com.faunos.skwish.sys.mgr
Class Store

java.lang.Object
  com.faunos.skwish.SegmentStore
      com.faunos.skwish.sys.mgr.Store

All Implemented Interfaces:

Closeable, Channel

public class Store
extends SegmentStore

The SegmentStore implementation.

Author:

Babak Farhang

Field Summary

protected static ChannelUtil<SegmentStoreException>	channelHelper
static Version	VERSION

Fields inherited from class com.faunos.skwish.SegmentStore

validator

Constructor Summary

	Store(File rootDir) Reads the given root directory and creates a new instance.
protected	Store(File rootDir, boolean create)

Method Summary

void	close() Closes the instance.
Version	getFileVersion()
static Provider	getProvider()
Segment	getReadOnlySegment() Returns the live read-only view of the committed segments.
File	getRootDirectory()
long	getTxnCommitIdGap(long txnId) Returns the transaction commit id gap recorded on commit for the specified transaction, or -1, if the transaction is pending or discarded.
String	getUri() Returns the URI used to load this instance.
boolean	isOpen()
TxnSegment	newTransaction() Returns a new transaction [segment].

Methods inherited from class com.faunos.skwish.SegmentStore

loadInstance, setProvider, writeNewInstance

Methods inherited from class java.lang.Object

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

Field Detail

VERSION

public static final Version VERSION

channelHelper

protected static final ChannelUtil<SegmentStoreException> channelHelper

Constructor Detail

Store

public Store(File rootDir)
      throws IOException

Reads the given root directory and creates a new instance.

Throws:

IOException

Store

protected Store(File rootDir,
                boolean create)
         throws IOException

Throws:

IOException

Method Detail

getProvider

public static Provider getProvider()

getFileVersion

public Version getFileVersion()
                       throws IOException

Throws:

IOException

getRootDirectory

public File getRootDirectory()

getUri

public String getUri()

Description copied from class: SegmentStore

Returns the URI used to load this instance.

Specified by:

getUri in class SegmentStore

getReadOnlySegment

public Segment getReadOnlySegment()
                           throws IOException

Description copied from class: SegmentStore

Returns the live read-only view of the committed segments. Transactions are immediately visible on commit.

Specified by:

getReadOnlySegment in class SegmentStore

Throws:

IOException

isOpen

public boolean isOpen()

newTransaction

public TxnSegment newTransaction()
                          throws IOException

Description copied from class: SegmentStore

Returns a new transaction [segment]. Transactions allow changes to be committed in all-or-nothing fashion. There is no architectural limit on the number of transactions that can be concurrently open (pending). Also, while transactions (TxnSegments) are not individually thread-safe, each transaction may be run concurrently in its own thread.

Specified by:

newTransaction in class SegmentStore

Throws:

IOException

getTxnCommitIdGap

public long getTxnCommitIdGap(long txnId)
                       throws IOException,
                              NotFoundException

Description copied from class: SegmentStore

Returns the transaction commit id gap recorded on commit for the specified transaction, or -1, if the transaction is pending or discarded.

Specified by:

getTxnCommitIdGap in class SegmentStore

Parameters:

txnId - the transaction id (from TxnSegment.getTxnId())

Throws:

NotFoundException - If txnId does not specify a known transaction

IOException

close

public void close()
           throws IOException

Description copied from class: SegmentStore

Closes the instance. All Segments opened by this instance are implicitly closed, and any uncommitted TxnSegments are discarded.

Specified by:

close in interface Closeable

Specified by:

close in interface Channel

Specified by:

close in class SegmentStore

Throws:

IOException