receive()方法从main()方法中调用，它依次打开你的POP3信箱检查消息，每次都调用printMessage()。代码如下：
/**
* "receive" method to fetch messages and process them.
*/
public static void receive(String popServer, String popUser
, String popPassWord)
{
Store store=null;
Folder folder=null;
try
{
// -- Get hold of the default session --
Properties props = System.getProperties();
Session session = Session.getDefaultInstance(props, null);
// -- Get hold of a POP3 message store, and connect to it --
store = session.getStore("pop3");
store.connect(popServer, popUser, popPassword);
// -- Try to get hold of the default folder --
folder = store.getDefaultFolder();
if (folder == null) throw new Exception("No default folder");
// -- ...and its INBOX --
folder = folder.getFolder("INBOX");
if (folder == null) throw new Exception("No POP3 INBOX");
// -- Open the folder for read only --
folder.open(Folder.READ_ONLY);
// -- Get the message wrappers and process them --
Message[] msgs = folder.getMessages();
for (int msgNum = 0; msgNum < msgs.length; msgNum++)
{
printMessage(msgs[msgNum]);
}
}
catch (Exception ex)
{
ex.printStackTrace();
}
finally
{
// -- Close down nicely --
try
{
if (folder!=null) folder.close(false);
if (store!=null) store.close();
}
catch (Exception ex2) {ex2.printStackTrace();}
}
} （出处：http://www.knowsky.com）