如何使Integer.toBinaryString返回至少4位

public class Main {
    public static void main(String[] args) {
        int num = 5;
        String binaryString = Integer.toBinaryString(num);
        String formattedBinaryString = String.format("%4s", binaryString).replace(' ', '0');
        System.out.println("原始二进制字符串: " + binaryString);
        System.out.println("格式化后的二进制字符串: " + formattedBinaryString);
    }
}