Display in a JSF page properties from MANIFEST.MF using spring framework

In a recent project we wanted to show the Hudson build info in the footer of the template.

So we configured the maven pom to execute the

            <plugin>
                <groupid>org.apache.maven.plugins</groupid>
                <artifactid>maven-war-plugin</artifactid>
                <version>2.0.2</version>
                <configuration>
                    <manifest>
                        <adddefaultimplementationentries>true</adddefaultimplementationentries>
                    </manifest>
                    <archive>
                        <manifestentries>
                            <specification-title>${project.name}</Specification-Title>
                            <specification-version>${project.version}</Specification-Version>
                            <implementation-version>${BUILD_TAG}</Implementation-Version>
                            <build-final-name>${project.build.finalName}</build-final-name>
                        </manifestentries>
                    </archive>
                </configuration>
            </plugin>

to ensure the data is saved inside the META-INF/MANIFEST.MF.

To show the data in the screen we relied upon the InputStreamPropertyEditor of the Spring framework defining a bean

            <bean id="manifestFile" class="java.util.jar.Manifest">
                        <constructor-arg value="/META-INF/MANIFEST.MF" type="java.io.InputStream"/>
            </bean>

and in the footer part of the facelets template we simply wrote:

           hudson build tag: #{manifestFile.mainAttributes.getValue('implementation-version')}

Note: we used jboss-EL that allows evaluation of method calls.