Migrating from WebSphere Application Server Community Edition to WebSphere Application Server

132 Migrating from WebSphere Application Server Community Edition to WebSphere Application Server

 Another common error is caused by Apache Xalan and Xerces, which are

usually bundled with application servers.

 JDom is also bundled with WebSphere Application Server V6.

5.1.3 Deployment Descriptors

The J2EE specification does not cover all the aspects of application deployment

and configuration. This is why we have vendor-specific Deployment Descriptors.

Table 5-1 on page 133 lists both the J2EE and vendor-specific Deployment

Descriptors. Each application server uses a different set of files because they are

implemented differently and have different feature sets.

The biggest issues associated with Deployment Descriptors while migrating to

WebSphere Application Server V6 can be summarized include:

 CMP to database schema mapping

WebSphere Application Server V6.1 uses a completely different way of

mapping CMPs to the database schema, compared to the other application

servers covered in this book. The only way of creating these files is by using

either Rational Application Developer V7.0 or the Java Application

Verification Kit.

 The J2EE standard Deployment Descriptors are mapped to the WebSphere

Application Server V6.1 specific Deployment Descriptors with IDs, as

illustrated in Example 5-1 on page 133 and Example 5-2 on page 133. This

means that the ID in the WebSphere Application Server V6.1 specific

Deployment Descriptor must match the one in the J2EE standard Deployment

Descriptor.

 WebSphere Application Server V6.1 validates the Deployment Descriptors

more strictly than other application server. This will lead to the following

problems when migrating:

– Deployment Descriptors will fail validation because the elements are not in

the proper order or the DTD is incorrect.

– JSPs will not compile.

Chapter 5. Common migration issues 133

Example 5-1 shows how the standard J2EE ejb-jar.xml Deployment Descriptor

and WebSphere Application Server V6.1 are mapped with IDs.

Example 5-1 Excerpt from ejb-jar.xml

...

<resource-ref id="ResourceRef_1173653784123">

<res-ref-name>jms/activity/QueueConnectionFactory</res-ref-name>

<res-type>javax.jms.QueueConnectionFactory</res-type>

<res-auth>Container</res-auth>

<res-sharing-scope>Shareable</res-sharing-scope>

</resource-ref>

...

In Example 5-2, a resource reference with the ID ResourceRef_1173653784123

is mapped to a JNDI name pointing to a resource that is managed by WebSphere

Application Server V6.1.

Example 5-2 Excerpt from ibm-ejb-jar-bnd.xmi

...

<resRefBindings xmi:id="ResourceRefBinding_1173653784123"

jndiName="jms/activity/QueueConnectionFactory">

<bindingResourceRef

href="META-INF/ejb-jar.xml#ResourceRef_1173653784123"/>

</resRefBindings>

...

Table 5-1 lists the J2EE standard and vendor-specific Deployment Descriptors.

Table 5-1 J2EE and vendor-specific Deployment Descriptors and configuration files

Description J2EE

specification

WebSphere Application Server V6 WebSphere Application

Server Community

Edition

EAR

application

application.xml ibm-application-bnd.xmi

ibm-application-ext.xmi

geronimo-application.xml

WAR

application

web.xml ibm-web-bnd.xmi

ibm-web-ext.xmi

geronimo-web.xml

EJB

application

ejb-jar.xml ibm-ejb-jar-bnd.xmi

ibm-ejb-jar-ext.xmi

ibm-ejb-access-bean.xml

openejb-jar.xml

J2EE client

application

application-clie

nt.xml

ibm-application-client-bnd.xmi

ibm-application-client-ext.xmi

geronimo-application-clien

t.xml