MIDDLE WARE TECHNOLOGIES
B.TECH III YR II SEMESTER
UNIT 8 PPT SLIDESTEXT BOOKS:
1.Client/Server programming with Java and CORBA Robert Orfali and Dan Harkey, John Wiley & Sons,SPD 2nd Edition2. Java programming with CORBA 3rd Edition, G.Brose, A Vogel and K.Duddy, Wiley-dreamtech, India John wiley and sons
INDEX UNIT 1 PPT SLIDES
S.NO. TOPIC LECTURE NO. PPTSLIDES
1. Object transaction monitors L58 L1.1 to L1.4 L59 L2.1 TO L2.42. EJB and CORBA OTM’s L60 L3.1 TO L3.3 L61 L4.1 TO L4.2
3. session and Entity Beans L62 L5.1 TO L5.2
4. The EJB client/server development L63 L6.1 TO L6.25. EJB container protocol L64 L7.1 TO L7.2
6. EJB packing L65 L8.1 TO L8.2
UNIT8 SYLLABUS
• EJBS and COBRA:
• Object transaction monitors CORBA OTM’s EJB and CORBA OTM’s EJB container frame work, session and Entity Beans, The EJB client/server development processes the EJB container protocol, support for transaction EJB packing EJB design Guidelines.
Lecture 1 slide 1
EJB DEFINITION
• EJB IS A STNDARD SPECIFICATION WHICH
ALLOWS US TO DEVELOP A DISTRIBUTED TRANSACTIONAL SECURE COMPONENTS IN JAVA
Lecture 1 slide 2
EJB COMPONENT
IS A COMBINATION OF SOMECLASSES AND INTERFACES DESIGNED FOLLOWING THE EJB SPECIFICATION STANDARDS.
Lecture 1 slide 3
EJB CONTAINER
is a readymade platform which is a rich of all the low-level services which can provide runtime environment for ejb components.
Lecture 1 slide 4
EJBS AND CORBA
• Enterprise JavaBeans and CORBA • Object transaction monitors, CORBA OTM’s, EJB and
CORBA OTM’s, EJB container F/W, session and Entity beans, The EJB C/S development process, The EJB container protocol, support for transaction, EJB packaging, EJB design guidelines.
• OTMs• An OTM is a morph of TP monitor with an ORB.• Or, in other words, it is a TP monitor built on top of an
ORB.• An ORB is simply an object bus, with an object bus,
anytime goes, in contrast, an OTM provides a framework, for running server-side components.
Lecture 2 slide 1
EJBS AND CORBA
• Procedural Vs F/W Appraches to Developing code
• Advantages of OTM’s approach: Yours objects become managed transactional, robust , persistent and high-performing.
• Functions of OTM:• Activates and deactivates your components• Coordinates distributed transactions.• Notifies your component of key events during its
life style.
Lecture 2 slide 2
EJBS AND CORBA• Automatically manages the state of your persistent component.• CORBA OTM’s : from four groups• TP Monitor vendors moving to ORB-based middleware.• ex: BEA Iceberg, IBM component broker.• DBMS Vendors moving from 2-tier to 3-tier.• ex: oracle app. Server 4.0, Gene stone/J, Sybase/jaguar.• ORB vendors moving from pipes to TP – based app. servers.• ex: Iona orbix OTM, Visigenic/Borland ITS• Web server vendors moving to TP-based app. servers• ex: Net Dynamics App. server 4.0, Netscape Enterprise server
4.0/kiva, sapphire/web 4.0
Lecture 2 slide 3
EJBS AND CORBA
• EJBs and CORBA OTMs:• EJB defines a server side component model and
a comp. coordinator f/w that is totally compatible with CORBA.
• The EJB Container F/W• The major functions a server-side container (or
OTM) provides to the EJBs that run within it.• Packaging• Dist.obj.infrastructure• Comp.packaging and deployment• Declarative trans. Mgnt.
Lecture 2 slide 4
EJBS AND CORBA
• Factory support
• Bean activation and persivation
• Bean state mgnt.
• Container metadata
• Security
• Session and Entity Beans:
• Characteristics of a session bean
Lecture 3 slide 1
EJBS AND CORBA
• Executes on behalf of a single client• Can be transaction – aware• Updates data in an underlying data base.• Relatively short-lived, life time is that of its
client.• Destroyed when the EJB server crashes;
client has to a new session• Does not represent data that should be
stored in a data base.
Lecture 3 slide 2
EJBS AND CORBA
• Characteristics of an Entity bean• Supports shared access from multiple users.• Participates in transactions• Represents data in the data base.• Can be ling-lived (as long as the data base).• Survives crashes of the EJB server; crash
transparent to the client• Has a persistent obj.ref.
Lecture 3 slide 3
EJBS AND CORBA
• EJB Packaging– Extends the existing javabeans packaging technology
to take car of the needs of server side beans.– EJB packaging can be used to distribute a single
enterprise bean or to distribute an entire server-side application built of multiple enterprise beans.
– EJB-JAR and manifest – list-java file contains• EJB’s class files• Deploy base• Manifest that identifier the enterprise bean included in the
JAR.
Lecture 4 slide 1
EJBS AND CORBA
• The manifest is named META-INF/MANIFEST.MF.
• EJB Design Conditions:• Your remote interface must follow the
CoRBA/MI/IDL subset.• Define a remote interface.• Dont mess around threads• Don’t issue commits or roll backs.• Give your containers a full EJB-jar package.
Lecture 4 slide 2
EJB ARCHITECTURE
Lecture 5 slide 1
FRAMEWORK
Lecture 5 slide 2
OTM
Lecture 6 slide 1
EJB container class
Lecture 6 slide 2
EJB client/server process
Lecture 7 slide 1
The remote EJB interface
Lecture 7 slide 2
EJB deployment classe
Lecture 8 slide 1
IDL interface and stubs
Lecture 8 slide 2
Java classes and interfaces
