编辑代码

import java.util.regex.Matcher;
import java.util.regex.Pattern;

class Main {
	public static void main(String[] args) {
        Pattern KEY_PATTERN = Pattern.compile("^【[^】]*(】)");
        String test = "收信白名单未绑定：【抖音】您购买的[点餐]【可外卖】芝士奶盖茶二选一【春季特惠】test";
        Matcher matcher = KEY_PATTERN.matcher(test);
        if (matcher.find()) {
            String whiteKey = matcher.group(0);
            System.out.println(whiteKey);
        }
        else {
            System.out.println("没有匹配内容");
        }
	}
}