitNum = 8;
        if(bitNum<binaryStr.length()) {
        	bitNum += bitNum;//不斷翻倍8 16 32 64...
        }
        while(binaryStr.length() < bitNum){
            binaryStr = "0"+binaryStr;
        }
        //2.格式化
		String str = "";
		for (int i = 0; i < binaryStr.length();) {
			str += binaryStr.substring(i, i=i+4)+",";
		}
		return str.substring(0, str.length()-1);
    }

測試

		System.out.println(Integer.toBinaryString(996));
		System.out.println(intToBinary(996));

輸出

1111100100
0000,0011,1110,0100

資料
https://blog.csdn.net/libertine1993/article/details/100876919
https://blog.csdn.net/lonely_fireworks/article/details/7962171