Book Image

Getting Started with Oracle WebLogic Server 12c: Developer's Guide

Book Image

Getting Started with Oracle WebLogic Server 12c: Developer's Guide

Overview of this book

Oracle WebLogic server has long been the most important, and most innovative, application server on the market. The updates in the 12c release have seen changes to the Java EE runtime and JDK version, providing developers and administrators more powerful and feature-packed functionalities. Getting Started with Oracle WebLogic Server 12c: Developer's Guide provides a practical, hands-on, introduction to the application server, helping beginners and intermediate users alike get up to speed with Java EE development, using the Oracle application server. Starting with an overview of the new features of JDK 7 and Java EE 6, Getting Started with Oracle WebLogic Server 12c quickly moves on to showing you how to set up a WebLogic development environment, by creating a domain and setting it up to deploy the application. Once set up, we then explain how to use the key components of WebLogic Server, showing you how to apply them using a sample application that is continually developed throughout the chapters. On the way, we'll also be exploring Java EE 6 features such as context injection, persistence layer and transactions. After the application has been built, you will then learn how to tune its performance with some expert WebLogic Server tips.
Table of Contents (18 chapters)
Getting Started with Oracle WebLogic Server 12c: Developer's Guide
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Introducing Oracle WebLogic Server 12c


In a very brief history of WebLogic, we must remember that it came to Oracle through the acquisition of BEA (Bill, Edward, Alfred). Although the name WebLogic is widely associated with BEA, they didn't create the product.

In fact, WebLogic itself was a company formed in 1995 (same year as BEA) that created a middle-tier server to enhance communication between applets and servers providing implementations for SNMP, JDBC drivers, and ping. This server was named Tengah but also had a codename, T3Server (the three-tier server) and used a custom proprietary network protocol called T3. This server later evolved to be a Java application server as we know today and right after BEA acquired WebLogic (the company) in 1998, Tengah was officially renamed to WebLogic (Version 4.5). Later, BEA acquired a high performance JVM (BEA JRockit, now Oracle JRockit) that was certified against WebLogic and received various performance awards.

The last BEA release of WebLogic Server was Version 10.0, a full Java EE 5 application server.

WebLogic Server @ Oracle

After BEA's acquisition in 2008, Oracle announced WebLogic as the strategic application server to replace Oracle Application Server (OC4J), and it also became the foundation for Oracle Fusion Middleware and Oracle Fusion Applications, the main families of Oracle products.

The first release under Oracle's brand was WebLogic Server 10gR3 (10.3.0), soon followed by Version 11g. Here's a figure showing all 11g and 12c releases till now:

The focus of this book is WebLogic Sever 12c, which is approximately the eighth release by Oracle and has lots of new and improved features, as shown in the next section.

Most relevant features

Here is a list of the most important features of Oracle WebLogic Server 12c Version 12.1.2, the most current version and the focus of this book:

  • Full Java EE 6 support: WebLogic 12c is the first release to implement Java EE 6 specification, delivering all its features. The next section of this chapter is going to explain new and relevant additions to Java EE 6.

  • Certified with JDK 6 and JDK 7: Through the use of JDK 7, developers can leverage all language optimizations available in the new version of the JDK, including features already converged from JRockit—the proprietary JDK that came from BEA.

  • JDBC Store for JTA logs: WebLogic supports JDBC Store to persist transaction logs (TLOGs) in a database, and leverages replication and high availability on the underlying database. It also simplifies disaster recovery since the synchronization happens at the database level.

  • Built-in Classloader Analysis Tool (CAT): WebLogic CAT is a web-based application that can filter the different classloaders available (JVM, application server, applications) showing the classes loaded by each one of them. This functionality enables the analysis of common classloader issues such as conflicts. The tool even offers suggestions on how to fix problems.

  • Coherence 12.1.2: This release includes support for Coherence Servers Management through WebLogic Management Framework, including security and application deployment through GAR (Grid Archive) files. It offers asynchronous backup, multiple Coherence REST applications, integration with Oracle Universal Installer, and support for ECID (Execution Context ID) for correlation with Oracle Fusion Middleware. Other than these, it still offers WebLogic integration for HTTP session management (Coherence*Web) and Oracle TopLink Grid as a JPA mechanism.

  • Glassfish to WebLogic deployment descriptor support: WebLogic offers support for Glassfish deployment descriptors so you can seamlessly deploy web applications written for Glassfish Server on WebLogic Server.

  • Enhanced WebLogic Maven support: In this release, one of the most important changes is that it's not required to generate the WebLogic Maven plugin anymore; there is now a bundled version under /wlserver/server/lib/. Also, several new tasks were added to the plugin, including support for server installation from zip files, domain creation, start/stop servers, and execution of inline WLST scripts.

  • WebSockets support: The newest release 12.1.2, brings support for the WebSocket protocol, which provides two-way and full-duplex communication over a single TCP connection between clients and the server. With this, we can open a direct connection between a browser and the server, receiving and sending information in an asynchronous way, opening possibilities to create Rich Internet Applications (RIA).

  • OSGi bundles: The OSGi architecture is now available as a WebLogic feature, providing us a way to create a set of configurations to define our own modules and use its API to, for instance, start and stop modules and acquire data sources. The implementation that comes with WebLogic Server is Apache Felix 4.0.3.

  • Server templates and dynamic servers/clusters: To make Oracle's Cloud Application Foundation more flexible, Version 12.1.2 of WebLogic Server introduced these concepts that basically give us an easy way to scale up a WebLogic domain. Up to this version, we had to manually create and configure managed servers to distribute workload; now, we create a server template once, setting up a few basic points of information such as name prefix, and create a dynamic cluster based on this template. When the workload reaches a peak, we just instruct the environment to fire up additional servers based on these configurations, and it's done. It's quick and easy.

  • Dynamic clustered JMS Servers: Another improvement that involves ease of configuration when dealing with dynamic clusters is that now a JMS Server—the component used to deploy JMS resources such as queues and topics to a server—can be targeted to a WebLogic cluster. Previous versions only accepted a managed server as a target for such components, and now management and migration tasks are a lot easier to perform.