Introduction
There are a lot of changes and new features in Weblogic
Server 10.0. This new release gets better and efficient in terms of
performance, in terms of the supported APIs and in terms of the supported
external libraries. Almost all of the updates in the Java EE are reflected in
the WebLogic Server 10.0. In the following sections we will discuss 18 of these
new features:-
1) Core Server
1.1) Client Support and Modularity
In order to ensure for greater
flexibility some aspects of the file structure of WebLogic have reorganized. Now
many of components of the WebLogic Server that used to be in weblogic.jar are
now included in separate modules and weblogic.jar now refers to these
components in the modules directory from its manifest classpath. Now this file
has relative manifest classpath references to the WL_HOME/modules directory and
because of which it can not be moved to any new location. But if required three
options are available:-
- Include both weblogic.jar and WL_HOME/modules/weblogic.server.modules_10.0.0.0.jar directly in the classpath.
- Modify the manifest classpath of weblogic.jar to refer
to this JAR in the correct relative location.
- Create a consolidated wlfullclient.jar for client applications using the Jar Builder tool.
1.2) Subcomponents Version Information
There is a new verbose optional
argument in the java weblogic.version command. It returns version information
about many WebLogic Server components.
1.3) Security Consequences
The default J2SE security policy in
WebLogic server has been modified to grant access to the new modules. As a
result of the reorganization of the weblogic.jar, the security policy, in your
scenario, may need to be modified to grant access to the newer separate
modules.
2) Java EE Metadata Annotations and Dependency Injection
The Annotations feature in JDK 5.0 allows developers to
specify how the application component behaves in the container, requests for
Dependency Injections etc. in the Java class itself. This simplifies the
application development process and because of these features being useful for
EJBs, Web Services and Web Applications, annotations prove to be very handful for programmers in the
Java EE Programming model. Now application components can declare dependencies
on external resources and configuration parameters through annotations, which is called Dependency Injection. It becomes the duty of the
container to read those annotations and provide for the required resources.
3) Web Applications
Web Application technologies such as
JSPs and Servlets have new and changed features. These are discussed below:-
3.1) Support for Servlet 2.5
Keeping up the compliance with the
Java EE 5, WebLogic Server 10.0 implements the Servlet 2.5 specification. As
with the EJB 3.0 specification the support for annotations and Resource
Injections are among the new features of this release of the Servlets
Technology. The annotations are used to declare data in Java Code instead of
defining it in the long and confusing deployment descriptors. Web.xml is now
optional.
3.2) Support for JSP 2.1
Keeping up the compliance with the Java EE 5, WebLogic
Server 10.0 implements the JSP 2.1 specification. Among the new features of
this technology is the support for Deferred Expressions. This feature allows
deferring of evaluation of the expression so that it can be processed by the
underlying mechanism at a suitable time within its lifecycle. Annotations for
tag handlers and event listeners are other new
features in JSP 2.1.
3.3) Support for JSF 1.2 and JSTL 1.2
These packages come with WebLogic Server 10.0 in the form
of shared Web Application Libraries. Earlier versions like JSF 1.1 and JSTL 1.1, are still supported in WebLogic 10.0.
3.4) Annotations for Web Components in Weblogic format
There are certain WebLogic specific annotations for
Servlets and Filters. For Example, WLInitParam etc.
3.5) Java EE Application Client Utility
There is a new option available for
the weblogic.j2eeclient.Main utility. This
utility is used to execute Java EE application client code. The new option is
used to specify the name of the client Jar to be invoked when passing in an
exploded EAR file. For Example:-
java weblogic.j2eeclient.Main applicationclient.jar t3://localhost:7001
4) Support for the newer Enterprise JavaBeans, Version 3.0
WebLogic Server 10.0 implements the
Enterprise JavaBeans specification v3.0. Also it continues to support the
version 2.1 of the EJB Specification. So this means the applications written
in version 2.1 will continue to run on this newer Weblogic Server 10.0,
without any modification.
WebLogic also provides an implementation of the BEA, which means that JPA and JDO are also supported.
The EJB 3.0 is oriented towards
making it easier to program for the application developers. This is achieved by
reducing the number of programming artifacts and introducing annotations which
is related to the concept of Dependency Injections. Together these features in
EJB 3.0 make programming the bean file easier and more intuitive.
EJB 3.0 also looks after
standardizing the Persistence Framework and Object-Relational Mapping Model.
4.1) Upgrade EJB 2.x to EJB 3.0
Firstly, the default transaction
attribute in Session Beans and Message Driven Beans was "supports" in
version 2.1. But now it is changed to "required" in EJB 3.0. So do ensure to provide
proper transaction attribute while migrating to the newer version of EJBs.
Other than this there is no change for any of the three bean types in their
deployment in WebLogic 10.0.
5) Shared Library Support gets better
The Java EE supports use of optional
packages and shared libraries. An EAR file may have a directory that contains libraries
packaged in Jar files. The name of this directory is specified in the EAR
file's deployment descriptor "library-directory" element.
6) JDBC and JTA
A couple of features are introduced to the WebLogic JDBC and JTA in this release:-
6.1) Enhanced JDBC Connection Monitoring and Testing
WebLogic Server used to rely on JDBC
drivers to properly handle Database connection failures. For some network
failure conditions, WebLogic Server was not able to track a connection failure
until the TCP/IP expires from timeout. This feature provides additional
connection health monitoring and testing for connections when connectivity is
suspected to be broken.
6.2) Oracle Fast Connection Failover Support
Now WebLogic Server supports Oracle
Fast Connection Failover. This means now the JDBC applications can utilize a
driver independent way to use connection failover support from Oracle 10g.
6.3) Support for MySQL 5.0
WebLogic Server supports MySQL 5.0.x and bundles with the required drivers as well.
6.4) JTA 1.1 support
WebLogic Server is compliant with JTA
1.1. It includes support for looking up the TransactionSynchronizationRegistry
object in JNDI using java/TransactionSynchronizationRegistry.
BEA extends this support by providing two more global JNDI names: javax/transaction/TransactionSynchronizationRegistry and
weblogic/transaction/TransactionSynchronizationRegistry.
6.5) Migrating Transaction Recovery Service Automatically
Now an administrator can configure
the JTA Transaction Recovery Service, using the WebLogic Server migration
framework. This allows for automatic migration from the current unhealthy
hosting server to a healthy active server utilizing the WebLogic Server health
monitoring capabilities. So now a quick restart can be done on a redundant server
should the host server fails which in turn improves the availability of the JTA
TRS in a cluster.
6.6) Security for JTA across multiple Domains
WebLogic Server's JTA implementation supports the new Cross-Domain Security feature.
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