面接対策、オンラインテスト、チュートリアル、ライブ練習のための学習プラットフォーム

集中型学習パス、模擬テスト、面接向けコンテンツでスキルを伸ばしましょう。

WithoutBook は、分野別の面接質問、オンライン練習テスト、チュートリアル、比較ガイドをひとつのレスポンシブな学習空間にまとめています。

ライブラリを検索

面接準備

質問する

模擬試験

ホームページに設定

このページをブックマーク

EJB 面接の質問と回答

Question: What are the different types of EJB?

Answer:

Mainly three types of EJB:

Entity Bean
Session Bean
Message Driven Bean(MDB)

Types of EJB:
(1) Entity Bean: It represents an entity which is mapped with database or we can say it makes OR object Relational mapping with Database. Entity bean typically represent table in RDBMS and each instance represent row in the table.
Two types of entity bean:

CMP Entity bean: Container managed entity bean its responsibility of container to manage the bean persistence behavior.
BMP Entity bean: Programmer manage the bean persistence behavior.

(2) Session bean: Session bean is responsible for developing business logic it makes the client server relationship so session beans exist till there is a session exist between client and server, it doesn't contain persistent business concept.
Types of session bean:

Stateless session bean: When there is not need to maintain state of a particular client stateless session bean is used .They alive for short period of time. For example if we are validating the credit card we can use stateless session bean.
Stateful session bean: Stateful session bean maintain the conversational state of client over the series of method call before the bean instance goes to passive state conversational state is saved to persistence area like Hard disk and again when same client send a request and bean instance come into the active state it will come out from hard disk to main memory. For Example when we do online banking transaction ,online reservation we use stateful session bean.

(3) Message Driven Beans: These beans are work as a listener for messaging services like JMS.

復習用に保存

この項目をブックマークに追加したり、難しい内容としてマークしたり、復習セットに入れたりできます。

マイ学習ライブラリを開く

役に立ちましたか？はいいいえ

ユーザー評価で最も役立つ内容: