Introducing BEA WebLogic Server 7

BEA WebLogic Server 7 is the most widely adopted J2EE application server that is fully compliant with the industry-standard Java 2 Enterprise Edition version 1.3 platform, the programming model of choice for server-side development of enterprise-class applications.

WebLogic Server also implements the J2EE Connector Architecture (J2CA), which enables developers to connect Enterprise Information Systems (EISs) to the J2EE platform and to apply J2EE component models, transactions, and security infrastructures toward the integration of these systems. Table 9.1 shows the full list of J2EE application programming interfaces (APIs) and other leading Internet technology standards supported by WebLogic Server.

Table 9.1. J2EE 1.3 APIs and Other Leading Internet Technology Standards Supported by WebLogic Server

J2EE 1.3 APIs	Other Internet Technology Standards
EJB 2.0	HTTP 1.1
JDBC 2.0	SSLv3
J2CA 1.0	LDAPv2
JSP 1.2	X.509v3
Servlet 2.3	JAXP
JTA 1.0.1	SOAP 1.1 and 1.2
JMS 1.0.2	WSDL 1.1
JNDI 1.2	UDDI v2
Java RMI 1.0	SNMP 2.0
RMI/IIOP 1.0
JAAS 1.0
JMX 1.0
JavaMail 1.1
JAXP 1.1

Full compliance with the J2EE platform and the leading Internet standards ensures that applications built and deployed on WebLogic Server have the following capabilities:

• Are portable across a wide variety of hardware and operating systems and, therefore, are easier to integrate with applications running in heterogeneous environments, such as Unix, mainframe, and Windows. Heterogeneous environments are typical in most organizations.

• Can leverage a variety of best-of-breed third-party tools and components written to the J2EE APIs.

• Can integrate with prebuilt applications and components that conform to J2EE and the other technology standards described in Table 9.1.

Unlike the J2EE standard, however, an application server is a commercial software product that different vendors develop and sell. All application server vendors must make sure their products are certified and fully compliant with the J2EE platform (see Figure 9.4) by ensuring the following:

Figure 9.4. The J2EE platform specification.

• Developers are responsible for implementing the J2EE components (servlets, JSPs, and EJBs).

• Containers deliver the runtime environment, which encompasses access to the J2SE and J2EE APIs as well as remote communications services (such as RMI).

J2EE is to the application server what SQL is to the relational database management system (RDBMS). Does implementing SQL imply that an RDBMS product provides all the services and features required by today's enterprises ? It does not. Oracle, Sybase, Microsoft, and other leading database vendors use SQL to provide a common access language to their products only. Everything else, such as the reliability, availability, and scalability of their products, is designed and implemented based on their efforts to be competitively aligned with the features a high percentage of organizations (customers) are seeking from relational database management systems. By forecasting and successfully satisfying these customer feature requirements, these software vendors gain leadership and a competitive edge in their product space.

Likewise, the J2EE specification standardizes only the Java APIs (contracts) between components and the application server containers, and is nothing more than a definition of application infrastructure services. It is a common misconception to think that the J2EE specification covers all aspects of application infrastructure. It does not! For this reason, it is the responsibility of the application server vendors to implement the J2EE specification in an application infrastructure that also supports nonfunctional and Quality of Service (QoS) attributes, such as the following:

• Reliability ” Ensures that applications never "break," even under the most demanding circumstances.

• Availability ” Meets the accessibility requirements set forth by the service-level agreement of a business solution.

• Scalability ” Allows organizations to cost-effectively embrace any level of application usage, while maintaining a reasonable response time.

• Security ” Provides application- or component-level security mechanisms that can easily be leveraged across integrated business solutions to provide a unified security framework.

• Adaptability ” Provides the extensibility of a business solution.

• Compatibility ” Allows multiple hardware platforms and other infrastructure solutions to interoperate .

• Manageability ” Provides administration, change management control, and root cause diagnostics for business solutions.

• Reuseability ” Allows services to be leveraged across multiple business solutions.

The degree to which an application server satisfies these non-J2EE and QoS attributes is what distinguishes it as a market leader.