After you've successfully created a URL
object,
you can call the URL
object's openConnection
method to connect to it.
When you connect to a URL
,
you are initializing a communication link
between your Java program and the URL over the network.
For example, you can open a connection to the Yahoo site
with the following code:
try {
URL yahoo = new URL("http://www.yahoo.com/");
URLConnection yahooConnection = yahoo.openConnection();
} catch (MalformedURLException e) { // new URL() failed
. . .
} catch (IOException e) { // openConnection() failed
. . .
}
If possible, the openConnection
method creates
a new URLConnection
(if an appropriate one does not already exist),
initializes it, connects to the URL,
and returns the URLConnection
object.
If something goes wrong--for example,
the Yahoo server is down--then the openConnection
method throws an IOException.
Now that you've successfully connected to your URL, you can use the
URLConnection
object to perform actions
such as reading from or writing
to the connection. The next section shows you how.