三种format格式

public static void main(String[] args) {

        Exception e = new Exception();
        LOGGER.error("处理异常{}", "[main方法]", e);


        String s = MessageFormat.format("hello{0}","[MAIN]");
        System.out.println(s);

        System.out.printf("%s %<s %s %<s","a","b");

    }