Closing a Java FileInputStream
A FileInputStream is a useful tool for reading data from a file in a Java program. However, as with any resource, it is important to properly close the FileInputStream when it is no longer needed. In this article, we will discuss why it is important to close a FileInputStream and how to do it properly.
Why is it important to close a FileInputStream?
A FileInputStream is a resource that is used to read data from a file. It is important to close this resource when it is no longer needed because it frees up system resources and prevents memory leaks. If a FileInputStream is not closed, it can lead to errors in the program or even cause the program to crash. Additionally, if the program is running for a long time and opening multiple FileInputStreams without closing them, it can lead to the depletion of system resources and impact the performance of the system.
How to close a FileInputStream?
Closing a FileInputStream is a simple process. The FileInputStream class has a method called "close()" which can be used to close the stream. It is important to call this method at the end of the program or when the stream is no longer needed. For example, if the FileInputStream is used in a try-with-resources block, it will automatically close the stream at the end of the block.
Here's an example of how to use the close() method to close a FileInputStream:
try (FileInputStream fis = new FileInputStream("myFile.txt")){
//code to read data from the file
} catch (IOException e) {
e.printStackTrace();
}
In the above code, the FileInputStream is declared and initialized in the try block, and the close() method is automatically called at the end of the block.
What happens if a FileInputStream is not closed?
If a FileInputStream is not closed, it will continue to hold on to resources even after it is no longer needed. This can lead to memory leaks and affect the performance of the program. In some cases, it can also cause the program to crash. Additionally, if the program is running for a long time and opening multiple FileInputStreams without closing them, it can lead to the depletion of system resources and impact the performance of the system.
Tips for closing a FileInputStream
1. Always close the FileInputStream when it is no longer needed, preferably in a finally block.
2. If the FileInputStream is used in a try-with-resources block, it will automatically close the stream at the end of the block.
3. Use a try-catch block to catch any exceptions that may occur when closing the stream.
4. Make sure to close the FileInputStream even if an exception occurs while reading the data from the file.
5. Do not rely on the garbage collector to close the FileInputStream, as it may not happen immediately.
In conclusion, closing a FileInputStream is an important step in managing system resources and preventing memory leaks in a Java program. It is a simple process that can be easily overlooked, but can have a significant impact on the performance and stability of the program. By following the tips mentioned in this article, you can ensure that your FileInputStreams are properly closed and your program runs smoothly.
