org.corfudb.runtime.view.stream

Class ThreadSafeStreamView

java.lang.Object

org.corfudb.runtime.view.stream.ThreadSafeStreamView

All Implemented Interfaces:

Iterator<ILogData>, IStreamView

public class ThreadSafeStreamView
extends Object
implements IStreamView

A thread-safe implementation of IStreamView. Created by Maithem on 11/30/18.

Nested Class Summary

Nested classes/interfaces inherited from interface org.corfudb.runtime.view.stream.IStreamView

IStreamView.SearchDirection

Constructor Summary

Constructors

Constructor and Description
ThreadSafeStreamView(CorfuRuntime runtime, UUID streamId)
ThreadSafeStreamView(CorfuRuntime runtime, UUID streamId, StreamOptions options)

Method Summary

Modifier and Type	Method and Description
long	append(Object object, Function<TokenResponse,Boolean> acquisitionCallback, Function<TokenResponse,Boolean> deacquisitionCallback) Append an object to the stream, returning the global address it was written at.
ILogData	current() Retrieve the current entry in the stream, which was the entry previously returned by a call to next() or previous().
long	find(long globalAddress, IStreamView.SearchDirection direction) Find the global address of the next entry in this stream, in the direction given.
void	gc(long trimMark) Garbage collect all the trimmed entries on this stream
long	getCurrentGlobalPosition() Get the current position of the pointer in this stream (global address).
UUID	getId() Return the ID of the stream this view is for.
long	getTotalUpdates() Get total number of updates registered to this stream.
boolean	hasNext() Returns whether or not there are potentially more entries in this stream - this function may return true even if there are no entries remaining, as addresses may have been acquired by other clients but not written yet, or the addresses were hole-filled, or just failed.
ILogData	next() Retrieve the next entry from this stream, up to the tail of the stream If there are no entries present, this function will return NULL.
ILogData	nextUpTo(long maxGlobal) Retrieve the next entry from this stream, up to the address given or the tail of the stream.
ILogData	previous() Retrieve the previous entry in the stream.
List<ILogData>	remainingUpTo(long maxGlobal) Retrieve all of the entries from this stream, up to the address given or the tail of the stream.
void	reset() Reset the state of this stream view, causing the next read to start from the beginning of this stream.
void	seek(long globalAddress) Seek to the requested maxGlobal address.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.corfudb.runtime.view.stream.IStreamView

append, remaining, spliterator, spliteratorUpTo, stream, streamUpTo

Methods inherited from interface java.util.Iterator

forEachRemaining, remove

Constructor Detail

ThreadSafeStreamView

public ThreadSafeStreamView(CorfuRuntime runtime,
                            UUID streamId,
                            @Nonnull
                            StreamOptions options)

ThreadSafeStreamView

public ThreadSafeStreamView(CorfuRuntime runtime,
                            UUID streamId)

Method Detail

getId

public UUID getId()

Description copied from interface: IStreamView

Return the ID of the stream this view is for.

Specified by:

getId in interface IStreamView

Returns:

The ID of the stream.

reset

public void reset()

Description copied from interface: IStreamView

Reset the state of this stream view, causing the next read to start from the beginning of this stream.

Specified by:

reset in interface IStreamView

gc

public void gc(long trimMark)

Description copied from interface: IStreamView

Garbage collect all the trimmed entries on this stream

Specified by:

gc in interface IStreamView

Parameters:

trimMark - start of the active log

seek

public void seek(long globalAddress)

Description copied from interface: IStreamView

Seek to the requested maxGlobal address. The next read will begin at the given global address, inclusive.

Specified by:

seek in interface IStreamView

Parameters:

globalAddress - Address to seek to

find

public long find(long globalAddress,
                 IStreamView.SearchDirection direction)

Description copied from interface: IStreamView

Find the global address of the next entry in this stream, in the direction given.

Specified by:

find in interface IStreamView

Parameters:

globalAddress - The global address to start searching from.

direction - The direction to search.

Returns:

The global address of the next entry in the stream, or Address.NOT_FOUND if no entry was found.

append

public long append(Object object,
                   Function<TokenResponse,Boolean> acquisitionCallback,
                   Function<TokenResponse,Boolean> deacquisitionCallback)

Description copied from interface: IStreamView

Append an object to the stream, returning the global address it was written at.

Optionally, provide a method to be called when an address is acquired, and also a method to be called when an address is released (due to an unsuccessful append).

Specified by:

append in interface IStreamView

Parameters:

object - The object to append.

acquisitionCallback - A function to call when an address is acquired. It should return true to continue with the append.

deacquisitionCallback - A function to call when an address is released. It should return true to retry writing.

Returns:

The (global) address the object was written at.

next

public ILogData next()

Description copied from interface: IStreamView

Retrieve the next entry from this stream, up to the tail of the stream If there are no entries present, this function will return NULL. If there are holes present in the log, they will be filled.

Specified by:

next in interface Iterator<ILogData>

Specified by:

next in interface IStreamView

Returns:

The next entry in the stream, or NULL, if no entries are available.

previous

public ILogData previous()

Description copied from interface: IStreamView

Retrieve the previous entry in the stream. If there are no previous entries, NULL will be returned.

Specified by:

previous in interface IStreamView

Returns:

The previous entry in the stream, or NULL, if no entries are available.

current

public ILogData current()

Description copied from interface: IStreamView

Retrieve the current entry in the stream, which was the entry previously returned by a call to next() or previous(). If the stream was never read from, NULL will be returned.

Specified by:

current in interface IStreamView

Returns:

The current entry in the stream.

nextUpTo

public ILogData nextUpTo(long maxGlobal)

Description copied from interface: IStreamView

Retrieve the next entry from this stream, up to the address given or the tail of the stream. If there are no entries present, this function will return NULL. If there are holes present in the log, they will be filled.

Specified by:

nextUpTo in interface IStreamView

Parameters:

maxGlobal - The maximum global address to read up to.

Returns:

The next entry in the stream, or NULL, if no entries are available.

remainingUpTo

public List<ILogData> remainingUpTo(long maxGlobal)

Description copied from interface: IStreamView

Retrieve all of the entries from this stream, up to the address given or the tail of the stream. If there are no entries present, this function will return an empty list. If there are holes present in the log, they will be filled.

Specified by:

remainingUpTo in interface IStreamView

Parameters:

maxGlobal - The maximum global address to read up to.

Returns:

The next entries in the stream, or an empty list, if no entries are available.

hasNext

public boolean hasNext()

Description copied from interface: IStreamView

Returns whether or not there are potentially more entries in this stream - this function may return true even if there are no entries remaining, as addresses may have been acquired by other clients but not written yet, or the addresses were hole-filled, or just failed.

Specified by:

hasNext in interface Iterator<ILogData>

Specified by:

hasNext in interface IStreamView

Returns:

True, if there are potentially more entries in the stream.

getCurrentGlobalPosition

public long getCurrentGlobalPosition()

Description copied from interface: IStreamView

Get the current position of the pointer in this stream (global address).

Specified by:

getCurrentGlobalPosition in interface IStreamView

Returns:

The position of the pointer in this stream (global address), or Address.NON_ADDRESS.

getTotalUpdates

public long getTotalUpdates()

Description copied from interface: IStreamView

Get total number of updates registered to this stream.

Specified by:

getTotalUpdates in interface IStreamView

Returns:

total number of updates belonging to this stream.