Package org.apache.bookkeeper.client

Class ReadOnlyLedgerHandle

java.lang.Object

org.apache.bookkeeper.client.LedgerHandle

org.apache.bookkeeper.client.ReadOnlyLedgerHandle

All Implemented Interfaces:

AutoCloseable, ForceableHandle, Handle, ReadHandle, WriteHandle, BookkeeperInternalCallbacks.LedgerMetadataListener

class ReadOnlyLedgerHandle
extends LedgerHandle
implements BookkeeperInternalCallbacks.LedgerMetadataListener

Read only ledger handle. This ledger handle allows you to read from a ledger but not to write to it. It overrides all the public write operations from LedgerHandle. It should be returned for BookKeeper#openLedger operations.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) class	ReadOnlyLedgerHandle.MetadataUpdater

Nested classes/interfaces inherited from class org.apache.bookkeeper.client.LedgerHandle

LedgerHandle.LastConfirmedCtx, LedgerHandle.NoopCloseCallback

Field Summary

Fields inherited from class org.apache.bookkeeper.client.LedgerHandle

bookieFailureHistory, bookiesHealthInfo, changingEnsemble, clientCtx, delayedWriteFailedBookies, distributionSchedule, ensembleChangeCounter, executor, explicitLacFlushPolicy, INVALID_ENTRY_ID, INVALID_LEDGER_ID, lacUpdateHitsCounter, lacUpdateMissesCounter, lastAddConfirmed, lastAddPushed, ledgerId, ledgerKey, length, macManager, notSupportBatch, numEnsembleChanges, pendingAddOps, pendingAddsSequenceHead, throttler, timeoutFuture, writeFlags

Constructor Summary

Constructors

Constructor	Description
ReadOnlyLedgerHandle(ClientContext clientCtx, long ledgerId, Versioned<LedgerMetadata> metadata, BookKeeper.DigestType digestType, byte[] password, boolean watchImmediately)

Method Summary

Modifier and Type	Method	Description
long	addEntry(byte[] data)	Add entry synchronously to an open ledger.
long	addEntry(byte[] data, int offset, int length)	Add entry synchronously to an open ledger.
void	asyncAddEntry(byte[] data, int offset, int length, AsyncCallback.AddCallback cb, Object ctx)	Add entry asynchronously to an open ledger, using an offset and range.
void	asyncAddEntry(byte[] data, AsyncCallback.AddCallback cb, Object ctx)	Add entry asynchronously to an open ledger.
void	asyncClose(AsyncCallback.CloseCallback cb, Object ctx)	Asynchronous close, any adds in flight will return errors.
void	asyncReadLastEntry(AsyncCallback.ReadCallback cb, Object ctx)
void	close()	Synchronous close the write handle, any adds in flight will return errors.
(package private) CompletableFuture<Versioned<LedgerMetadata>>	closeRecovered()
(package private) List<BookieId>	getCurrentEnsemble()	Get the current ensemble from the ensemble list.
(package private) void	handleBookieFailure(Map<Integer,BookieId> failedBookies)	For a read only ledger handle, this method will only ever be called during recovery, when we are reading forward from LAC and writing back those entries.
(package private) void	handleUnrecoverableErrorDuringAdd(int rc)
protected void	initializeWriteHandleState()
void	onChanged(long lid, Versioned<LedgerMetadata> newMetadata)	Triggered each time ledger metadata changed.
(package private) void	recover(BookkeeperInternalCallbacks.GenericCallback<Void> finalCb)
(package private) void	recover(BookkeeperInternalCallbacks.GenericCallback<Void> finalCb, BookkeeperInternalCallbacks.ReadEntryListener listener, boolean forceRecovery)	Recover the ledger.
(package private) void	registerLedgerMetadataListener()
String	toString()

Methods inherited from class org.apache.bookkeeper.client.LedgerHandle

addEntry, addEntry, addToLength, appendAsync, asyncAddEntry, asyncAddEntry, asyncAddEntry, asyncAddEntry, asyncAddEntry, asyncBatchReadEntries, asyncBatchReadEntriesInternal, asyncBatchReadUnconfirmedEntries, asyncCloseInternal, asyncReadEntries, asyncReadEntriesInternal, asyncReadExplicitLastConfirmed, asyncReadLastConfirmed, asyncReadLastConfirmedAndEntry, asyncReadUnconfirmedEntries, asyncRecoveryAddEntry, asyncTryReadLastConfirmed, batchReadAsync, batchReadEntries, batchReadUnconfirmedEntries, closeAsync, doAsyncAddEntry, doAsyncCloseInternal, drainPendingAddsAndAdjustLength, ensembleChangeLoop, errorOutPendingAdds, errorOutPendingAdds, executeOrdered, force, getBookiesHealthInfo, getCtime, getCustomMetadata, getDigestManager, getDistributionSchedule, getId, getLastAddConfirmed, getLastAddPushed, getLedgerKey, getLedgerMetadata, getLength, getNumBookies, getNumFragments, getPendingAddOps, getVersionedLedgerMetadata, getWriteFlags, getWriteSetForReadOperation, hasDelayedWriteFailedBookies, isClosed, isHandleWritable, maybeHandleDelayedWriteBookieFailure, notifyWriteFailed, readAsync, readEntries, readEntriesInternalAsync, readExplicitLastConfirmed, readLastAddConfirmedAndEntryAsync, readLastAddConfirmedAsync, readLastConfirmed, readLastEntry, readUnconfirmedAsync, readUnconfirmedEntries, recordReadErrorOnBookie, registerOperationFailureOnBookie, sendAddSuccessCallbacks, setLastAddConfirmed, setLedgerMetadata, tryReadLastAddConfirmedAsync, tryReadLastConfirmed, unsetSuccessAndSendWriteRequest, updateLastConfirmed, waitForWritable

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.bookkeeper.client.api.ReadHandle

batchRead, read, readLastAddConfirmed, readLastAddConfirmedAndEntry, readUnconfirmed, tryReadLastAddConfirmed

Methods inherited from interface org.apache.bookkeeper.client.api.WriteHandle

append, append, append, append, appendAsync, appendAsync, appendAsync

Constructor Details

ReadOnlyLedgerHandle

ReadOnlyLedgerHandle(ClientContext clientCtx,
 long ledgerId,
 Versioned<LedgerMetadata> metadata,
 BookKeeper.DigestType digestType,
 byte[] password,
 boolean watchImmediately)
              throws GeneralSecurityException,
NumberFormatException

Throws:

GeneralSecurityException

NumberFormatException

Method Details

registerLedgerMetadataListener

void registerLedgerMetadataListener()

close

public void close()
           throws InterruptedException,
BKException

Description copied from class: LedgerHandle

Synchronous close the write handle, any adds in flight will return errors.

Closing a ledger will ensure that all clients agree on what the last entry of the ledger is. Once the ledger has been closed, all reads from the ledger will return the same set of entries.

The close operation can error if it finds conflicting metadata when it tries to write to the metadata store. On close, the metadata state is set to closed and lastEntry and length of the ledger are fixed in the metadata. A conflict occurs if the metadata in the metadata store has a different value for the lastEntry or length. If another process has updated the metadata, setting it to closed, but have fixed the lastEntry and length to the same values as this process is trying to write, the operation completes successfully.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Handle

Specified by:

close in interface WriteHandle

Overrides:

close in class LedgerHandle

Throws:

InterruptedException

BKException

See Also:

• Handle.closeAsync()

asyncClose

public void asyncClose(AsyncCallback.CloseCallback cb,
 Object ctx)

Description copied from class: LedgerHandle

Asynchronous close, any adds in flight will return errors.

Closing a ledger will ensure that all clients agree on what the last entry of the ledger is. This ensures that, once the ledger has been closed, all reads from the ledger will return the same set of entries.

Overrides:

asyncClose in class LedgerHandle

Parameters:

cb - callback implementation

ctx - control object

addEntry

public long addEntry(byte[] data)
              throws InterruptedException,
BKException

Description copied from class: LedgerHandle

Add entry synchronously to an open ledger.

Overrides:

addEntry in class LedgerHandle

Parameters:

data - array of bytes to be written to the ledger do not reuse the buffer, bk-client will release it appropriately

Returns:

the entryId of the new inserted entry

Throws:

InterruptedException

BKException

addEntry

public long addEntry(byte[] data,
 int offset,
 int length)
              throws InterruptedException,
BKException

Description copied from class: LedgerHandle

Add entry synchronously to an open ledger.

Overrides:

addEntry in class LedgerHandle

Parameters:

data - array of bytes to be written to the ledger do not reuse the buffer, bk-client will release it appropriately

offset - offset from which to take bytes from data

length - number of bytes to take from data

Returns:

the entryId of the new inserted entry

Throws:

InterruptedException

BKException

asyncAddEntry

public void asyncAddEntry(byte[] data,
 AsyncCallback.AddCallback cb,
 Object ctx)

Description copied from class: LedgerHandle

Add entry asynchronously to an open ledger.

Overrides:

asyncAddEntry in class LedgerHandle

Parameters:

data - array of bytes to be written do not reuse the buffer, bk-client will release it appropriately

cb - object implementing callbackinterface

ctx - some control object

asyncAddEntry

public void asyncAddEntry(byte[] data,
 int offset,
 int length,
 AsyncCallback.AddCallback cb,
 Object ctx)

Description copied from class: LedgerHandle

Add entry asynchronously to an open ledger, using an offset and range.

Overrides:

asyncAddEntry in class LedgerHandle

Parameters:

data - array of bytes to be written do not reuse the buffer, bk-client will release it appropriately

offset - offset from which to take bytes from data

length - number of bytes to take from data

cb - object implementing callbackinterface

ctx - some control object

onChanged

public void onChanged(long lid,
 Versioned<LedgerMetadata> newMetadata)

Description copied from interface: BookkeeperInternalCallbacks.LedgerMetadataListener

Triggered each time ledger metadata changed.

Specified by:

onChanged in interface BookkeeperInternalCallbacks.LedgerMetadataListener

Parameters:

lid - ledger id.

newMetadata - new ledger metadata.

toString

public String toString()

Overrides:

toString in class Object

initializeWriteHandleState

protected void initializeWriteHandleState()

Overrides:

initializeWriteHandleState in class LedgerHandle

asyncReadLastEntry

public void asyncReadLastEntry(AsyncCallback.ReadCallback cb,
 Object ctx)

Overrides:

asyncReadLastEntry in class LedgerHandle

handleBookieFailure

void handleBookieFailure(Map<Integer,BookieId> failedBookies)

For a read only ledger handle, this method will only ever be called during recovery, when we are reading forward from LAC and writing back those entries. As such, unlike with LedgerHandle, we do not want to persist changes to the metadata as they occur, but rather, we want to defer the persistence until recovery has completed, and do it all on the close.

Overrides:

handleBookieFailure in class LedgerHandle

handleUnrecoverableErrorDuringAdd

void handleUnrecoverableErrorDuringAdd(int rc)

Overrides:

handleUnrecoverableErrorDuringAdd in class LedgerHandle

recover

void recover(BookkeeperInternalCallbacks.GenericCallback<Void> finalCb)

recover

void recover(BookkeeperInternalCallbacks.GenericCallback<Void> finalCb,
 BookkeeperInternalCallbacks.ReadEntryListener listener,
 boolean forceRecovery)

Recover the ledger.

Parameters:

finalCb - callback after recovery is done.

listener - read entry listener on recovery reads.

forceRecovery - force the recovery procedure even the ledger metadata shows the ledger is closed.

closeRecovered

CompletableFuture<Versioned<LedgerMetadata>> closeRecovered()

getCurrentEnsemble

List<BookieId> getCurrentEnsemble()

Description copied from class: LedgerHandle

Get the current ensemble from the ensemble list. The current ensemble is the last ensemble in the list. The ledger handle uses this ensemble when triggering operations which work on the end of the ledger, such as adding new entries or reading the last add confirmed.

This method is also used by ReadOnlyLedgerHandle during recovery, and when tailing a ledger.

Generally, this method should only be called by LedgerHandle and not by the operations themselves, to avoid adding more dependencies between the classes. There are too many already.

Overrides:

getCurrentEnsemble in class LedgerHandle