URL class in Java is a built-in library that offers multiple methods to access and manipulate data on the internet. In this case, we will be using the openStream function of the URL class. The method signature for the openStream function is:. The openStream function works on an object of the URL class. The URL class opens up a connection to the given URL and the openStream method returns an input stream which is used to read data from the connection. These classes are used for reading from a file and writing to it, respectively.
The contents are read as bytes and copied to a file in the local directory using the FileOutputStream. To lower the number of lines of code we can use the Files class available from Java 7. The Files class contains methods that read all the bytes at once and then copies it into another file. Here is how you can use it:. Java NIO is an alternative package to handle networking and input-output operations in Java. The main advantage that the Java NIO package offers is that it's non-blocking, and has channeling and buffering capabilities.
When we use the Java IO library we work with streams that read data byte by byte. However, the Java NIO package uses channels and buffers.
The buffering and channeling capabilities allow the system to copy contents from a URL directly into the intended file without needing to save the bytes in application memory, which would be an intermediary step. The ability to work with channels boosts performance. The downloaded contents will be transferred to a file on the local system via the corresponding file channel. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown.
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The best solution ever but I would like to add 1 important line 'client. Though I think that WebClient seems like a much more straightforward and simple solution. DownloadFileTaskAsync new Uri " somesite. Show 2 more comments. Include this namespace using System.
Abdul Saleem Abdul Saleem 8, 4 4 gold badges 38 38 silver badges 37 37 bronze badges. The question asks for the simplest way. Making more complicated isn't making it the simplest. Most people would prefer a progress bar while downloading.
So i just wrote the simplest way to do that. This might not be the answer but it meets the requirement of Stackoverflow. That is to help someone. This is just as simple as the other answer if you just leave out the progress bar. Also the question doesn't ask for the simplest way, just a simple way. Jessedegans There is already an answer that shows how to simply download without a progressbar. Thats why I wrote an answer that helps with asynchronous download and progressbar implementation — Abdul Saleem.
This answer is good, probably better and more detailed than the one with more upvotes. It's almost obvious that one needs a progress indicator while downloading a file. The asynchronous functionality is a bonus. I was looking for such an implementation.
Show 1 more comment. Chris Lee 6 6 bronze badges. WebClient is obsolete see github. Welcome to SO! Generally it's not a good idea to post a low-quality answer to an existing and old question that already has highly upvoted answers. I found my answer from seanb's comment, but truly I prefer this "low-quality" answer over the others. It's complete using statement , concise and easy to understand.
Being an old question is irrelevant, IMHO. But it think the answer with Using is much better, because, i think the WebClient should be disposed after used. Putting it inside using ensures that it is disposed. It has nothing to do with dispose in this code example The using statement here just show the namespace to use, no that WebClient is use into using to be dispose Complete class to download a file while printing status to console.
ComponentModel; using System. IO; using System. Net; using System. Asked 7 years, 4 months ago. Active 6 days ago. Viewed k times. Improve this question. Uwe Keim Ifwat Ibrahim Ifwat Ibrahim 1, 4 4 gold badges 15 15 silver badges 28 28 bronze badges. Add a comment. Active Oldest Votes. Simply You can use following methods. Flush ; stream. Close ; client. Improve this answer. Adi Kusuma 15 1 1 silver badge 4 4 bronze badges.
Charlie Charlie 4, 1 1 gold badge 28 28 silver badges 52 52 bronze badges. Arsman Ahmad that's a completely different question that should be looked for or asked elsewhere.
This thread is for the downloading of a single image. Perfect28 Perfect28 Note that you need "using System. Drawing;" for Image. FromStream — dlchambers. Note that instead of asking the imaging library to detect the image format you can also look at the response headers to see what format the source thinks the image is using webClient. ResponseHeaders["Content-Type"] — bikeman This would also be much more memory efficient than expanding the compressed image into an uncompressed Bitmap object, and would allow you to save the image in its original format with its original compression etc.
Eric Aya Brian Cryer Brian Cryer 1, 13 13 silver badges 17 17 bronze badges. NET has changed a bit over the years, making the other answers on this post pretty dated: They use Image from System.
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