自定义UUID算法

  private static final String ALLOWED_CHARS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
    private static final int UUID_LENGTH = 36;
 
    public static String generateUUID() {
        StringBuilder uuidBuilder = new StringBuilder(UUID_LENGTH);
        Random random = new Random();
 
        for (int i = 0; i < UUID_LENGTH; i++) {
            if (i == 8 || i == 13 || i == 18 || i == 23) {
                uuidBuilder.append('-');
            } else {
                uuidBuilder.append(ALLOWED_CHARS.charAt(random.nextInt(ALLOWED_CHARS.length())));
                System.out.println(uuidBuilder+"[][][][][][][][][][][][][][]");
            }
        }
 
        return uuidBuilder.toString();
    }
 
    public static void main(String[] args) {
        String customUUID = generateUUID();
        System.out.println(customUUID);
    }