What Is FileInputStream Class In Java?

The FileInputStream class in Java is part of the java.io package and is used to read data from a file. It allows for reading raw bytes from a file and is typically used for handling binary data or when reading files in a byte-oriented manner (such as images or audio files).

Key Features:

1. Byte-oriented: FileInputStream reads data in the form of bytes rather than characters.
2. Input Stream: It is a subclass of InputStream and provides the read() method to read bytes from a file.
3. Reading files: It is used to read data from files, including binary files, in contrast to FileReader, which is typically used for reading character files.

Commonly Used Methods:

• read(): Reads a single byte of data from the file.
• read(byte[] b): Reads bytes into an array.
• close(): Closes the file and releases any system resources associated with the stream.
• available(): Returns the number of bytes that can be read without blocking.

Example Usage:

import java.io.FileInputStream;
import java.io.IOException;

public class FileInputStreamExample {
    public static void main(String[] args) {
        FileInputStream fis = null;
        try {
            // Creating a FileInputStream to read the file
            fis = new FileInputStream("example.txt");
            int data;
            // Reading the file byte by byte
            while != -1) {
                System.out.print((char) data);  // Printing the byte as a character
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // Always close the stream to release resources
            try {
                if (fis != null) {
                    fis.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

Key Points:

• File Input: Primarily used for reading files, particularly binary data.
• Efficiency: FileInputStream reads data one byte at a time, which can be inefficient for larger files. For improved performance, consider using buffered streams (BufferedInputStream) or reading chunks of data at once.
• Exception Handling: Since file operations can result in errors (e.g., file not found, permissions issue), you should always handle IOException exceptions appropriately.

In conclusion, FileInputStream is a fundamental class for working with file input in Java, especially for reading binary files or when working with raw data at the byte level.

1. data = fis.read( [↩]