我一直在徒劳地尝试实现 tomcat 9 的 jakarta servlet，而不是以前的 javax.servlet 实现（因为我的理解是 jakarta 包是前进的方向）。问题是，当我将浏览器指向我的 servlet 的 url 时，我收到以下错误...
java.lang.ClassCastException: class cti.nm.web.Index cannot be cast to class javax.servlet.Servlet (cti.nm.web.Index is in unnamed module of loader org.apache.catalina.loader.ParallelWebappClassLoader @48c76607; javax.servlet.Servlet is in unnamed module of loader java.net.URLClassLoader @621be5d1)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
org.apache.coyote.ajp.AjpProcessor.service(AjpProcessor.java:432)
org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:888)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1597)
org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130)
java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.base/java.lang.Thread.run(Thread.java:832)
问题已经很明显了。Tomcat 正在尝试将我的 jakarta.servlet.http.HttpServlet 转换为 javax.servlet.Servlet，这显然不起作用。我无法想象的是如何告诉它 servlet 实际实现的类。
类本身被声明为...
package cti.nm.web;
import jakarta.servlet.http.HttpServlet;
import java.io.IOException;
import java.io.PrintWriter;
import jakarta.servlet.ServletException;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
public class Index extends …什么可能导致此错误？
Caused by: jakarta.servlet.UnavailableException: Servlet class org.restlet.ext.servlet.ServerServlet is not a jakarta.servlet.Servlet
at org.eclipse.jetty.servlet.ServletHolder.checkServletType (ServletHolder.java:499)
at org.eclipse.jetty.servlet.ServletHolder.doStart (ServletHolder.java:377)
at org.eclipse.jetty.util.component.AbstractLifeCycle.start (AbstractLifeCycle.java:96)
at org.eclipse.jetty.servlet.ServletHandler.lambda$initialize$2 (ServletHandler.java:699)
at java.util.stream.SortedOps$SizedRefSortingSink.end (SortedOps.java:357)
at java.util.stream.AbstractPipeline.copyInto (AbstractPipeline.java:485)
at java.util.stream.AbstractPipeline.wrapAndCopyInto (AbstractPipeline.java:474)
at java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining (StreamSpliterators.java:312)
at java.util.stream.Streams$ConcatSpliterator.forEachRemaining (Streams.java:735)
at java.util.stream.ReferencePipeline$Head.forEach (ReferencePipeline.java:658)
at org.eclipse.jetty.servlet.ServletHandler.initialize(ServletHandler.java:724)
我正在从mvn jetty:run插件运行网络应用程序