Package org.fairdatapipeline.file

Class CleanableFileChannel

java.lang.Object

org.fairdatapipeline.file.CleanableFileChannel

All Implemented Interfaces:

Closeable, AutoCloseable, ByteChannel, Channel, GatheringByteChannel, ReadableByteChannel, ScatteringByteChannel, SeekableByteChannel, WritableByteChannel

public class CleanableFileChannel
extends Object
implements AutoCloseable, SeekableByteChannel, GatheringByteChannel, ScatteringByteChannel

Wrapper around standard FileChannel with additional safety net for closing if user does not close and ability to run custom function during cleanup/closing. Users should either use with try-with-resources or ensure they manually call .close() once finished. As a safety net, .close() will be called by a cleaner if and when the instance of CleanableFileChannel is going to be collected by GC.

Constructor Summary

Constructors

Constructor	Description
CleanableFileChannel(FileChannel fileChannel, Runnable runOnClose)	Create a filechannel with a runnable closer to perform the close action.

Method Summary

Modifier and Type	Method	Description
void	close()
void	force(boolean metaData)
boolean	isOpen()
FileLock	lock(long position, long size, boolean shared)
MappedByteBuffer	map(FileChannel.MapMode mode, long position, long size)
long	position()
CleanableFileChannel	position(long newPosition)
int	read(ByteBuffer dst)
long	read(ByteBuffer[] dsts)
long	read(ByteBuffer[] dsts, int offset, int length)
int	read(ByteBuffer dst, long position)
long	size()
long	transferFrom(ReadableByteChannel src, long position, long count)
long	transferTo(long position, long count, WritableByteChannel target)
CleanableFileChannel	truncate(long size)
FileLock	tryLock(long position, long size, boolean shared)
int	write(ByteBuffer src)
long	write(ByteBuffer[] srcs)
long	write(ByteBuffer[] srcs, int offset, int length)
int	write(ByteBuffer src, long position)

Methods inherited from class java.lang.Object

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

Constructor Details

CleanableFileChannel

public CleanableFileChannel(FileChannel fileChannel,
 Runnable runOnClose)

Create a filechannel with a runnable closer to perform the close action.

Parameters:

fileChannel - the fileChannel to wrap around.

runOnClose - the runnable to run upon close.

Method Details

read

public int read(ByteBuffer dst)
         throws IOException

Specified by:

read in interface ReadableByteChannel

Specified by:

read in interface SeekableByteChannel

Throws:

IOException

read

public long read(ByteBuffer[] dsts,
 int offset,
 int length)
          throws IOException

Specified by:

read in interface ScatteringByteChannel

Throws:

IOException

read

public long read(ByteBuffer[] dsts)
          throws IOException

Specified by:

read in interface ScatteringByteChannel

Throws:

IOException

write

public int write(ByteBuffer src)
          throws IOException

Specified by:

write in interface SeekableByteChannel

Specified by:

write in interface WritableByteChannel

Throws:

IOException

write

public long write(ByteBuffer[] srcs,
 int offset,
 int length)
           throws IOException

Specified by:

write in interface GatheringByteChannel

Throws:

IOException

write

public long write(ByteBuffer[] srcs)
           throws IOException

Specified by:

write in interface GatheringByteChannel

Throws:

IOException

position

public long position()
              throws IOException

Specified by:

position in interface SeekableByteChannel

Throws:

IOException

position

public CleanableFileChannel position(long newPosition)
                              throws IOException

Specified by:

position in interface SeekableByteChannel

Throws:

IOException

size

public long size()
          throws IOException

Specified by:

size in interface SeekableByteChannel

Throws:

IOException

truncate

public CleanableFileChannel truncate(long size)
                              throws IOException

Specified by:

truncate in interface SeekableByteChannel

Throws:

IOException

force

public void force(boolean metaData)
           throws IOException

Throws:

IOException

transferTo

public long transferTo(long position,
 long count,
 WritableByteChannel target)
                throws IOException

Throws:

IOException

transferFrom

public long transferFrom(ReadableByteChannel src,
 long position,
 long count)
                  throws IOException

Throws:

IOException

read

public int read(ByteBuffer dst,
 long position)
         throws IOException

Throws:

IOException

write

public int write(ByteBuffer src,
 long position)
          throws IOException

Throws:

IOException

map

public MappedByteBuffer map(FileChannel.MapMode mode,
 long position,
 long size)
                     throws IOException

Throws:

IOException

lock

public FileLock lock(long position,
 long size,
 boolean shared)
              throws IOException

Throws:

IOException

tryLock

public FileLock tryLock(long position,
 long size,
 boolean shared)
                 throws IOException

Throws:

IOException

isOpen

public boolean isOpen()

Specified by:

isOpen in interface Channel

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Channel

Specified by:

close in interface Closeable