Managing Input/Output Files in Java
The FileInputStream class
|• Is part of the java.io package|
|• Is an extension of the InputStream class, an abstract class that describes the behavior of an input stream|
|• Is a low-level class that can be used to read individual, 8-bit bytes from a stream|
|• Has several constructors. The most frequently used constructs a FileInputStream object from a File object that encapsulates the file's pathname. For example, if fd is the reference of a File object|
|FileInputStream in = new FileInputStream(fd);|
|It will construct a FileInputStream object for reading bytes from the file. Because a checked, IOException may occur, the statement should be enclosed in a try block with an appropriate catch.|
|• it has a few useful methods. The most used are:|
|Because a checked, IOException may occur, calls to these methods should be enclosed in a try block with an appropriate catch. Consult the Java API documentation for more details.|
|• Example. The following program can be used to read byte values from a disk file. It can be used to display the values stored by the previous sample program.|
public class AppFIS
public static void main(String args)
// Local variables and object references.
// Get the path name from the user.
System.out.print("Enter the file's complete path name: ");
fd = new File(Keyboard.readString());
// Try to read data from the input stream.
// Open an input stream for the file.
in = new FileInputStream(fd);
// This loop reads a byte from the stream and displays
// its value. The loop ends when no more bytes are available.
while (in.available() > 0)
// Close the stream.
System.out.println("Closed - " + fd.getPath());
// Catch an IOException if one is thrown.
catch (IOException e)