book

EJB™ 2.1 Kick Start

by Peter Thaggard

November 2002

Intermediate to advanced

400 pages

8h 14m

English

Sams

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Dedication
RoadmapPrerequisites
The Problem with the Status QuoThe Knight in Shining Armor: EJBA New Approach to DevelopmentThe Business PlanBookEaz Business PlanDistinguishing CharacteristicsFeatures and Functions of the BusinessUse Cases LiteAnalysis Phase One: Catalog the System’s UsersAnalysis Phase Two: Catalog FunctionalityAnalysis Phase Three: Describe Functionality as Use CasesThe Analysis ModelUse Case Analysis of BookEazActor DictionaryUse Case Dictionary for BookEazShoppers’ Candidate Use CasesAdministrators’ Candidate Use CasesOrder Fulfillment’s Candidate Use CasesEmail System’s Candidate Use CasesBuilding the Analysis ModelThe Use Case DocumentUse Case Documentation FormatBookEaz Use Case DocumentUse Case 1: Perusing a Shopping PagePreconditionsPrimary FlowUse Case 2: Searching for a BookPreconditionsPrimary FlowSubflow 1: Search by AuthorSubflow 2: Search by TitleSubflow 3: Search by SubjectSubflow 4: Display Matching BooksSubflow 5: Display “Search Failed” MessageUse Case 3: Adding a Book to a CartPreconditionsPrimary FlowSubflow 1: User Decides Against Adding Book to CartUse Case 4: Reviewing Cart ContentsPreconditionsPrimary FlowSubFlow 1: Shopper Indicates Desire to Remove a BookSubFlow 2: Shopper Alters QuantityUse Case 5: Checking OutPreconditionsPrimary FlowSubflow 1: Shopper’s Identity Is KnownSubflow 2: Shopper’s Identity Is Not Yet KnownSubflow 3: Gather Payment InformationSubflow 4: Gather Shipping InformationSubflow 5: Confirming PurchaseUse Case 6: Maintaining the Inventory DatabasePrimary FlowSubflow 1: Wholesale Database UpdatesSubflow 2: Creating a New EntrySubflow 3: Deleting an EntrySubflow 4: Modifying an EntryAlternative Flow 1: Unable to Complete a Database OperationUse Case 7: Forwarding an OrderPreconditionsPrimary FlowUse Case 8: Sending an Email NotificationPreconditionsPrimary FlowConclusion
Logical Modeling: The Key to Designing EJB SystemsKeeping It Strictly BusinessBookEaz Sequence DiagramsSD1.0: Perusing a Shopping PageDiscoveriesSD2.0: Searching for a TitleDiscoveriesEntity Bean DefinitionEntity Bean Home InterfaceEntity Bean Remote InterfaceEntity Bean ImplementationDistributing BehaviorMaking a Class an Entity BeanSD3.0: Adding an Item to a CartDiscoveriesVariations on a Bean: Local ObjectsSD4.0: Reviewing Cart ContentsDiscoveriesSD5.0: Checking OutDiscoveriesA Bean of a Different Flavor: Session BeansSession Bean Home InterfaceSession Bean Remote InterfaceSession Bean ImplementationSD5.1: Detailed View of CheckoutDiscoveriesSD6.0: Wholesale Database UpdatesDiscoveriesSD7.0: Forwarding an OrderDiscoveriesMessage-Driven BeansJava Message Service (JMS) and Message-Driven BeansSD8.0: Email NotificationDiscoveriesConclusion
The EJB Runtime EnvironmentEJB Containers and Application ServersInstalling an Application Server and Deploying EJBs into ItDivide and ConquerTwo Flavors of Entity Beans: CMP Versus BMPContainer Managed Persistence BeansDeclaring Book’s Remote InterfaceDiscussionDeclaring Book’s Home InterfaceDiscussionImplementing BookBeanDiscussionCompiling Book’s Java CodePrerequisites for CompilingThe Rest of the Story: Deploying EJBsDeployment ToolsUsing deploytool to Deploy BookStep 1: Create an ApplicationStep 2: Create the Book EJBBookEaz’s Database Administrator ClientCompiling and Running BookAdministratorConclusion
Implementing Local Entity BeansCoding ShoppingItemShoppingItem’s Local Interface ImplementationShoppingItemHome’s ImplementationShoppingItemBean’s ImplementationDeploying Local EntitiesCompile ShoppingItem’s ConstituentsAdd ShoppingItem to the Book EJB JARConfigure General Information About ShoppingItemFill In the Entity Settings Dialog BoxBind ShoppingItem to a DatasourceDeploy ShoppingComplex Entity Bean RelationshipsLimits on RelationshipsShoppingCart’s Relationship with ShoppingItemShoppingItem’s Relationship with BookImplementing and Deploying ShoppingCartShoppingCart’s Remote Interface ImplementationShoppingCartHome’s ImplementationShoppingCartBean’s ImplementationDeploying ShoppingCartCompile the CodeAdd ShoppingCart to the Shopping JARConfigure General Information About ShoppingCartFill in the Entity Settings Dialog BoxInform DeployTool of ShoppingCart’s Use of ShoppingItemHomeDefine the ShoppingCart-to-ShoppingItem RelationshipBind ShoppingCart to a DatasourceDeploy ShoppingTest ShoppingCartInstalling Predeployed EJBsDownload ejb-jar-ic2.jarAdd Order’s JAR to the ContainerModify Order and LineItem to Coexist with the ContainerAssign JNDI Names to Order and LineItemConclusion

Coding CheckoutCheckout Remote InterfaceCheckout Home InterfaceCheckout ImplementationDesign Compromise: Getting a ShoppingCart’s ShoppingItemsGetting HomeDeploying Session BeansCompile Checkout’s Java ComponentsCreate a New JAR to House CheckoutInform DeployTool That Checkout Is a Session BeanConfigure Checkout’s Transaction Management ResponsibilitiesAdd References to ShoppingItemHome and OrderHomeImplementing Message-Driven BeansBeans of a Slightly Different FlavorDeploying Message-Driven BeansStep 1: Compile FulfillmentBean.javaStep 2: Create Fulfillment.JARStep 3: Set the Bean’s Type to MDBStep 4: Configure Transaction ManagementStep 5: Configuring FulfillmentBean’s Message QueueConclusion
Deployment OverviewDeployment UnitsEAR File ContentsReferences Between ComponentsThe ejb-jar.xml Deployment Descriptor FileHeader ElementsMandatory Element: <?xml>Optional Element: <!DOCTYPE>Mandatory Section: <ejb-jar>Mandatory Section: <enterprise-beans>Defining a Session Bean with <session>Optional Element: <description>Optional Element: <display-name>Optional Element: <small-icon>Optional Element: <large-icon>Mandatory Element: <ejb-name>Optional Element: <home>Optional Element: <remote>Optional Element: <local-home>Optional Element: <local>Optional Element: <service-endpoint>Mandatory Element: <ejb-class>Mandatory Element: <session-type>Mandatory Element: <transaction-type>Optional Section: <env-entry>Optional Section: <ejb-ref>Optional Section: <ejb-local-ref>Optional Section: <service-ref>Optional Section: <security-role-ref>Optional Section: <security-identity>Optional Section: <resource-ref>Optional Section: <resource-env-ref>Optional Section: <message-destination-ref>Defining an Entity Bean with <entity>Optional Element: <description>Optional Element: <display-name>Optional Element: <small-icon>Optional Element: <large-icon>Mandatory Element: <ejb-name>Optional Element: <home>Optional Element: <remote>Optional Element: <local-home>Optional Element: <local>Mandatory Element: <ejb-class>Mandatory Element: <persistence-type>Mandatory Element: <prim-key-class>Mandatory Element: <reentrant>Optional Element: <cmp-version>Optional Element: <abstract-schema-name>Optional Elements: <cmp-field>Optional Element: <primkey-field>Optional Section: <env-entry>Optional Section: <ejb-ref>Optional Section: <ejb-local-ref>Optional Section: <service-ref>Optional Section: <security-role-ref>Optional Section: <security-identity>Optional Section: <resource-ref>Optional Section: <resource-env-ref>Optional Section: <message-destination-ref>Optional Sections: <query>Defining a Message-Driven Bean with <message-driven>Optional Element: <description>Optional Element: <display-name>Optional Element: <small-icon>Optional Element: <large-icon>Mandatory Element: <ejb-name>Mandatory Element: <ejb-class>Optional Element: <messaging-type>Mandatory Element: <transaction-type>Optional Element: <message-selector>Optional Element: <acknowledge-mode>Mandatory Section: <message-driven-destination>Optional Section: <env-entry>Optional Section: <ejb-ref>Optional Section: <ejb-local-ref>Optional Section: <service-ref>Optional Section: <security-role-ref>Optional Section: <security-identity>Optional Section: <resource-ref>Optional Section: <resource-env-ref>Optional Section: <message-destination-ref>Describing Container Managed Relationships (CMR)Optional Section: <relationships>Mandatory Section: <ejb-relation>Optional Element: <description>“Virtually Mandatory” Element: <ejb-relation-name>Mandatory Section: <ejb-relationship-role>This Role and the Other RoleOptional Element: <description>“Virtually Mandatory” Element: <ejb-relationship-role-name>Mandatory Element: <multiplicity>Optional Element: <cascade-delete/>Mandatory Section: <relationship-role-source>Mandatory Section: <cmr-field>Assembling EJBs: Security and TransactionsOptional Section: <assembly-descriptor>Optional Section: <security-role>Optional Section: <method-permission>Mandatory Section: <method>Declaring Transactions with <container-transaction>Optional Section: <container-transaction>Optional Section: <message-destination>Conclusion
Compiling and Running Chapter 7’s ExamplesRemote/Local InterfacesRemote Interface Container-Supplied MethodsEJBObject.getEJBHome()EJBObject.getHandle()methodEJBObject.getPrimaryKey()methodEJBObject.isIdentical()EJBObject.remove()methodRemote Interface Getters, Setters, and Business MethodsLocal Interface Container-Supplied MethodsLocal Interface Getters, Setters, and Business MethodsRemote and Local Home InterfacesRemote Home Interface Container-Supplied MethodsEJBHome.getEJBMetaData()EJBHome.getHomeHandle()EJBHome.remove() MethodsCreate MethodsRemote Home Interface Finder MethodsRemote Home Interface Home MethodsLocal Home Interface’s Remove MethodLocal Home Interface’s Create, Finder, and Home MethodsEntity Bean ImplementationsCMP ImplementationsCMP Implementations of Getters and SettersCMP Implementations of Business MethodsCMP ejbcreate...() MethodsCMP ejbPostCreate...() MethodsCMP remove() MethodsCMP ejbActivate() MethodsCMP ejbPassivate() MethodsCMP ejbLoad() MethodsCMP ejbStore() MethodsCMP setEntityContext() MethodsCMP unsetEntityContext() MethodsCMP Implementations of ejbTimeOut()CMP Implementations of Home MethodsCMP select...() MethodsCMP find...() MethodsEJB QL “Lite”: Defining Finders and Selectors with EJB QLAbstract SchemasEJB QL SyntaxThe SELECT ClauseThe FROM ClauseThe WHERE clauseThe ORDER BY ClauseFor More InformationBMP ImplementationsBMP Implementations of Attributes, Getters, and SettersBMP Implementations of Business MethodsBMP create...() MethodsBMP PostCreate() MethodsBMP ejbRemove() MethodsBMP ejbActivate() MethodsBMP ejbPassivate() MethodsBMP ejbLoad() MethodsBMP ejbStore() MethodsBMP setEntityContext() MethodsBMP unsetEntityContext() MethodsBMP Implementations of ejbTimeOut()BMP Implementations of Home MethodsBMP select...() MethodsBMP find...() Methods
Compiling and Running the ExamplesStateful and Stateless Session BeansSession Bean Component InterfaceSession Bean Remote Interface Container-Supplied MethodsRemote Versus Very Distant ClientsThe EJBObject.getEJBHome() MethodThe EJBObject.getHandle() MethodThe EJBObject.isIdentical() MethodThe EJBObject.remove() MethodBusiness Method Declarations in Session Bean Remote InterfacesLocal Interface Container-Supplied MethodsBusiness Method Declarations in Session Bean Local InterfacesBusiness Method Declarations in Web Service Endpoint InterfacesRemote and Local Session Bean Home InterfacesRemote Home Interface Container-Supplied MethodsThe EJBHome.getEJBMetaData() MethodThe EJBHome.getHomeHandle() MethodThe EJBHome.remove() MethodCreate MethodsThe Local Home Interface’s remove() MethodThe Local Home Interface’s create...() MethodSession Bean ImplementationsBusiness Method ImplementationsSession Bean ejbCreate...() ImplementationsSession Bean Life-Cycle Management MethodsThe setSessionContext() MethodThe ejbPassivate() MethodThe ejbActivate() MethodThe ejbRemove() MethodCommon Session Bean Implementation PracticesSession Beans Manipulating DatabasesSession Beans Using Other Session BeansAcquiring Resources at Bean Creation TimeUse Local Beans Whenever PossibleConclusion
Queues and TopicsMDB StructureThe Two Interfaces of MDBsThe onMessage() MethodJAXM Message-Processing MethodsResponding to Timer Service EventsThe ejbCreate() MethodThe ejbRemove() MethodThe setMessageDrivenContext() MethodThe MessageDrivenContext.setRollbackOnly() MethodThe boolean getRollbackOnly() MethodThe javax.transaction.UserTransaction getUserTransaction() MethodMDB Best PracticesUse MDBs to Interact with Legacy SystemsFire-and-ForgetConclusion
Web Services OverviewWeb Service ComponentsWeb Service ImplementationsWeb Service RegistriesWeb Service DescriptionsWeb Service Invocation MechanismWeb Service Message FormatImplementing Web Services As Session BeansWeb Service Endpoint InterfaceSession Bean ImplementationWeb Service Deployment DescriptorEJB 2.1 Timer ServiceCreating a Timed ObjectRegistering Interest in Timed EventsReceiving and Processing Timer NotificationsEJB Type and Timer BehaviorConclusion
Models and DiagramsModeling ToolsDocumenting Analysis with Use Cases and Scenario DiagramsSequence Diagrams: Showing the Order of InteractionsSequence Diagram InstancesMessagesNarrativeUsing Sequence Diagrams During the Design PhaseCollaboration DiagramsInstance DiagramsStatic and Dynamic RelationshipsClass DiagramsClassesName Compartment and StereotypesAttributes CompartmentOperations CompartmentRelationshipsBidirectional AssociationUnidirectional AssociationExtends RelationshipImplements RelationshipDepends RelationshipConclusion
Obtaining and Installing the Reference ServerInstalling the Reference Server on WindowsStarting the Reference ServerUsing j2EEadmin to Configure the Reference ServerAdd Cloudscape’s JDBC DriverAdd BookEaz’s BooksInCloudscape JDBC Datasource
Installing WebLogic Server 6.1, Service Pack 2Obtaining and Installing WebLogic Server 6.1Configuring Cloudscape for WebLogic Server 6.1Installing WebLogic Server 7.0Creating BookEazDomain in WebLogic Server 7.0Configuring PointBase 4.2 Database ServerConfiguring the Server via WebLogic’s ConsoleAdd the Database Cloudscape Connection PoolAdd BookEaz’s Cloudscape JDBC DatasourceAdd FulfillmentBean’s JMS Connection FactoryAdd FulfillmentBean’s Message QueueConclusion

Content preview from EJB™ 2.1 Kick Start

Chapter 7. Entity Beans

IN THIS CHAPTER

An Entity Bean is an abstraction representing a state-laden class whose instances are stored in a persistence mechanism such as a relational database. Generally speaking, if a class’s state (that is, its attributes) is more important than its behavior (that is, its methods), then the class is amenable to being implemented as an Entity Bean. BookEaz’s system contained several Entity Beans, including Book, ShoppingCart, ShoppingItem, Order, and LineItem. These abstractions from BookEaz’s business domain all pass the “state is more important than behavior” litmus test.

Every instance of an Entity Bean has a unique identity that ...