Package org.apache.accumulo.core.fate

Interface TStore<T>

All Superinterfaces:

ReadOnlyTStore<T>

All Known Implementing Classes:

AgeOffStore, ZooStore

public interface TStore<T>
extends ReadOnlyTStore<T>

Transaction Store: a place to save transactions A transaction consists of a number of operations. To use, first create a transaction id, and then seed the transaction with an initial operation. An executor service can then execute the transaction's operation, possibly pushing more operations onto the transaction as each step successfully completes. If a step fails, the stack can be unwound, undoing each operation.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.accumulo.core.fate.ReadOnlyTStore

ReadOnlyTStore.TStatus

Method Summary

Modifier and Type	Method	Description
long	create()	Create a new transaction id
void	delete(long tid)	Remove the transaction from the store.
void	pop(long tid)	Remove the last pushed operation from the given transaction.
void	push(long tid, Repo<T> repo)	Update the given transaction with the next operation
void	setStatus(long tid, ReadOnlyTStore.TStatus status)	Update the state of a given transaction
void	setTransactionInfo(long tid, Fate.TxInfo txInfo, Serializable val)	Set transaction-specific information.
Repo<T>	top(long tid)	Get the current operation for the given transaction id.
boolean	tryReserve(long tid)	Attempt to reserve transaction

Methods inherited from interface org.apache.accumulo.core.fate.ReadOnlyTStore

getStack, getStatus, getTransactionInfo, list, reserve, reserve, timeCreated, unreserve, waitForStatusChange

Method Detail

create

long create()

Create a new transaction id

Returns:

a transaction id

top

Repo<T> top(long tid)

Description copied from interface: ReadOnlyTStore

Get the current operation for the given transaction id. Caller must have already reserved tid.

Specified by:

top in interface ReadOnlyTStore<T>

Parameters:

tid - transaction id, previously reserved.

Returns:

a read-only view of the operation

push

void push(long tid,
          Repo<T> repo)
   throws StackOverflowException

Update the given transaction with the next operation

Parameters:

tid - the transaction id

repo - the operation

Throws:

StackOverflowException

pop

void pop(long tid)

Remove the last pushed operation from the given transaction.

setStatus

void setStatus(long tid,
               ReadOnlyTStore.TStatus status)

Update the state of a given transaction

Parameters:

tid - transaction id

status - execution status

setTransactionInfo

void setTransactionInfo(long tid,
                        Fate.TxInfo txInfo,
                        Serializable val)

Set transaction-specific information.

Parameters:

tid - transaction id

txInfo - name of attribute of a transaction to set.

val - transaction data to store

delete

void delete(long tid)

Remove the transaction from the store.

Parameters:

tid - the transaction id

tryReserve

boolean tryReserve(long tid)

Attempt to reserve transaction

Parameters:

tid - transaction id

Returns:

true if reserved by this call, false if already reserved