com.netflix.genie.web.util

Class StreamBuffer

java.lang.Object

com.netflix.genie.web.util.StreamBuffer

@ThreadSafe
public class StreamBuffer
extends java.lang.Object

A temporary in-memory structure to hold in-transit data. Provides an InputStream for reading, reading blocks until data becomes available or the buffer is closed.

To avoid in-memory data growing excessively, this buffer stores a single "chunk" at the time. Only after a chunk is consumed, a new one can be appended.

To support range requests in a memory-efficient way, StreamBufferInputStream also allows skipping the first skipOffset - 1 bytes without allocating memory (or worse: downloading the actual bytes only to have them thrown away to get to the actual range)

Since:

4.0.0

Constructor Summary

Constructors

Constructor and Description
StreamBuffer(long skipOffset) Constructor.

Method Summary

Modifier and Type	Method and Description
void	closeForCompleted() Close this buffer because all expected data has been written Reading will return the end of stream marker after all data has been consumed.
void	closeForError(java.lang.Throwable t) Close this buffer before all data is written due to an error.
java.io.InputStream	getInputStream() Obtain the input stream to read this data.
boolean	tryWrite(com.google.protobuf.ByteString data) Try to append a chunk of data for consumption.
void	write(com.google.protobuf.ByteString data) Append a chunk of data for consumption.

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamBuffer

public StreamBuffer(long skipOffset)

Constructor.

Parameters:

skipOffset - index of the first actual byte to return (

Method Detail

closeForError

public void closeForError(java.lang.Throwable t)

Close this buffer before all data is written due to an error. Reading will return the end of stream marker after the current chunk (if any) has been consumed.

Parameters:

t - the cause for the buffer to be closed.

closeForCompleted

public void closeForCompleted()

Close this buffer because all expected data has been written Reading will return the end of stream marker after all data has been consumed.

write

public void write(com.google.protobuf.ByteString data)

Append a chunk of data for consumption. This call may block and not return until some data is read/consumed.

Parameters:

data - the data to write into the buffer

Throws:

java.lang.IllegalStateException - if writing is attempted after the buffer has been closed

tryWrite

public boolean tryWrite(com.google.protobuf.ByteString data)

Try to append a chunk of data for consumption. If the previous buffer is still not drained, then does not block and returns false.

Parameters:

data - the data to write into the buffer

Returns:

true if the data was added to the buffer, false otherwise

Throws:

java.lang.IllegalStateException - if writing is attempted after the buffer has been closed

getInputStream

public java.io.InputStream getInputStream()

Obtain the input stream to read this data.

Returns:

the input stream

Throws:

java.lang.IllegalStateException - if invoked multiple times