Java Transaction API Interview Questions And Answers

Java Transaction API is a standard between the transaction manager and the entities participated in the distributed transaction system. These entities are transaction manager, the application server and transactional applications. JTA allows the applications to perform distributed transactions between one or more systems connected to the network. The database access power is greatly increased by supporting JTA in a JDBC driver.

The resource manager can be viewed as a RDBMS. This component handles the actual database management. The communication channel is the resource adapter which is a JDBC driver. For a specific enterprise database, the resource manager local transaction is performed for a single transaction.

A bean managed transaction is an explicitly bounded for a specific transaction that is handled by a bean. The bean managed transaction is considered , in a situation as container-managed transaction has a limitation. The limitation is , the association with a specific / several transactions is not certain and it is difficult to make coding the bean. In this specific circumstance, the bean managed transaction yields good results.

Declarative transaction demarcation is also known as Container-Managed Transaction. The container demarcates different transactions as per the requirements specified by the application assembler in deployment descriptor. These instructions are called as transaction attributes.

Programmatic Demarcation can also called as Bean-Managed Transaction. The bean code that demarcates using the javax.transaction.UserTransactijon interface.

Demarcation specifies a limit for a bean managed transaction, i.e. once a transaction begins, it ends with either commit or abort the key points of who issues begin and who issues commit or abort is called demarcating transactional boundaries.

Declarative Demarcation
Declarative transaction demarcation is also known as Container-Managed Transaction. The container demarcates different transactions as per the requirements specified by the application assembler in deployment descriptor. These instructions are called as transaction attributes.

Programmatic Demarcation
Programmatic Demarcation can also be called as Bean-Managed Transaction, the bean code that demarcates using the javax.transaction.UserTransaction interface.

The resources are accessed between javax.transaction.UserTransaction.begin() and javax.transaction.UserTransaction.commit(). This access makes the part of the transaction. The resource and resource manager declared in the deployment descriptor.

Required: This is the default transaction attribute that ensures the methods are invoked within Java Transaction API transaction context. Required makes the transactional context used by the bean. If not the new context will be created.

RequiredNew: RequiredNew is used when the required results of the transactions to be committed irrespective of the caller’s transactions.

Mandatory: In the situation when the method absolutely requires an existing transaction.

Supports: Supports attribute when the methods do not change database or update the atomicity without the concern of the update of the transaction.

NotSupported: At the time of enterprise bean access a resource manager with or without the support of the external transaction coordination or not supported by the J2EE product, the NotSupported attribute is used.

Never: When the methods that are not capable of participating in transactions are not accessible by a transactional client, Never is used.

Bean-managed: Bean-managed transactions include any stateful or stateless session beans with a transaction-type set to Bean. The bean specifies the transaction demarcations using the javax.transactin.UserTransaction interface.