{"id":66324,"date":"2021-07-18T11:24:59","date_gmt":"2021-07-18T15:24:59","guid":{"rendered":"http:\/\/bangla.salearningschool.com\/recent-posts\/ejb-overview-ejb-in-a-nutshell-java-short-notes\/"},"modified":"2021-07-18T11:24:59","modified_gmt":"2021-07-18T15:24:59","slug":"ejb-overview-ejb-in-a-nutshell-java-short-notes","status":"publish","type":"post","link":"http:\/\/bangla.sitestree.com\/?p=66324","title":{"rendered":"EJB Overview: EJB in a nutshell #Java Short Notes"},"content":{"rendered":"<ul>\n<li> Objects provide encapsulation\/re-usability at the class level.   <\/li>\n<li> A component can be comprised of multiple objects   <\/li>\n<li> Component = logical groups of classes = distributed objects = business objects  <\/li>\n<li> A component can be developed to address a specific enterprise applications.   <\/li>\n<li> Hence, components can provide significant encapsulation\/re-usability in the partitioned enterprise problems.  <\/li>\n<li> Component model = components + their environments + contracts for interaction  <\/li>\n<li> EJB is a server side component model. Used to create application server side components  <\/li>\n<li> Most sophisticated application server = CTM = Transaction Processing Monitors + Object Request Brokers = J2EE Servers  <\/li>\n<li> EJB components: entity, session, message-driven  <\/li>\n<li> Entity beans = real world objects = business objects = data objects = customers = products = may be contained as records in the database = persistent <\/li>\n<li> Multiple clients can access entity beans concurrently <\/li>\n<li>  Session beans = processes + tasks. Example: the act of reserving a ticket = to control work flow = to handle a series of tasks carried out by the entity beans = can also access\/(help to access) data = do not represent data = transient = after the task is done &#8211; no need to maintain states = do not need to support concurrent access<\/li>\n<li> Message-driven beans = stateless beans = no component interface = respond to client requests = clients place requests through JMS = support concurrent client access = can be used to perform tasks and manage interactions among beans = asynchronous = request and response two separate processes, RMI = synchronous<\/li>\n<li><\/li>\n<\/ul>\n<p> From: http:\/\/sitestree.com\/?p=4958<br \/> Categories:Java Short Notes<br \/>Tags:<br \/> Post Data:2012-11-26 13:23:36<\/p>\n<p>\t\tShop Online: <a href='https:\/\/www.ShopForSoul.com\/' target='new' rel=\"noopener\">https:\/\/www.ShopForSoul.com\/<\/a><br \/>\n\t\t(Big Data, Cloud, Security, Machine Learning): Courses: <a href='http:\/\/Training.SitesTree.com' target='new' rel=\"noopener\"> http:\/\/Training.SitesTree.com<\/a><br \/>\n\t\tIn Bengali: <a href='http:\/\/Bangla.SaLearningSchool.com' target='new' rel=\"noopener\">http:\/\/Bangla.SaLearningSchool.com<\/a><br \/>\n\t\t<a href='http:\/\/SitesTree.com' target='new' rel=\"noopener\">http:\/\/SitesTree.com<\/a><br \/>\n\t\t8112223 Canada Inc.\/JustEtc: <a href='http:\/\/JustEtc.net' target='new' rel=\"noopener\">http:\/\/JustEtc.net (Software\/Web\/Mobile\/Big-Data\/Machine Learning) <\/a><br \/>\n\t\tShop Online: <a href='https:\/\/www.ShopForSoul.com'> https:\/\/www.ShopForSoul.com\/<\/a><br \/>\n\t\tMedium: <a href='https:\/\/medium.com\/@SayedAhmedCanada' target='new' rel=\"noopener\"> https:\/\/medium.com\/@SayedAhmedCanada <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Objects provide encapsulation\/re-usability at the class level. A component can be comprised of multiple objects Component = logical groups of classes = distributed objects = business objects A component can be developed to address a specific enterprise applications. Hence, components can provide significant encapsulation\/re-usability in the partitioned enterprise problems. Component model = components + their &hellip; <\/p>\n<p><a class=\"more-link btn\" href=\"http:\/\/bangla.sitestree.com\/?p=66324\">Continue reading<\/a><\/p>\n","protected":false},"author":8,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[1917],"tags":[],"class_list":["post-66324","post","type-post","status-publish","format-standard","hentry","category-fromsitestree-com","item-wrap"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack-related-posts":[{"id":66340,"url":"http:\/\/bangla.sitestree.com\/?p=66340","url_meta":{"origin":66324,"position":0},"title":"Core J2EE Component Technologies #Java Short Notes","author":"Author-Check- Article-or-Video","date":"July 18, 2021","format":false,"excerpt":"Core J2EE Component Technologies J2EE Application Components: Web Components, Business Components Web-Component: Software entity hosted by a web-container on a J2EE Server Generate user interface for web-based applications Two Types: Servlets, JSPs Servlets: Process requests dynamically, format responses JSPs: How to process requests, and format responses Business Components: EJB Components\u2026","rel":"","context":"In &quot;FromSitesTree.com&quot;","block_context":{"text":"FromSitesTree.com","link":"http:\/\/bangla.sitestree.com\/?cat=1917"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":67690,"url":"http:\/\/bangla.sitestree.com\/?p=67690","url_meta":{"origin":66324,"position":1},"title":"Basic Java But Essential Knowledge for exams like SCJA, or to the project managers new to Java technologies #Computer Game Design #Java Short Notes","author":"Author-Check- Article-or-Video","date":"July 27, 2021","format":false,"excerpt":"By definition an enumerated type is a finite set of symbolic literals In Java an enumerated type is represented as first-class object. 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