EAServer can automatically retry transactions that are rolled back—method calls back to the last transaction boundary are retried by the stub code. This feature is useful for For EJB CMP entity beans and entity components that use automatic persistence and optimistic concurrency control.
Auto-retry must be enabled for the component that initiates the transaction, which is typically a session bean in EJB applications. Auto-retry works only for intercomponent calls, not for direct invocations of entity beans from the Web tier or base clients.
Auto-retry can be configured in component and server properties as follows:
In component properties, use the Advanced tab to set the property com.sybase.jaguar.component.tx_retry. A value of true enables auto-retry. A value of false disables auto-retry. If this property is not set, the value of the server property com.sybase.jaguar.server.tx_retry is used. If neither the component property or server property is set, the default is false.
In server properties, use the Advanced tab to set the property com.sybase.jaguar.server.tx_retry. The default of false disables auto-retry for all components for which auto-retry is not explicitly enabled. Specify true to enable auto-retry for components for which auto-retry is not explicitly set to false.
Auto-retry is not appropriate for all applications. For example, an end user may want to cancel a purchase if the item price has risen. If auto-retry is disabled, clients must be coded to retry or abort transactions that fail because of stale data. The exception thrown is CORBA::TRANSIENT (for EJB clients, this exception is the root cause of the java.rmi.RemoteException thrown by the EJB stub).
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