Chapter 3. Creating XML rules

Use the <javaclass> element to find imports, methods, variable declarations, annotations, class implementations, and other items related to Java classes. For a better understanding of the <javaclass> condition, see the JavaDoc for the JavaClass class.

The following is an example of a rule that tests for WebLogic-specific Apache XML packages:

<rule id="weblogic-03000">
    <when>
        <javaclass references="weblogic.apache.xml.{*}" />
    </when>
    <perform>
        <hint title="WebLogic Specific Apache XML Package" effort="1" category-id="mandatory">
            <message>
                Code using this package should be replaced with code using the org.apache.xml package from [Apache
                Xerces](http://xerces.apache.org/).
            </message>
        </hint>
    </perform>
</rule>

Use the <xmlfile> element to find information in XML files. For a better understanding of the <xmlfile> condition, see the JavaDoc for the XmlFile class.

The following is an example of a rule that tests for an XML file:

<rule id="<UNIQUE_RULE_ID>">
    <when>
        <xmlfile matches="/w:web-app/w:resource-ref/w:res-auth[text() = 'Container']">
            <namespace prefix="w" uri="http://java.sun.com/xml/ns/javaee"/>
        </xmlfile>
    </when>
    <perform>
        <hint title="Title for Hint from XML">
            <message>Container Auth</message>
        </hint>
        <xslt description="Example XSLT Conversion" extension="-converted-example.xml"
              template="/exampleconversion.xsl"/>
    </perform>
</rule>

Use the <project> element to query the Maven POM file for the project characteristics. For a better understanding of the <project> condition, see the JavaDoc for the Project class.

The following is an example of a rule that checks for a JUnit dependency version between 2.0.0.Final and 2.2.0.Final.

<rule id="UNIQUE_RULE_ID">
    <when>
        <project>
            <artifact groupId="junit" artifactId="junit" fromVersion="2.0.0.Final" toVersion="2.2.0.Final"/>
        </project>
    </when>
    <perform>
        <lineitem message="The project uses junit with the version between 2.0.0.Final and 2.2.0.Final"/>
    </perform>
</rule>

Use the <filecontent> element to find strings or text within files, for example, a line in a Properties file. For a better understanding of the <filecontent> condition, see the JavaDoc for the FileContent class.

Use the <file> element to find the existence of files with a specific name, for example, an ibm-webservices-ext.xmi file. For a better understanding of the <file> condition, see the JavaDoc for the File class.

Use the <has-hint> element to test whether a file or line has a hint already associated with it. It is primarily used to prevent firing if a hint already exists, or to implement rules for default execution when no other conditions apply. For a better understanding of the <has-hint> condition, see the JavaDoc for the HasHint class.

The following is an example of a rule that checks to see if a hint exists for an IBM JMS destination message, and if not, includes it.

<rule id="websphere-jms-eap7-03000">
  <when>
    <javaclass references="{package}.{prefix}{type}Message" />
  </when>
  <perform>
    <iteration>
      <when>
        <not>
          <has-hint />
        </not>
      </when>
      <perform>
        <hint title="IBM JMS destination message" effort="1" category-id="mandatory">
          <message>
            JMS `{package}.{prefix}{type}Message` messages represent the actual data passed through JMS destinations. This reference should be
            replaced with the Java EE standard API `javax.jms.{type}Message`.
          </message>
          <link href="https://docs.oracle.com/javaee/7/tutorial/jms-concepts003.htm#sthref2271" title="Java EE 7 JMS Tutorial - Message API" />
          <tag>jms</tag>
          <tag>websphere</tag>
        </hint>
      </perform>
    </iteration>
  </perform>
  <where param="type">
    <matches pattern="(Text|Stream|Object|Map|Bytes)?" />
  </where>
  <where param="prefix">
    <matches pattern="(JMS|MQe|MQ)" />
  </where>
  <where param="package">
    <matches pattern="com.ibm(\..*)?\.jms" />
  </where>
</rule>

The <has-hint> element is used to determine if a hint exists for a file or line. It does not have any child elements.

Use the <has-classification> element to test whether a file or line has a classification. It is primarily used to prevent firing if a classification already exists, or to implement rules for default execution when no other conditions apply. For a better understanding of the <has-classification> condition, see the JavaDoc for the HasClassification class.

The has-classification element is used to determine if a specified classification exists. It does not have any child elements.

Use the <graph-query> element to search the generated graph for any elements. This element is primarily used to search for specific archives. For a better understanding of the <graph-query> condition, see the JavaDoc for the QueryHandler class.

The following is an example of a rule that tests to determine if any ehcache packages are found.

<rule id="embedded-cache-libraries-01000">
    <when>
        <graph-query discriminator="JarArchiveModel">
            <property name="fileName" searchType="regex">.*ehcache.*\.jar$</property>
        </graph-query>
    </when>
    <perform>
        <classification title="Caching - Ehcache embedded library" category-id="cloud-mandatory" effort="5">
            <description>
                The application embeds an Ehcache library.

                Cloud readiness issue as potential state information that is not persisted to a backing service.
            </description>
        </classification>
        <technology-tag level="INFORMATIONAL">Ehcache (embedded)</technology-tag>
    </perform>
</rule>

Use the <dependency> element to search dependencies defined within the application’s POM file to determine whether they are supported by the target runtime.

The following is an example of a rule that checks for all artifacts belonging to the org.springframework.boot group that have a version up to, and including, 1.6.0.

<rule id="springboot-00001">
    <!-- rule condition, when it could be fired -->
    <when>
        <dependency groupId="org.springframework.boot" artifactId="{*}" toVersion="1.6.0" />
    </when>
    <!-- rule operation, what to do if it is fired -->
    <perform>
        <hint title="Unsupported version of Spring Boot" effort="3" category-id="mandatory">
            <message>Spring Boot has to be updated to Spring Boot 2.0 before being able to be migrated to a version supported by Red Hat Runtimes</message>
            <link href="https://access.redhat.com/articles/3349341" title="RHOAR Spring Boot Supported Configurations" />
            <link href="https://access.redhat.com/articles/3348731" title="RHOAR Component Details Overview" />
            <link href="https://github.com/spring-projects/spring-boot/wiki/Spring-Boot-2.0-Migration-Guide" title="Spring Boot 2.0 Migration Guide" />
        </hint>
    </perform>
</rule>

The <classification> element is used to identify or classify application resources that match the rule. It provides a title that is displayed in the report, a level of effort, and it can also provide links to additional information about how to migrate this resource classification. For a better understanding of the <classification> action, see the JavaDoc for the Classification class.

The following is an example of a rule that classifies a resource as a WebLogic EAR application deployment descriptor file.

<rule id="XmlWebLogicRules_10vvyf">
    <when>
        <xmlfile as="default" matches="/*[local-name()='weblogic-application']"></xmlfile>
    </when>
    <perform>
        <iteration>
            <classification title="Weblogic EAR Application Descriptor" effort="3"/>
        </iteration>
    </perform>
</rule>

The <link> element is used in classifications or hints to provide links to informational content. For a better understanding of the <link> action, see the JavaDoc for the Link class.

The following is an example of a rule that creates links to additional information.

<rule id="SeamToCDIRules_2fmb">
    <when>
        <javaclass references="org.jboss.seam.{*}" as="default"/>
    </when>
    <perform>
        <iteration>
            <classification title="SEAM Component" effort="1">
                <link href="http://www.seamframework.org/Seam3/Seam2ToSeam3MigrationNotes" title="Seam 2 to Seam 3 Migration Notes"/>
                <link href="http://docs.jboss.org/weld/reference/latest/en-US/html/example.html" title="JSF Web Application Example"/>
                <link href="http://docs.jboss.org/weld/reference/latest/en-US/html/contexts.html" title="JBoss Context Documentation"/>
                <link href="http://www.andygibson.net/blog/tutorial/cdi-conversations-part-2/" title="CDI Conversations Blog Post"/>
            </classification>
        </iteration>
    </perform>
</rule>

The <hint> element is used to provide a hint or inline information about how to migrate a section of code. For a better understanding of the <hint> action, see the JavaDoc for the Hint class.

The following is an example of a rule that creates a hint.

<rule id="WebLogicWebServiceRules_8jyqn">
    <when>
        <javaclass references="weblogic.wsee.connection.transport.http.HttpTransportInfo.setUsername({*})" as="default">
            <location>METHOD</location>
        </javaclass>
    </when>
    <perform>
        <iteration>
            <hint title="Proprietary web-service" category-id="mandatory" effort="3">
                <message>Replace proprietary web-service authentication with JAX-WS standards.</message>
                <link href="http://java-x.blogspot.com/2009/03/invoking-web-services-through-proxy.html" title="JAX-WS Proxy Password Example"/>
            </hint>
        </iteration>
    </perform>
</rule>

The <xslt> element specifies how to transform an XML file. For a better understanding of the <xslt> action, see the JavaDoc for the XSLTTransformation class.

The following is an example of rule that defines an XSLT action.

<rule id="XmlWebLogicRules_6bcvk">
    <when>
        <xmlfile as="default" matches="/weblogic-ejb-jar"/>
    </when>
    <perform>
        <iteration>
            <classification title="Weblogic EJB XML" effort="3"/>
            <xslt title="JBoss EJB Descriptor (Windup-Generated)" template="transformations/xslt/weblogic-ejb-to-jboss.xsl" extension="-jboss.xml"/>
        </iteration>
    </perform>
</rule>

The <lineitem> element is used to provide general migration requirements for the application, such as the need to replace deprecated libraries or the need to resolve potential class loading issues. This information is displayed on the project or application overview page. For a better understanding of the <lineitem> action, see the JavaDoc for the LineItem class.

The following is an example of a rule that creates a lineitem message.

<rule id="weblogic_servlet_annotation_1000">
    <when>
        <javaclass references="weblogic.servlet.annotation.WLServlet" as="default">
            <location>ANNOTATION</location>
        </javaclass>
    </when>
    <perform>
        <hint effort="1">
            <message>Replace the proprietary WebLogic @WLServlet annotation with the Java EE 6 standard @WebServlet annotation.</message>
            <link href="https://access.redhat.com/articles/1249423" title="Migrate WebLogic Proprietary Servlet Annotations" />
            <lineitem message="Proprietary WebLogic @WLServlet annotation found in file."/>
        </hint>
    </perform>
</rule>

The <iteration> element specifies to iterate over an implicit or explicit variable defined within the rule. For a better understanding of the <iteration> action, see the JavaDoc for the Iteration class.

The following is an example of a rule that performs an iteration.

<rule id="jboss-eap5-xml-19000">
    <when>
        <xmlfile as="jboss-app" matches="/jboss-app"/>
        <xmlfile as="jboss-app-no-DTD" matches="/jboss-app" public-id=""/>
    </when>
    <perform>
        <iteration over="jboss-app">
            <classification title="JBoss application Descriptor" effort="5"/>
        </iteration>
        <iteration over="jboss-app-no-DTD">
            <classification title="JBoss application descriptor with missing DTD" effort="5"/>
        </iteration>
        <iteration over="jboss-app-no-DTD">
            <xslt title="JBoss application descriptor - JBoss 5 (Windup-generated)" template="transformations/xslt/jboss-app-to-jboss5.xsl" extension="-jboss5.xml"/>
        </iteration>
    </perform>
</rule>