How to understand the “synchronous” and “asynchronouns” messaging in JMS?

Question

After reading some document of JMS, I totally puzzled by the phrase synchronous and asynchronouns.

See this page: http://docs.oracle.com/cd

Answer 1

Like I understand this:

asynchronous - MessageListener: Use this on a server that listens to a queue. When a message arrives, then deal with it immediately. The server keeps listening to this queue.

synchronous - consumer.receive(1000): Use this on a client applications that now and then needs to check if a message is intend for this client. Example: poll every 60 seconds. This only opens a connection to the server shortly. The 1000 milliseconds will keep this connection open. If a message arrives within these 1000 milliseconds, then the message is consumed and the connection is closed.