com.google.common.io
Class FileBackedOutputStream

java.lang.Object
  java.io.OutputStream
      com.google.common.io.FileBackedOutputStream

All Implemented Interfaces:

Closeable, Flushable

public final class FileBackedOutputStream
extends OutputStream

An OutputStream that starts buffering to a byte array, but switches to file buffering once the data reaches a configurable size.

This class is thread-safe.

Since:

2009.09.15 tentative

Author:

Chris Nokleberg

Constructor Summary

FileBackedOutputStream(int fileThreshold)
Creates a new instance that uses the given file threshold.

FileBackedOutputStream(int fileThreshold, boolean resetOnFinalize)
Creates a new instance that uses the given file threshold, and optionally resets the data when the InputSupplier returned by getSupplier() is finalized.

Method Summary

void	close()
void	flush()
InputSupplier<InputStream>	getSupplier() Returns a supplier that may be used to retrieve the data buffered by this stream.
void	reset() Calls close() if not already closed, and then resets this object back to its initial state, for reuse.
void	write(byte[] b)
void	write(byte[] b, int off, int len)
void	write(int b)

Methods inherited from class java.lang.Object

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

Constructor Detail

FileBackedOutputStream

public FileBackedOutputStream(int fileThreshold)

Creates a new instance that uses the given file threshold. Equivalent to ThresholdOutputStream(fileThreshold, false).

Parameters:

fileThreshold - the number of bytes before the stream should switch to buffering to a file

FileBackedOutputStream

public FileBackedOutputStream(int fileThreshold,
                              boolean resetOnFinalize)

Creates a new instance that uses the given file threshold, and optionally resets the data when the InputSupplier returned by getSupplier() is finalized.

Parameters:

fileThreshold - the number of bytes before the stream should switch to buffering to a file

resetOnFinalize - if true, the reset() method will be called when the InputSupplier returned by getSupplier() is finalized

Method Detail

getSupplier

public InputSupplier<InputStream> getSupplier()

Returns a supplier that may be used to retrieve the data buffered by this stream.

reset

public void reset()
           throws IOException

Calls close() if not already closed, and then resets this object back to its initial state, for reuse. If data was buffered to a file, it will be deleted.

Throws:

IOException - if an I/O error occurred while deleting the file buffer

write

public void write(int b)
           throws IOException

Specified by:

write in class OutputStream

Throws:

IOException

write

public void write(byte[] b)
           throws IOException

Overrides:

write in class OutputStream

Throws:

IOException

write

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

Overrides:

write in class OutputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException