org.modelsphere.jack.baseDb.db
Class DbTransaction
java.lang.Object
org.modelsphere.jack.baseDb.db.DbTransaction
public class DbTransaction
- extends java.lang.Object
Implements the transaction concept for the Db framework. A transaction starts
with a beginReadTrans()
or a beginWriteTrans()
.
A transactions terminates with a commitTrans()
(successful
completion) or with a a abortTrans()
(unsuccessful completion).
All the accesses to DbObject's values (either read accesses or writer accesses)
must occur within a transaction, otherwise a DbException is thrown.
A transaction is ACID (Atomic, Concurrent, Isolated and Durable). Atomic
means the transaction is either totally committed or totally rolled back.
Concurrent means multi-user access is handled by the transaction framework.
Isolated means all the changes to the DbObject are not visible to other users
until the transaction is committed. Durable means the transaction are
stored in a transaction history, and can be undone or redone.
A transaction contains an ordered collection of all the commands
performed. When the transaction starts, the command list is empty.
An invocation to a setter actually creates a command and add it to the
command list. At the commit time, all the commands are executed. If an
error occurs when executing a command, and the previously executed commands
are rolled back, in order to leave the DbObject instance in the same state it
was when the transaction begun.
Transactions are managed by the Db instance. Transaction commands can
be executed in reverse order (undo operation).
- See Also:
Db.beginReadTrans()
,
Db.beginWriteTrans(String)
,
Db.commitTrans()
,
Db.abortTrans()
,
Db.undo()
,
Db.redo()
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
getName
public final java.lang.String getName()
- Returns:
- The localized transaction name.
setName
public final void setName(java.lang.String name)
- Parameters:
name
- The new localized name. This value is visible to the user.
getDescription
public final java.lang.String getDescription()
setDescription
public final void setDescription(java.lang.String description)
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