org.modelsphere.jack.baseDb.db
Class DbTransaction

java.lang.Object
  extended by 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()

Method Summary
 java.lang.String getDescription()
           
 java.lang.String getName()
           
 void setDescription(java.lang.String description)
           
 void setName(java.lang.String name)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Method Detail

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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