org.fuin.utils4j
Class RandomAccessFileInputStream

java.lang.Object
  java.io.InputStream
      org.fuin.utils4j.RandomAccessFileInputStream

All Implemented Interfaces:

Closeable

public final class RandomAccessFileInputStream
extends InputStream

A random access based file input stream. The readlimit argument of the mark(int) method is ignored (there is no limit).

Constructor Summary

RandomAccessFileInputStream(File file, String mode)
Constructor with file.

RandomAccessFileInputStream(RandomAccessFileInputStream in)
Constructor with input stream.

RandomAccessFileInputStream(RandomAccessFileOutputStream out)
Constructor with output stream.

Method Summary

int	available()
void	close()
long	fileSize() Returns the size of the underlying file.
FileChannel	getChannel() Returns the channel used by the random access file.
FileLock	lock(int tryLockMax, long tryWaitMillis) Lock the file.
void	mark(int readlimit)
boolean	markSupported()
int	read()
int	read(byte[] b)
int	read(byte[] b, int off, int len)
void	reset()
void	seek(long pos) Sets the file-pointer offset, measured from the beginning of this file, at which the next read or write occurs.
long	skip(long n)

Methods inherited from class java.lang.Object

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

Constructor Detail

RandomAccessFileInputStream

public RandomAccessFileInputStream(File file,
                                   String mode)
                            throws FileNotFoundException

Constructor with file.

Parameters:

file - File the stream operates on - Cannot be null.

mode - Access mode, as described in RandomAccessFile - Cannot be null.

Throws:

FileNotFoundException - If the mode is "r" but the given file object does not denote an existing regular file, or if the mode begins with "rw" but the given file object does not denote an existing, writable regular file and a new regular file of that name cannot be created, or if some other error occurs while opening or creating the file.

RandomAccessFileInputStream

public RandomAccessFileInputStream(RandomAccessFileInputStream in)

Constructor with input stream. The new stream shares the RandomAccessFile with the argument. Be aware that closing this stream will also close the file used by the argument!

Parameters:

in - The RandomAccessFile instance from this argument will be used - Cannot be null.

RandomAccessFileInputStream

public RandomAccessFileInputStream(RandomAccessFileOutputStream out)

Constructor with output stream. The new stream shares the RandomAccessFile with the argument. Be aware that closing this stream will also close the file used by the argument!

Parameters:

out - The RandomAccessFile instance from this argument will be used - Cannot be null.

Method Detail

read

public final int read()
               throws IOException

Specified by:

read in class InputStream

Throws:

IOException

read

public final int read(byte[] b)
               throws IOException

Overrides:

read in class InputStream

Throws:

IOException

read

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

Overrides:

read in class InputStream

Throws:

IOException

skip

public final long skip(long n)
                throws IOException

Overrides:

skip in class InputStream

Throws:

IOException

fileSize

public final long fileSize()
                    throws IOException

Returns the size of the underlying file.

Returns:

Number of bytes.

Throws:

IOException - IOException if an I/O error occurs.

available

public final int available()
                    throws IOException

Overrides:

available in class InputStream

Throws:

IOException

close

public final void close()
                 throws IOException

Specified by:

close in interface Closeable

Overrides:

close in class InputStream

Throws:

IOException

mark

public void mark(int readlimit)

Overrides:

mark in class InputStream

reset

public final void reset()
                 throws IOException

Overrides:

reset in class InputStream

Throws:

IOException

markSupported

public final boolean markSupported()

Overrides:

markSupported in class InputStream

getChannel

public final FileChannel getChannel()

Returns the channel used by the random access file.

Returns:

Channel.

seek

public final void seek(long pos)
                throws IOException

Sets the file-pointer offset, measured from the beginning of this file, at which the next read or write occurs. The offset may be set beyond the end of the file. Setting the offset beyond the end of the file does not change the file length. The file length will change only by writing after the offset has been set beyond the end of the file.

Parameters:

pos - the offset position, measured in bytes from the beginning of the file, at which to set the file pointer.

Throws:

IOException - if pos is less than 0 or if an I/O error occurs.

lock

public final FileLock lock(int tryLockMax,
                           long tryWaitMillis)
                    throws LockingFailedException

Lock the file.

Parameters:

tryLockMax - Number of tries to lock before throwing an exception.

tryWaitMillis - Milliseconds to sleep between retries.

Returns:

FileLock.

Throws:

LockingFailedException - Locking the file failed.