Package org.aksw.commons.txn.api

Interface TxnMgr

All Known Implementing Classes:

TxnMgrImpl

public interface TxnMgr

Method Summary

Modifier and Type	Method	Description
void	deleteResources()	Method mainly (or rather only) for testing: Clears all locks and transactions regardless of any concurrent access.
TemporalAmount	getHeartbeatDuration()	The time interval between two heartbeats for when transaction metadata in the backend (e.g. a file in the filesystem) is updated to indicate that a transaction's process is still running.
LockStore<String[],String>	getLockStore()
ResourceRepository<String>	getResRepo()
Path	getRootPath()
Txn	getTxn(String txnId)	Get an accessor to an existing transaction
String	getTxnMgrId()
default Txn	newTxn(boolean useJournal, boolean isWrite)
Txn	newTxn(String id, boolean useJournal, boolean isWrite)	Create a new transaction.
Stream<Txn>	streamTxns()	Stream all existing transactions

Method Details

getTxnMgrId

String getTxnMgrId()

getLockStore

LockStore<String[],String> getLockStore()

getResRepo

ResourceRepository<String> getResRepo()

getRootPath

Path getRootPath()

newTxn

Txn newTxn(String id,
 boolean useJournal,
 boolean isWrite)
    throws IOException

Create a new transaction. If the id is null then an id will be allocated. If a txn with the given id already exists an exception in raised.

Throws:

IOException

newTxn

default Txn newTxn(boolean useJournal,
 boolean isWrite)
            throws IOException

Throws:

IOException

getTxn

Txn getTxn(String txnId)

Get an accessor to an existing transaction

streamTxns

Stream<Txn> streamTxns()
                throws IOException

Stream all existing transactions

Throws:

IOException

deleteResources

void deleteResources()
              throws IOException

Method mainly (or rather only) for testing: Clears all locks and transactions regardless of any concurrent access. Resets the txn manager's state to a clean slate.

Throws:

IOException

getHeartbeatDuration

TemporalAmount getHeartbeatDuration()

The time interval between two heartbeats for when transaction metadata in the backend (e.g. a file in the filesystem) is updated to indicate that a transaction's process is still running. Conversely, exceeding the heartbeat duration (with a little margin) indicates that the process managing a transaction must have stopped or is terminated and the transaction can be rolled back.