oracle.jbo.server
Class DBTransactionImpl2

java.lang.Object
  oracle.jbo.server.DBTransactionImpl
      oracle.jbo.server.DBTransactionImpl2

All Implemented Interfaces:

PCollManagerHelper, JboTransAttrValidationManager, JboTransValidationManager, DBTransaction, ValidationManager, Transaction

public class DBTransactionImpl2
extends DBTransactionImpl

Implementation of DBTransaction interface for representing both "connected" and "not connected" state. In pre 9.0.3 versions the disconnected and connected state implementation was provided by NullDBTransactionImpl and DBTransactionImpl respectivey. DBTransactionImpl instance was created only when clients initiated the acquisition of a jdbc connection by calling the one of Transaction.connect() or Transaction.connectToDataSource() methods.

Beginning from 9.0.3 Creation of root application module results in creation DBTransactionImpl2 instance in disconnected state. Later when clients request acquistion of jdbc connection this instance migrates from disconnected to connected state.

Since:

JDeveloper 9.0.3

See Also:

oracle.jbo.server.DatabaseTransactionFactory

Field Summary

static java.lang.Class

CLASS_INSTANCE

Fields inherited from class oracle.jbo.server.DBTransactionImpl

MAX_CURSORS_UNINITIALIZED, mConnectionMetaData, mDMLOperationTimeOut, mLongRunningDMLOperationHandles, POST_ABORT_ON_FIRST_EXCEPTION, POST_ALL_NO_RESET_ON_EXCEPTION, POST_ALL_RESET_ON_EXCEPTION

Fields inherited from interface oracle.jbo.server.DBTransaction

DEFAULT

Fields inherited from interface oracle.jbo.Transaction

DML_OPERATION_TIMEOUT_WAIT_FOREVER, LOCK_NONE, LOCK_OPTIMISTIC, LOCK_OPTUPDATE, LOCK_PESSIMISTIC

Constructor Summary

DBTransactionImpl2()

Method Summary

CallableStatement	createCallableStatement(java.lang.String str, int noRowsPrefetch) Implementation of createCallableStatement method.
PreparedStatement	createPreparedStatement(java.lang.String str, int noRowsPrefetch) Implementation of createPreparedStatement method.
Statement	createStatement(int noRowsPrefetch) Implementation of createStatement method.
void	rollback() Discards all modifications made in this transaction.

Methods inherited from class oracle.jbo.server.DBTransactionImpl

addLongRunningDMLOperationHandle, addToValidationListeners, addTransactionListener, addTransactionListenerNoCheck, addTransactionPostListener, addTransactionPostListenerNoCheck, addTransactionStateListener, addViewClearCacheListener, applyChangeSet, cancelDMLOperations, checkConnected, clearEntityCache, closeTransaction, commit, commitAndSaveChangeSet, connect, connect, connect, connect, connectToDataSource, connectToDataSource, connectToDataSource, connectToDataSource, createPreparedStatement, createRef, createStatement, createViewObjectFromQueryClauses, disconnect, disconnect, doCommit, doRollback, dumpQueryResult, executeCommand, findEntityCache, getBatchPostExceptionThreshold, getConnectionMetadata, getDMLOperationTimeOut, getEntityCache, getEntityCache, getJdbcConnection, getLockingMode, getPersistManagerConnection, getPostChangesFlag, getPostThreshold, getRootApplicationModule, getSession, getSQLBuilder, getSyncLock, getTransactionHandler, getTransactionState, getTransAttrValidationList, getTransAttrValidationManager, getTransAttrValidations, getTransValidationList, getTransValidationManager, getTransValidations, getTxnApplicationModuleImpl, getValidationThreshold, hasRollbackSavePoint, isBundledExceptionMode, isClearCacheOnCommit, isClearCacheOnRollback, isConnected, isConnected, isDirty, isForceDeferValidation, isTrackNewAndModifiedRowsOnly, lookupEntityCache, postChanges, postChanges, putTransAttrValEntry, putTransValEntry, reconnect, reconnect, removeChangeSet, removeLongRunningDMLOperationHandle, removeTransactionListener, removeTransactionPostListener, removeTransactionStateListener, removeViewClearCacheListener, setBatchModeForEntity, setBundledExceptionMode, setClearCacheOnCommit, setClearCacheOnRollback, setDMLOperationTimeOut, setForceDeferValidation, setLockingMode, setTransactionHandler, setValidationThreshold, validate

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

CLASS_INSTANCE

public static final java.lang.Class CLASS_INSTANCE

Constructor Detail

DBTransactionImpl2

public DBTransactionImpl2()

Method Detail

createStatement

public Statement createStatement(int noRowsPrefetch)

Implementation of createStatement method.

Specified by:

createStatement in interface DBTransaction

Overrides:

createStatement in class DBTransactionImpl

Parameters:

noRowsPrefetch - the number of rows to prefetch when executing this statement's query.

Returns:

a JDBC Statement instance.

Throws:

NotConnectedException - if no jdbc connection was acquired

createCallableStatement

public CallableStatement createCallableStatement(java.lang.String str,
                                                 int noRowsPrefetch)

Implementation of createCallableStatement method.

Overrides:

createCallableStatement in class DBTransactionImpl

Throws:

NotConnectedException - if no jdbc connection was acquired

createPreparedStatement

public PreparedStatement createPreparedStatement(java.lang.String str,
                                                 int noRowsPrefetch)

Implementation of createPreparedStatement method.

Specified by:

createPreparedStatement in interface DBTransaction

Overrides:

createPreparedStatement in class DBTransactionImpl

Parameters:

str - the PreparedStatement instance's SQL statement.

noRowsPrefetch - the number of rows to prefetch when executing this statement's query. If this parameter is set to DBTransaction.DEFAULT, then the default value from the jdbc driver is used.

Returns:

a JDBC PreparedStatement instance.

Throws:

NotConnectedException - if no jdbc connection was acquired

rollback

public void rollback()

Description copied from class: DBTransactionImpl

Discards all modifications made in this transaction. This method is called on the Application Module's transaction. For example:

 appMod.getTransaction().rollback();
 

When this method is invoked, beforeRollback events are posted to the listeners, the changes are discarded, afterRollback events are posted, and transient listeners are deleted from the transaction. For both events, non-transient listeners preceed transient listeners.

In the following example, a method named updateAttr has been implemented to update a row of a View Object vo with the value newAttrVal. If updateAttr succeeds (returns true), the code commits the transaction; otherwise, it rolls the transaction back:

 // Assume that appMod has been declared and initialized elsewhere.
 try
 {
   if (updateAttr(vo, newAttrVal))
   {
     // Commit changes to the database, making
     // updated data available to other Application Modules.
     appMod.getTransaction().commit();
     System.out.println("\n Transaction committed. \n");
   }
   else
   {
     appMod.getTransaction().rollback();
     System.out.println("\n Transaction rolled back. \n");
   }
 }
 catch (Exception e)
 {
   e.printStackTrace();
 }
 

Note, if your Application Module is an EJB session bean, a new transaction is started for you automatically after calling rollback. You do not have to explicitly start a new transaction.

Specified by:

rollback in interface Transaction

Overrides:

rollback in class DBTransactionImpl

See Also:

DBTransaction, TransactionListener.afterRollback(TransactionEvent), TransactionListener.beforeRollback(TransactionEvent)