alluxio

Class StreamCache

java.lang.Object

alluxio.StreamCache

@ThreadSafe
public final class StreamCache
extends Object

Cache for storing file input and output streams. When a stream is added to the cache, the cache returns a unique ID that can be used for future lookups of the stream. The streams are automatically closed when their cache entry is invalidated or after being inactive for an extended period of time.

Constructor Summary

Constructors

Constructor and Description
StreamCache(long timeoutMs) Creates a new instance of StreamCache.

Method Summary

Modifier and Type	Method and Description
FileInStream	getInStream(Integer key)
FileOutStream	getOutStream(Integer key)
Closeable	invalidate(Integer key)
Integer	put(FileInStream is)
Integer	put(FileOutStream os)
long	size()

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamCache

public StreamCache(long timeoutMs)

Creates a new instance of StreamCache.

Parameters:

timeoutMs - the timeout (in milliseconds) for the stream cache eviction

Method Detail

getInStream

public FileInStream getInStream(Integer key)

Parameters:

key - the key to get the stream for

Returns:

the stream or null if the cache contains no stream for the given key

getOutStream

public FileOutStream getOutStream(Integer key)

Parameters:

key - the key to get the stream for

Returns:

the stream or null if the cache contains no stream for the given key

put

public Integer put(FileInStream is)

Parameters:

is - the stream to cache

Returns:

the key for looking up the stream

put

public Integer put(FileOutStream os)

Parameters:

os - the stream to cache

Returns:

the key for looking up the stream

invalidate

@Nullable
public Closeable invalidate(Integer key)

Parameters:

key - the key for the stream to invalidate

Returns:

the invalidated stream or null if the cache contains no stream for the given key

size

public long size()

Returns:

total size of the cache for both input streams and output streams