Jakarta compatibility / Tomcat 10.x support

[f00dl3]

Tomcat 9 is probably going to become end of life in the near future at some point. Tomcat 10 requires using Jakarta instead of Java EE packages.

In version 2.6.0-rc1 it still appears that the classes are referencing the Java EE style of "extends Servlet"

Message Class [org.restlet.ext.servlet.ServerServlet] is not a Servlet

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

``
jakarta.servlet.ServletException: Class [org.restlet.ext.servlet.ServerServlet] is not a Servlet
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:597)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:673)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:340)
org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:391)
org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:896)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1744)
org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.base/java.lang.Thread.run(Thread.java:1583)

Root Cause

java.lang.ClassCastException: class org.restlet.ext.servlet.ServerServlet cannot be cast to class jakarta.servlet.Servlet (org.restlet.ext.servlet.ServerServlet is in unnamed module of loader org.apache.catalina.loader.ParallelWebappClassLoader @3abe3f9a; jakarta.servlet.Servlet is in unnamed module of loader java.net.URLClassLoader @3b95a09c)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:597)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:673)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:340)
org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:391)
org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)
org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:896)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1744)
org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)
org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.base/java.lang.Thread.run(Thread.java:1583)
``

[thboileau]

Hello @f00dl3 ,

I've play a little bit with tomcat, and cannot reproduce the issue. I attach a sample project that works for me.

Let me detail the steps I followed:

• I first installed tomcat 10.1.41: https://tomcat.apache.org/download-10.cgi
• then I generated a sample jakarta ee Maven project https://start.jakarta.ee/ with the following parameters:
  • Jakarta EE version: Jakarta EE 10
  • Jakarta EE profile: Web Profile
  • Java SE version: Java SE 17
  • Runtime: None
  • Docker support: No
• Once opened in Intellij, I've updated/added the following files:
  • pom.xml: added dependency to org.restlet:org.restlet.ext.servlet:2.6.0-rc1
  • added a org.eclipse.restlet.hello.MyServerResource and a org.eclipse.restlet.hello.MyApplication classes
  • web.xml: added configuration to reference the org.eclipse.restlet.hello.MyApplication class.
• I get this project: jakartaee10-web-jdk17.zip
• then I package the project: mvn clean package
• and deploy to tomcat: mv target/jakartaee10-web-jdk17.war /path/to/apache-tomcat-10.1.41/webapps
• the following resource is fine in browser: http://localhost:8080/jakartaee10-web-jdk17/1/hello