net.jini.core.transaction.server
Interface TransactionParticipant
- public abstract interface TransactionParticipant
- extends java.rmi.Remote, TransactionConstants
The interface used for participants of the two-phase commit protocol.
The methods on this interface are called by the transaction manager.
Any class that wants to have operations wrapped in a transaction
needs to support this interface. In conjunction with the
TransactionManager
interface, this interface allows a
two-phase commit protocol to be used between objects in a distributed
system.
- See Also:
TransactionManager
,
NestableTransactionManager
,
ServerTransaction
Method Summary |
void |
abort(TransactionManager mgr,
long id)
Requests that the participant roll back any changes for the specified
transaction and unlock any resources locked by the transaction. |
void |
commit(TransactionManager mgr,
long id)
Requests that the participant make all of its PREPARED
changes for the specified transaction visible outside of the
transaction and unlock any resources locked by the transaction. |
int |
prepare(TransactionManager mgr,
long id)
Requests that the participant prepare itself to commit the transaction,
and to vote on the outcome of the transaction. |
int |
prepareAndCommit(TransactionManager mgr,
long id)
A combination of prepare and commit , which
can be used by the manager when there is just one participant left to
prepare and all other participants (if any) have responded with
NOTCHANGED . |
prepare
public int prepare(TransactionManager mgr,
long id)
throws UnknownTransactionException,
java.rmi.RemoteException
- Requests that the participant prepare itself to commit the transaction,
and to vote on the outcome of the transaction. The participant responds
with either
PREPARED
, indicating that it is prepared;
ABORT
, indicating that it will abort, or
NOTCHANGED
, indicating that it did not have any state
changed by the transaction (i.e., it was read-only). If the response
is PREPARED
, the participant must wait until it receives
a commit or abort call from the transaction manager; it may query the
transaction manager if needed as to the state of the transaction. If
the response is ABORT
, the participant should roll its
state back to undo any changes that occurred due to operations
performed under the transaction; it can then discard any information
about the transaction. If the response is NOTCHANGED
, the
participant can immediately discard any knowledge of the transaction.
- Parameters:
mgr
- the manager of the transactionid
- the transaction id
commit
public void commit(TransactionManager mgr,
long id)
throws UnknownTransactionException,
java.rmi.RemoteException
- Requests that the participant make all of its
PREPARED
changes for the specified transaction visible outside of the
transaction and unlock any resources locked by the transaction.
All state associated with the transaction can then be discarded
by the participant.
- Parameters:
mgr
- the manager of the transactionid
- the transaction id
abort
public void abort(TransactionManager mgr,
long id)
throws UnknownTransactionException,
java.rmi.RemoteException
- Requests that the participant roll back any changes for the specified
transaction and unlock any resources locked by the transaction.
All state associated with the transaction can then be discarded
by the participant.
- Parameters:
mgr
- the manager of the transactionid
- the transaction id
prepareAndCommit
public int prepareAndCommit(TransactionManager mgr,
long id)
throws UnknownTransactionException,
java.rmi.RemoteException
- A combination of
prepare
and commit
, which
can be used by the manager when there is just one participant left to
prepare and all other participants (if any) have responded with
NOTCHANGED
. The participant's implementation of this
method must be equivalent to:
public int prepareAndCommit(TransactionManager mgr, long id)
throws UnknownTransactionException, RemoteException
{
int result = prepare(mgr, id);
if (result == PREPARED) {
commit(mgr, id);
result = COMMITTED;
}
return result;
}
- Parameters:
mgr
- the manager of the transactionid
- the transaction id- See Also:
prepare(net.jini.core.transaction.server.TransactionManager, long)
,
commit(net.jini.core.transaction.server.TransactionManager, long)
Copyright © 1999 Sun Microsystems, Inc. All rights reserved