Oracle Fusion MiddlewareUnderstanding Oracle WebLogic Server14c ( 2021

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ContentsPreface12Documentation t Overview1-1Programming Models1-2High Availability1-3Diagnostic Framework1-4Security1-4Client Options1-5Integration with Oracle WebLogic Suite1-5Integration with Other Systems1-6Integration with Web Servers1-6Running Oracle WebLogic Server on Docker1-6WebLogic Deploy Tooling1-6WebLogic Image Tool1-6WebLogic Server Kubernetes Operator1-7WebLogic Monitoring Exporter1-7WebLogic Logging Exporter1-7WebLogic Server API Examples and Sample Application1-7Upgrade1-8System AdministrationOverview of WebLogic Server System Administration2-1Choosing the Appropriate Technology for Your Administrative Tasks2-1Summary of System Administration Tools and APIs2-5Roadmap for Administering the WebLogic Server System2-8iii

3Overview of Administration ConsolesUsing the WebLogic Server Administration Console43-1About the WebLogic Server Administration Console3-1Starting the WebLogic Server Administration Console3-2Enabling the WebLogic Server Administration Console3-3Elements of the WebLogic Server Administration Console3-3Using the Change Center3-6WebLogic Server DomainsUnderstanding Domains4-1Organizing Domains4-1Contents of a Domain4-3Administration Server4-3Managed Servers and Managed Server Clusters4-4Managed Coherence Servers and Coherence Clusters4-4Resources and Services4-4Roadmap for Understanding WebLogic Server Domains5674-5WebLogic Server ClusteringOverview of WebLogic Server Clusters5-1Relationship Between Clusters and Domains5-1Relationship Between Coherence and WebLogic Server Clusters5-2Benefits of Clustering5-2Key Capabilities of Clusters5-3Objects That Can Be Clustered5-3About Dynamic Clusters5-4Roadmap for Clustering in WebLogic Server5-4Developing Applications in WebLogic ServerWebLogic Server and the Java EE Platform6-1Overview of Java EE Applications and Modules6-2Roadmap for Developing Applications in WebLogic Server6-3Deploying Applications in WebLogic ServerOverview of the Deployment Process7-1Java EE Deployment Implementation7-1Fast Track Deployment Guide7-3iv

Java EE Deployment7-3Auto-Deployment7-3Deploying Multiple Applications7-4System Administrator Tools7-4JSP/HTML Deployment7-4Coherence Deployment7-5Roadmap for Deploying Applications in WebLogic Server8910117-5WebLogic Server Data SourcesUnderstanding JDBC Data Sources8-1Understanding Generic Data Sources8-2Understanding Active GridLink Data Sources8-2Understanding JDBC Multi Data Sources8-2Understanding Proxy Data Sources8-2Understanding Universal Connection Pool Data Sources8-3Roadmap for WebLogic Server Data Sources8-3WebLogic Server MessagingOverview of JMS and WebLogic Server9-1Java Message Service9-1Roadmap for WebLogic Server Messaging9-3Understanding WebLogic Server SecurityJSR 375 Security API Support in WebLogic Server10-1Overview of the WebLogic Server Security Service10-2WebLogic Server Security Service Architecture10-3WebLogic Security Framework10-3Single Sign-on with the WebLogic Server Security Framework10-5SAML Token Profile Support in WebLogic Web Services10-5The Security Service Provider Interfaces (SSPIs)10-5WebLogic Security Providers10-6Managing WebLogic Server Security10-6Security for Coherence10-7Roadmap for Securing WebLogic Server10-7WebLogic Server Web ServicesAnatomy of a Web Service11-1Web Service Standards11-2v

Roadmap for Web Services1211-2Enterprise JavaBeans (EJBs)Understanding EJBs12-1EJB Documentation in WebLogic Server12-1Additional EJB Information12-2Session EJBs Implement Business Logic12-2Message-Driven Beans Implement Loosely Coupled Business Logic12-3EJB Anatomy and Environment12-3EJB Components12-4The EJB Container12-5Embeddable EJB Container12-5EJB Metadata Annotations12-5Optional EJB Deployment Descriptors12-5EJBs Clients and Communications131412-6Accessing EJBs12-6EJB Communications12-7Securing EJBs12-7Roadmap for EJBs in WebLogic Server12-8Monitoring, Diagnosing, and TroubleshootingWebLogic Diagnostics Framework13-1Logging Services13-2SNMP Support13-3Custom JMX Applications13-3Java EE Management APIs13-3Roadmap for Monitoring, Diagnosing, and Troubleshooting in WebLogic Server13-4Sample Applications and Code ExamplesInstalling and Running the Examples14-1Installing the WebLogic Server Code Examples14-1Starting the WebLogic Server Samples Domain14-2Running the WebLogic Server Code Examples14-2Conventions14-2Java EE 8 Examples14-3Java EE 7 Examples14-4Additional API Examples14-5Avitek Medical Records14-5vi

Derby Open-Source Database1514-6WebLogic Server CompatibilityJava EE 8 Compatibility15-1Generated Classes Compatibility15-1Compatibility Within a Domain15-1About WebLogic Server Version Numbers15-2WebLogic Version Compatibility15-2Hardware, Operating System, and JVM Platform Compatibility15-3Node Manager Compatibility15-4Persistent Data Compatibility15-4API Compatibility15-4Protocol Compatibility15-4vii

PrefacePrefaceThis preface describes the document accessibility features and conventions used inthis guide—Understanding Oracle WebLogic Server.Documentation AccessibilityFor information about Oracle's commitment to accessibility, visit the OracleAccessibility Program website at acc&id docacc.Access to Oracle SupportOracle customers that have purchased support have access to electronic supportthrough My Oracle Support. For information, visit acc&id info or visit acc&id trs if you are hearing impaired.ConventionsThe following text conventions are used in this document:ConventionMeaningboldfaceBoldface type indicates graphical user interface elements associatedwith an action, or terms defined in text or the glossary.italicItalic type indicates book titles, emphasis, or placeholder variables forwhich you supply particular values.monospaceMonospace type indicates commands within a paragraph, URLs, codein examples, text that appears on the screen, or text that you enter.viii

1IntroductionOracle WebLogic Server is the industry's best application server for building and deployingenterprise Java EE applications with support for new features for lowering cost of operations,improving performance, enhancing scalability and supporting the Oracle Applicationsportfolio.The following sections provide an overview of Oracle WebLogic Server features and describehow you can use them to create enterprise ready-solutions: Product Overview Programming Models High Availability Diagnostic Framework Security Client Options Integration with Oracle WebLogic Suite Integration with Other Systems Integration with Web Servers Running Oracle WebLogic Server on Docker WebLogic Image Tool WebLogic Server Kubernetes Operator WebLogic Deploy Tooling WebLogic Monitoring Exporter WebLogic Logging Exporter WebLogic Server API Examples and Sample Application UpgradeProduct OverviewOracle WebLogic Server provides a modern development platform for building applications, aruntime platform for high performance and availability, and rich management tooling forefficient and low cost operations.The WebLogic Server complete implementation of the Java Platform, Enterprise Edition 8(Java EE 8) specification provides a standard set of APIs for creating distributed Javaapplications that can access a wide variety of services, such as databases, messagingservices, and connections to external enterprise systems. End-user clients access theseapplications using web browser clients or Java clients. See Programming Models.In addition to the Java EE implementation, WebLogic Server enables enterprises to deploymission-critical applications in a robust, secure, highly available, and scalable environment.1-1

Chapter 1Programming ModelsThese features allow enterprises to configure clusters of WebLogic Server instances todistribute load, and provide extra capacity in case of hardware or other failures. Newdiagnostic tools allow system administrators to monitor and tune the performance ofdeployed applications and the WebLogic Server environment itself. You can alsoconfigure WebLogic Server to monitor and tune application throughput automaticallywithout human intervention. Extensive security features protect access to services,keep enterprise data secure, and prevent malicious attacks.Figure 1-1 shows how WebLogic Server fits into the overall Oracle Fusion Middlewarestack.Figure 1-1Oracle Fusion Middleware OverviewProgramming ModelsOracle WebLogic Server provides complete support for the Java Enterprise Edition 8(Java EE 8) platform, which reduces the complexity of enterprise applicationdevelopment by providing a development model, API, and runtime environment thatallow developers to concentrate on functionality. The Java EE 8 specification isavailable at rview/indexjsp-135147.html. For information about Java EE programming model support inWebLogic Server, see the following programming guides: Web Applications provide the basic Java EE mechanism for deployment ofdynamic web pages based on the Java EE standards of servlets and JavaServer1-2

Chapter 1High AvailabilityPages (JSP). Web applications are also used to serve static web content such as HTMLpages and image files. Web Services provide a shared set of functions that are available to other systems on anetwork and can be used as a component of distributed web-based applications. XML capabilities include data exchange, and a means to store content independent of itspresentation, and more. Java Messaging Service (JMS) enables applications to communicate with one anotherthrough the exchange of messages. A message is a request, report, and/or event thatcontains information needed to coordinate communication between different applications. Java Database Connectivity (JDBC) provides pooled access to DBMS resources. Resource Adapters provide connectivity to Enterprise Information Systems (EISes). Enterprise JavaBeans (EJB) provide Java objects to encapsulate data and businesslogic. Remote Method Invocation (RMI) is the Java standard for distributed object computing,allowing applications to invoke methods on a remote object locally. Security APIs allow you to integrate authentication and authorization into your Java EEapplications. You can also use the Security Provider APIs to create your own customsecurity providers. WebLogic Tuxedo Connectivity (WTC) provides interoperability between WebLogicServer applications and Tuxedo services. WTC allows WebLogic Server clients to invokeTuxedo services and Tuxedo clients to invoke EJBs in response to a service request. Coherence provides distributed caching and data grid capabilities for WebLogic Serverapplications. Overview of WebLogic Server Application Development describes developer tools andbest practices for coding WebLogic Server applications.High AvailabilityOracle WebLogic Server provides several features and tools to support the deployment ofhighly-available applications that can be automatically scaled to meet demand in a reliableand fault-tolerant manner. The high availability features provided in WebLogic Server includethe following: WebLogic Server clusters provide scalability and reliability for your applications bydistributing the work load among multiple instances of WebLogic Server. Incomingrequests can be routed to a WebLogic Server instance in the cluster based on thevolume of work being processed. In case of hardware or other failures, session state isavailable to other cluster nodes that can resume the work of the failed node. In addition,you can implement clusters so that services may be hosted on a single machine withoptions to migrate the service to another node in the event of failure.In addition to replicating HTTP session state across servers within a cluster, WebLogicServer can also replicate HTTP session state across multiple clusters, thereby expandingavailability and fault tolerance in multiple geographic regions, power grids, and Internetservice providers. Elasticity in dynamic clusters enables the automatic scaling of dynamic clusters and reprovisioning of their associated resources. The elasticity framework leverages theWebLogic Diagnostic Framework (WLDF) policies and actions system.1-3

Chapter 1Diagnostic Framework Coherence clusters provide scalability and fault tolerance by distributing dataacross any number of cluster members ensuring that data is always available andeasily accessed by any application hosted in WebLogic Server.In addition, Web applications can choose to use a Coherence data grid for storingand replicating HTTP session state to improve scalability, fault tolerance, andperformance. Work Managers prioritize work based on rules you define and by monitoring actualrun time performance statistics. This information is then used to optimize theperformance of your application. Work Managers may be applied globally to aWebLogic Server domain or to a specific application or component. Overload protection gives WebLogic Server the ability to detect, avoid, andrecover from overload conditions. Network channels facilitate the effective use of network resources by segregatingnetwork traffic into channels based on the type of traffic. Simplified JMS cluster configuration and high availability allows applications toeasily scale WebLogic JMS services such as JMS servers, SAF agents, andpersistent stores. Cluster-targeted JMS servers and persistent stores allowtargeting the JMS service artifacts directly to the cluster and eliminate the need toconfigure artifacts individually for every server in a cluster. WebLogic Server persistent store is a built-in, high-performance storage solutionfor WebLogic Server subsystems and services that require persistence. Forexample, it can store persistent JMS messages or temporarily store messagessent using the Store-and-Forward feature. The persistent store supportspersistence to a file-based store or to a JDBC-enabled database. Store-and-forward services enable WebLogic Server to deliver messages reliablybetween applications that are distributed across WebLogic Server instances. If themessage destination is not available at the moment the messages are sent, eitherbecause of network problems or system failures, then the messages are saved ona local server instance and are forwarded to the remote destination once itbecomes available. Enterprise-ready deployment tools facilitate deployment and migration ofapplications from the development phase to a production environment. Production redeployment enables enterprises to deploy a new version of theirapplication without interrupting work in progress on the older version.Diagnostic FrameworkThe WebLogic Diagnostic Framework is a monitoring and diagnostic service that letsyou create, collect, analyze, archive, and access diagnostic data generated by arunning WebLogic Server instance and applications deployed on it. This diagnosticdata provides insight into the runtime performance of WebLogic Server instances, anddeployed applications, which helps you isolate and diagnose faults and performancebottlenecks when they occur. See What Is the WebLogic Diagnostics Framework? inConfiguring and Using the Diagnostics Framework for Oracle WebLogic Server.SecurityThe WebLogic Server security architecture provides a comprehensive, flexible securityinfrastructure designed to address the security challenges of making applications1-4

Chapter 1Client Optionsavailable on the Internet. WebLogic security can be used standalone to secure WebLogicServer applications, or as part of an enterprise-wide, security management system thatrepresents a best-in-breed security management solution. See Overview of the WebLogicSecurity Service in Understanding Security for Oracle WebLogic Server for more information.Client OptionsIn addition to support for browser-based web application clients, WebLogic Server alsosupports a variety of client types for creating rich GUI applications or simple command-lineutilities. These client types include: RMI-IIOP, T3, Java SE clients, Java EE thin clients,CORBA/IDL clients, and C clients that communicate with BEA Tuxedo. See Overview ofStandalone Clients in Developing Standalone Clients for Oracle WebLogic Server for moreinformation.Integration with Oracle WebLogic SuiteWebLogic Server provides the core application server runtime within the integrated OracleWebLogic Suite Java infrastructure. This integrated infrastructure enhances applicationperformance, improves application availability, and enables predictable and reliableapplication scalability with high quality of service. WebLogic Suite includes highly productivedevelopment tools based on Oracle JDeveloper and Oracle Enterprise Pack for Eclipse, andfully integrated management for large-scale administration and operations with OracleEnterprise Manager. Taken together, the development, runtime and management capabilitiesof WebLogic Suite provide the foundation for implementing mission-critical enterpriseapplications.WebLogic Suite contains the following server-side components: Oracle WebLogic Server Oracle CoherenceOracle Coherence enables organizations to predictably scale mission-critical applicationsby providing fast and reliable access to frequently used data. By automatically anddynamically partitioning data in memory across multiple servers, Oracle Coherenceenables continuous data availability and transactional integrity, even in the event of aserver failure.WebLogic Server includes a Coherence container that simplifies the management anddeployment of Coherence clusters and Coherence-based applications. Overview of TopLinkOracle TopLink builds high-performance applications that store persistent object-orienteddata in a relational database. It successfully transforms object-oriented data into eitherrelational data or Extensible Markup Language (XML) elements.Oracle TopLink is an advanced, object-persistence and object-transformation frameworkthat provides development tools and run time capabilities that reduce development andmaintenance efforts, and increase enterprise application functionality.Oracle TopLink includes support for EJB 3.0 in Java EE and Java SE environments, aswell as support for EJB 2.n container-managed persistence (CMP). You can integrateOracle TopLink with a variety of application servers, including Oracle WebLogic Server,JBoss Application Server, and IBM WebSphere Application Server.1-5

Chapter 1Integration with Other SystemsIntegration with Other SystemsWebLogic Server provides a variety of tools to integrate your applications withdisparate systems. These tools include web services, resource adapters, theJMS .NET client, the JMS C client, tooling for integrating JMS providers options,advanced queuing, and RMI.Integration with Web ServersYour WebLogic Server installation includes a set of web server plug-ins that allowrequests to Oracle WebLogic Server to be proxied from Oracle HTTP Server, ApacheHTTP Server, or Microsoft Internet Information Server (IIS). Typically, these webservers serve static HTML content, while requests for dynamic web content, such asJSPs, are directed to the WebLogic Server environment.Running Oracle WebLogic Server on DockerDocker is a Linux-based container technology that enables you to quickly createlightweight clustered and nonclustered WebLogic Server domain configurations on asingle or multi host OS, or virtual machines, for either development or productionenvironments. Oracle provides Dockerfiles and supporting scripts for building imagesof Oracle WebLogic Server. These images are built as an extension of existing OracleLinux and Server JRE images. These scripts and Dockerfiles are available on GitHubat the following location: r/OracleWebLogic.For information about using Docker with WebLogic Server, and the combinations ofOracle WebLogic Server, JDK, Linux and Docker versions that are certified for buildingyour Docker images, see the Supported Virtualization and Partitioning Technologies forOracle Fusion Middleware.WebLogic Deploy ToolingThe Oracle WebLogic Deploy Tooling (WDT) simplifies the automation of WebLogicServer domain provisioning and applications deployment.WDT creates a declarative, metadata model that describes the domain, applications,and resources used by applications. This metadata model makes it easy to provision,deploy, and perform domain lifecycle operations in a repeatable fashion. You can useWDT to migrate on-premises domain configuration and applications to a Docker imageor a persistent volume in Kubernetes. For complete documentation and samples, seethe open source WebLogic Deploy Tooling project in GitHub. Or, for a step-by-stepguide, read the blog, Make WebLogic Domain Provisioning and Deployment Easy!.WebLogic Image ToolThe Oracle WebLogic Image Tool lets you automate building, patching, and updatingyour WebLogic Server Docker images, including your own customized images.With the WebLogic Image Tool, you can: Create a customized WebLogic Server and FMW Infrastructure Docker image.1-6

Chapter 1WebLogic Server Kubernetes Operator Patch a base install image of WebLogic Server or FMW Infrastructure. Patch and build a domain image of WebLogic Server or FMW Infrastructure using aWebLogic Deploy Tool (WDT) model. Deploy an application and update the domain configuration.In addition, you can incorporate these use cases into an automated process for patching andupdating your WebLogic Server infrastructure and applications running in Docker andKubernetes. Find the open source WebLogic Image Tool GitHub project at ogic Server Kubernetes OperatorThe Oracle WebLogic Server Kubernetes Operator is an application-specific controller thatextends Kubernetes to create, configure, and manage instances of complex applications. Theoperator follows the standard Kubernetes operator pattern, and simplifies the managementand operation of WebLogic domains and deployments. The operator uses a common set ofKubernetes APIs to provide an improved user experience when automating operations suchas provisioning, life cycle management, application versioning, product patching, scaling, andsecurity.The operator is developed as an open source project fully supported by Oracle. The fastestway to experience the operator is to follow the Quick Start guide. Alternatively, you canperuse the documentation, read the blogs, or try out the samples. For project scripts,additional samples, and source files, see the Oracle WebLogic Server Kubernetes OperatorGitHub repository.WebLogic Monitoring ExporterThe Oracle WebLogic Monitoring Exporter is a web application that you can deploy on aWebLogic Server instance that you want to monitor.The exporter uses the WebLogic Server RESTful Management Interface for accessingruntime state and metrics and then exports Prometheus-compatible metrics, which can bedisplayed in Grafana dashboards for monitoring. For practical examples, see these blogposts: Exporting Metrics from WebLogic Server and Using Prometheus and Grafana toMonitor WebLogic Server on Kubernetes. For a detailed description of the Oracle WebLogicMonitoring Exporter, see the WebLogic Monitoring Exporter project in GitHub.WebLogic Logging ExporterThe Oracle WebLogic Logging Exporter provides an easy to configure, robust, andproduction-ready solution to access WebLogic Server log information through Elasticsearchand displayed in Kibana dashboards.Find the build and installation instructions in the open source WebLogic Logging Exporterproject README at r.WebLogic Server API Examples and Sample ApplicationOracle WebLogic Server includes a comprehensive set of code examples and sampleapplications that show how to implement Java EE APIs and Oracle WebLogic Server-specificfeatures in your applications. Code examples demonstrating Java EE APIs and other1-7

Chapter 1UpgradeWebLogic Server features are provided with your WebLogic Server installation. Towork with these examples, select the custom installation option when InstallingWebLogic Server, and select to install the Server Examples. To access the codeexamples, launch the startWebLogicEx.cmd or script fromORACLE HOME/user projects/domains/wl server, where ORACLE HOME is the directoryyou specified as the Oracle Home when you installed Oracle WebLogic. As theybecome available, you can also download additional examples.Along with the code examples, two versions of a complete sample application, calledAvitek Medical Records (or MedRec), are installed when you install the examples, asdescribed above.The original MedRec (which was included in previous versions of WebLogic Server) isa WebLogic Server sample application suite that concisely demonstrates all aspects ofthe Java EE platform. MedRec is designed as an educational tool for all levels of JavaEE developers. It showcases the use of each Java EE component and illustrates bestpractice design patterns for component interaction and client development. MedRecalso illustrates best practices for developing applications on WebLogic Server.The Spring version of MedRec, called MedRec-Spring is MedRec recast using theSpring Framework. If you are developing Spring applications on WebLogic Server, youshould review the MedRec-Spring sample application. In order to illustrate how Springcan take advantage of the enterprise features of WebLogic Server, MedRec wasrearchitected to replace core Java EE components with their Spring counterparts. Thefunctionality in the original version of MedRec is reimplemented using Spring inMedRec-Spring. Refer to the MedRec-Spring sample for details.To launch MedRec, run startWebLogic.cmd or script fromORACLE HOME/user projects/domains/medrec, where ORACLE HOME is the directoryyou specified as the Oracle Home when you installed Oracle WebLogic

WebLogic Monitoring Exporter1-7. WebLogic Logging Exporter1-7. WebLogic Server API Examples and Sample Application1-7. Upgrade1-8. System Administration. Overview of WebLogic Server System Administration2-1. Choosing the Appropriate Technology for Your Administrative Tasks2-1. Summary of