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Trail: Custom Networking
Lesson: Working with URLs
Working with URLs
What Is a URL?
Creating a URL
Parsing a URL
Reading Directly from a URL
Connecting to a URL
Reading from and Writing to a URLConnection
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Connecting to a URL

> 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, 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();
> >         yahooConnection.connect();

> >     } catch (MalformedURLException e) {     // new URL() failed
> >         . . .
> >     } catch (IOException e) {               // openConnection() failed
> >         . . .
> >     }

> A new `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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