Upgrading jboss server 4.0 with jdk6 to wildfly15 with jdk8

Question

previously my project was on jdk 6 with jboss 4.i upgraded from jdk6 to jdk8 . When i was using jdk 8 with jboss4 it was working properly but after upgrading jboss 4 with wildfly 15 i am getting below error. in web.xml i configured crystalReportViewer as given below .wildfly 15 is giving error but when i removed the crystalReportConfiguration line then its working properly..

enter code here

 <context-param>
    <param-name>crystal_image_uri</param-name>
    <param-value>crystalreportviewers</param-value>
   </context-param>

   <context-param>
        <param-name>crystal_image_use_relative</param-name>
        <param-value>webapp</param-value>
    </context-param>
    <servlet>
        <servlet-name>CrystalReportViewerServlet</servlet-name>
        <servlet-class>com.crystaldecisions.report.web.viewer.CrystalReportViewerServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>CrystalReportViewerServlet</servlet-name>
        <url-pattern>/CrystalReportViewerHandler</url-pattern>
    </servlet-mapping>

Caused by: org.jboss.as.server.deployment.DeploymentUnitProcessingException: java.lang.ClassNotFoundException: com.crystaldecisions.report.web.viewer.CrystalReportViewerServlet from [Module "deployment.ubarms.war" from Service Module Loader] at org.jboss.as.jaxrs.deployment.JaxrsScanningProcessor.checkDeclaredApplicationClassAsServlet(JaxrsScanningProcessor.java:437) at org.jboss.as.jaxrs.deployment.JaxrsScanningProcessor.scanWebDeployment(JaxrsScanningProcessor.java:278) at org.jboss.as.jaxrs.deployment.JaxrsScanningProcessor.deploy(JaxrsScanningProcessor.java:109) at org.jboss.as.server.deployment.DeploymentUnitPhaseService.start(DeploymentUnitPhaseService.java:144) ... 8 more