请问老师在handlerMessage()方法中，while语句写在try块里面就可以正常收到消息，写在try外面就收不到消息，这是什么原因？

@Async
    public void handleMessage() throws IOException, TimeoutException, InterruptedException {
        log.info("settlement开始监听消息队列");
        ConnectionFactory connectionFactory = new ConnectionFactory();
        connectionFactory.setHost("localhost");
        try (Connection connection = connectionFactory.newConnection();
             Channel channel = connection.createChannel();){

            channel.exchangeDeclare("exchange.order.settlement", BuiltinExchangeType.FANOUT,
                    true,false, null);

            channel.queueDeclare("queue.settlement", true, false, false, null);


            channel.queueBind("queue.settlement", "exchange.order.settlement", "key.settlement");

            channel.basicConsume("queue.settlement",true,deliverCallback,consumerTag->{
            });
            while (true) {
                Thread.sleep(1000000);
            }
        }
    }

此时可以正常收到消息。

个人分析原因：
在try块中的语句执行完毕之后，rabbitmq的连接被关闭了

请老师指点！

还有就是这个死循环线程休眠这里的代码，我还不是很理解，希望老师能详细地说明一下，谢谢老师！