I have answered it right based on it can u edit that by adding the access of writing the data into file — Bhanu. Add a comment. I am just posting my answer because just to download a empty file who need for the beginners. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Podcast Making Agile work for data science. Stack Gives Back Featured on Meta.
New post summary designs on greatest hits now, everywhere else eventually. Related Hot Network Questions. Question feed. Stack Overflow works best with JavaScript enabled. Here is the simple java download file from URL example program. It shows both ways to download file from URL in java. Then we are using a file output stream to read data from the input stream and write to the file.
Then use the file output stream to write it to file. You can use any of these methods to download the file from URL in java program. If you are looking for performance, then do some analysis by using both methods and see what suits your need. Thanks Pankaj for a very good example, explained is few simple steps.
However, since I am a beginner in the field, I still cant apply the example to real exercise, I am trying to solve. Please, I need your assistance as soon as you can. Have tried with other few examples but cant just complete it. Hello sir, Actually I want to download.
I went through this code with different URL but it throws the following exception could you please help me out with this problem. The server might be blocking it, can you try after setting the User-Agent header?
That way, it will look like the request is coming from a browser. If I execute the same example I am getting below exception java. ConnectException: Connection timed out: connect at java. Before we dive deeper into the coding aspect let's take an overview of the classes and the individual functions we will be using in the process. The java. 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. After defining the file channel we will use the transferFrom method to copy the contents read from the readChannel object to the file destination using the writeChannel object. The transferFrom and transferTo methods are much more efficient than working with streams using a buffer.
The transfer methods enable us to directly copy the contents of the file system cache to the file on the system. Thus direct channeling restricts the number of context switches required and enhances the overall code performance.
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