Fileoutputstream write large file

We have tried a various ways of reading and writing very large files in Java. In this section we will discuss their performance and understand which one is the optimal way of large file handling in Java. As stated earlier, the in memory transfer is a fast way of data transfer. It can easily exhaust all available memory when a file is very large, or the application is serving multiple such requests simultaneously.

In the Java Stream example of processing large files, we generated Stream of lines using BufferedReader , which produced a descent result. Similarly, example Java FileScanner to transfer large files turned out better on the memory. However, both of these transfer were really slow. We have also seen examples of using FileChannel and BufferedInputStream to read and write very large files. At the base of both examples, we used a buffer of a fixed size.

Both of these ways demonstrated better performance in terms of speed and low memory consumption. Moreover, we can still improve the performance of these two ways by using larger buffers. Because, larger buffers means lesser interactions with underlying files.

However, larger buffers also means larger consumption of memory. To prove that we will rerun both of these examples with a buffer size of or 1MB.

From both of the outputs above we can see a performance improvement, with a slightly more impact on the memory. Last Updated : 25 Jun, FileOutputStream output. Attention reader! Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready. Recommended Articles. Article Contributed By :. Easy Normal Medium Hard Expert. Writing code in comment?

Please use ide. Load Comments. The typical usage for appending is logging. The second parameter of FileOutputStream indicates that we will append to the file. FileWriter class, which is a Java convenience class for writing character files, has a serious limitation: it uses the default encoding and does not allow us to explicitly specify the encoding. Implements the write method of OutputStream.

Specified by: write in class OutputStream Parameters: b - the byte to be written. Overrides: write in class OutputStream Parameters: b - the data. See Also: OutputStream. This file output stream may no longer be used for writing bytes. If this stream has an associated channel then the channel is closed as well. Returns: the FileDescriptor object that represents the connection to the file in the file system being used by this FileOutputStream object.

The initial position of the returned channel will be equal to the number of bytes written to the file so far unless this stream is in append mode, in which case it will be equal to the size of the file. Writing bytes to this stream will increment the channel's position accordingly. Changing the channel's position, either explicitly or by writing, will change this stream's file position.

Returns: the file channel associated with this file output stream Since: 1. See Also: FileInputStream. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

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