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After you've successfully created a URL object,
you can call the URL object's openConnection
method to get a URLConnection object, or one of its
protocol specific subclasses, e.g.
java.net.HttpURLConnection
You can use this URLConnection object to setup parameters
and general request properties that you may need before connecting.
Connection to the remote object represented by the URL is only initiated
when the URLConnection.connect method is called.
When you do this
you are initializing a communication link
between your Java program and the URL over the network.
For example, the following code opens a connection to the site example.com:
try {
URL myURL = new URL("http://example.com/");
URLConnection myURLConnection = myURL.openConnection();
myURLConnection.connect();
} catch (MalformedURLException e) { // new URL() failed
. . .
} catch (IOException e) { // openConnection() failed
. . .
}
URLConnection object is created every time by calling
the openConnection method of the protocol handler for this URL.
You are not always required to explicitly call the connect
method to initiate the connection. Operations that depend on being connected,
like getInputStream, getOutputStream, etc, will
implicitly perform the connection, if necessary.
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.
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