Package com.mimecast.robin.storage

Class MessageBufferOutputStream

java.lang.Object

java.io.OutputStream

com.mimecast.robin.storage.MessageBufferOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

public class MessageBufferOutputStream
extends OutputStream

Buffers message receipt in memory and spills to disk after a configured threshold.

Field Summary

Fields

Modifier and Type	Field	Description
private OutputStream	activeStream
private boolean	closed
private ByteArrayOutputStream	memoryStream
private long	size
private final Path	spillFile
private final long	thresholdBytes

Constructor Summary

Constructors

Constructor	Description
MessageBufferOutputStream(long thresholdBytes, Path spillFile)	Constructs a new buffered output stream.

Method Summary

Modifier and Type	Method	Description
void	close()
private void	ensureOpen()
void	flush()
void	forceSpillToFile()	Forces the buffer to spill to file regardless of threshold.
boolean	isSpilledToFile()	Checks if the stream spilled to a file.
long	size()	Gets the buffered size.
private void	spillIfNeeded(int nextWriteBytes)
MessageSource	toMessageSource()	Converts the current buffer into a canonical message source.
void	write(byte[] b, int off, int len)
void	write(int b)

Methods inherited from class java.io.OutputStream

nullOutputStream, write

Methods inherited from class java.lang.Object

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

Field Details

thresholdBytes

private final long thresholdBytes

spillFile

private final Path spillFile

memoryStream

private ByteArrayOutputStream memoryStream

activeStream

private OutputStream activeStream

size

private long size

closed

private boolean closed

Constructor Details

MessageBufferOutputStream

public MessageBufferOutputStream(long thresholdBytes,
 Path spillFile)

Constructs a new buffered output stream.

Parameters:

thresholdBytes - Spill threshold.

spillFile - Spill target file.

Method Details

write

public void write(int b)
           throws IOException

Specified by:

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

flush

public void flush()
           throws IOException

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException

size

public long size()

Gets the buffered size.

Returns:

Size in bytes.

toMessageSource

public MessageSource toMessageSource()

Converts the current buffer into a canonical message source.

For file-backed messages, returns a RefCountedFileMessageSource to support safe concurrent access with automatic cleanup.

Returns:

MessageSource instance.

isSpilledToFile

public boolean isSpilledToFile()

Checks if the stream spilled to a file.

Returns:

Boolean.

forceSpillToFile

public void forceSpillToFile()
                      throws IOException

Forces the buffer to spill to file regardless of threshold.

Useful for bot processing where file-based access is required for thread-safe concurrent access to the message content.

Throws:

IOException - If an I/O error occurs.

spillIfNeeded

private void spillIfNeeded(int nextWriteBytes)
                    throws IOException

Throws:

IOException

ensureOpen

private void ensureOpen()
                 throws IOException

Throws:

IOException