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Re: HttpURLConnection

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On Tuesday, February 19, 2013 4:56:31 PM UTC-6, Eric Sosman wrote:
> On 2/19/2013 4:45 PM, bob smith wrote:
> 
> > How can people use the class HttpURLConnection when the abstract method connect() from URLConnection is never defined?
> 
> >
> 
> > I thought you can't use a class till all the abstract blanks are filled in?
> 
> 
> 
>      The openConnection() method of the URL class returns a
> 
> URLConnection object.  I haven't used it myself, but from the
> 
> documentation it appears that for an HTTP URL the URLConnection
> 
> will in fact be an HttpURLConnection.
> 
> 
> 
>      Both of those classes are abstract, and as such they cannot
> 
> be instantiated.  The object actually returned will be an instance
> 
> of some concrete subclass, possibly anonymous.  The inheritance
> 
> tree would look something like
> 
> 
> 
> 	java.lang.Object
> 
> 	    java.net.URLConnection
> 
> 	        java.net.HttpURLConnection
> 
> 	            (maybe a few more levels here)
> 
> 	                some.concrete.class.Thing
> 
> 
> 
>      If you're curious, you can do getClass() on the object you
> 
> get back from openConnection(), and print its class name or do
> 
> other snoopy things.  But to use it, you're just fine treating
> 
> it as an HttpURLConnection -- because it "is an" HttpURLConnection,
> 
> in exactly the same way that an Integer "is a" Number.
> 
> 
> 
> -- 
> 
> Eric Sosman
> 
> esosman@comcast-dot-net.invalid

Thanks.  This clears up a lot.

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Thread

HttpURLConnection bob smith <bob@coolfone.comze.com> - 2013-02-19 13:45 -0800
  Re: HttpURLConnection Lew <lewbloch@gmail.com> - 2013-02-19 14:31 -0800
  Re: HttpURLConnection Eric Sosman <esosman@comcast-dot-net.invalid> - 2013-02-19 17:56 -0500
    Re: HttpURLConnection bob smith <bob@coolfone.comze.com> - 2013-02-20 10:26 -0800
      Re: HttpURLConnection Arne Vajhøj <arne@vajhoej.dk> - 2013-02-22 13:28 -0500
  Re: HttpURLConnection Roedy Green <see_website@mindprod.com.invalid> - 2013-02-20 22:05 -0800

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