java.io
Class FileInputStream

java.lang.Object
  |
  +--java.io.InputStream
        |
        +--java.io.FileInputStream

public class FileInputStream

extends InputStream

File input stream, can be constructed from a file descriptor or a file name.

See Also:

FileOutputStream, File

Constructor Summary

FileInputStream(File file)
Creates an input file from the specified File object.

FileInputStream(FileDescriptor fdObj)

FileInputStream(String name)
Creates an input file with the specified system dependent file name.

Method Summary

int	available() Returns the number of bytes that can be read without blocking.
void	close() Closes the input stream.
protected void	finalize() Closes the stream when garbage is collected.
FileDescriptor	getFD() Returns the opaque file descriptor object associated with this stream.
int	read() Reads a byte of data.
int	read(byte[] b) Reads data into an array of bytes.
int	read(byte[] b, int off, int len) Reads data into an array of bytes.
long	skip(long n) Skips n bytes of input.

Methods inherited from class java.io.InputStream

mark, markSupported, reset

Methods inherited from class java.lang.Object

clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FileInputStream

public FileInputStream(String name)
                throws FileNotFoundException

Creates an input file with the specified system dependent file name.

Parameters:

name - the system dependent file name

Throws:

IOException - If the file is not found.

FileNotFoundException

FileInputStream

public FileInputStream(File file)
                throws FileNotFoundException

Creates an input file from the specified File object.

Parameters:

file - the file to be opened for reading

Throws:

IOException - If the file is not found.

FileNotFoundException

FileInputStream

public FileInputStream(FileDescriptor fdObj)

Method Detail

read

public int read()
         throws IOException

Reads a byte of data. This method will block if no input is available.

Specified by:

read in class InputStream

Returns:

the byte read, or -1 if the end of the stream is reached.

Throws:

IOException - If an I/O error has occurred.

read

public int read(byte[] b)
         throws IOException

Reads data into an array of bytes. This method blocks until some input is available.

Overrides:

read in class InputStream

Parameters:

b - the buffer into which the data is read

Returns:

the actual number of bytes read. -1 is returned if the end of stream is reached.

Throws:

IOException - If an I/O error has occurred.

read

public int read(byte[] b,
                int off,
                int len)
         throws IOException

Reads data into an array of bytes. This method blocks until some input is available.

Overrides:

read in class InputStream

Parameters:

b - the buffer into which the data is read

off - the start offset of the data

len - the maximum number of bytes read

Returns:

the actual number of bytes read. -1 is returned when the end of the stream is reached.

Throws:

IOException - If an I/O error has occurred.

skip

public long skip(long n)
          throws IOException

Skips n bytes of input.

Overrides:

skip in class InputStream

Parameters:

n - the number of bytes to be skipped

Returns:

the actual number of bytes skipped.

Throws:

IOException - If an I/O error has occurred.

available

public int available()
              throws IOException

Returns the number of bytes that can be read without blocking.

Overrides:

available in class InputStream

Returns:

the number of available bytes, which is initially equal to the file size.

IOException

close

public void close()
           throws IOException

Closes the input stream. This method must be called to release any resources associated with the stream.

Overrides:

close in class InputStream

Throws:

IOException - If an I/O error has occurred.

getFD

public final FileDescriptor getFD()
                           throws IOException

Returns the opaque file descriptor object associated with this stream.

Returns:

the file descriptor.

IOException

finalize

protected void finalize()
                 throws IOException

Closes the stream when garbage is collected.

Overrides:

finalize in class Object

IOException