使用Eclipse和maven调用异步java servlet时出错

我正在使用Eclipse IDE来处理servlet . 我创建了一个maven项目来处理异步servlet 3.0并添加了适当的依赖项 . 代码 request.isAsyncSupported() 返回true . 现在，当我调用servlet时，它会给出这个错误

WARN：oejs.ServletHandler：/ testplugin / JsonServlet java.lang.IllegalStateException：DISPATCHED，初始于com.ajitpals.search.grid.fs的org.eclipse.jetty.server.Request.getAsyncContext（Request.java:325） . JsonServlet.doGet（JsonServlet.java:42）位于javax.servlet.http.HttpServlet.service（HttpServlet.java:734），位于org.eclipse.jetty的javax.servlet.http.HttpServlet.service（HttpServlet.java:847）位于org.eclipse.jetty.server.hand.handler.ScopedHandler.handle（ScopedHandler.java）的org.eclipse.jetty.servlet.ServletHandler.doHandle（ServletHandler.java:486）的.servlet.ServletHolder.handle（ServletHolder.java:594） ：119）org.eclipse.jetty上的org.eclipse.jetty.security.SecurityHandler.handle（SecurityHandler.java:524）或者org.eclipse.jetty上的org.eclipse.jetty.server.session.SessionHandler.doHandle（SessionHandler.java:233） . org.eclipse.jetty.server.SseionHandler.doScope（SessionHan dler.java:192）org.eclipse.jetty.server.handler.ContextHandler.doScope（ContextHandler.java:999）org.eclipse.jetty.server.handler.ScopedHandler.handle（ScopedHandler.java:117）at org位于org.eclipse.jetty.server.AbstractHttpConnection.handleRequest的org.eclipse.jetty.server.Server.handle（Server.java:351）的.eclipse.jetty.server.handler.HandlerWrapper.handle（HandlerWrapper.java:111） （AbstractHttpConnection.java:454）org.eclipse.jetty.server.AbstractHttpConnection.headerComplete（AbstractHttpConnection.java:890）org.eclipse.jetty.server.AbstractHttpConnection $ RequestHandler.headerComplete（AbstractHttpConnection.java:944）at org . eclipse.jetty.http.HttpParser.parseNext（HttpParser.java:634）org.eclipse.jetty.http.HttpParser.parseAvailable（HttpParser.java:230）org.eclipse.jetty.server.AsyncHttpConnection.handle（AsyncHttpConnection . java：77）atg.eclipse.jetty.io.nle.SelectChannelEndPoint.handle（SelectChannelEndPoint.java:609）org.eclipse.jetty.io.nio.SelectChannelEndPoint $ 1.r un（SelectChannelEndPoint.java:45）atg.eclipse.jetty.util.thread.QueuedThreadPool.runJob（QueuedThreadPool.java:599）org.eclipse.jetty.util.thread.QueuedThreadPool $ 3.run（QueuedThreadPool.java:534） ）在java.lang.Thread.run（未知来源） .

我在maven项目中添加了以下依赖项 .

<dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.1-b08</version>
</dependency>

<dependency>
    <groupId>org.eclipse.jetty</groupId>
    <artifactId>jetty-server</artifactId>
    <version>9.0.2.v20130417</version>
</dependency>

而servlet代码是

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

    if(request.isAsyncSupported()){

    final AsyncContext asynCtx = request.getAsyncContext();

    //Set the timeout
    asynCtx.setTimeout(35000);

    //Add the listeners.
    asynCtx.addListener(new AsyncListener() {

        public void onTimeout(AsyncEvent arg0) throws IOException {
            System.out.println("timeout");              
        }

        public void onStartAsync(AsyncEvent arg0) throws IOException {
            System.out.println("on start");             
        }

        public void onError(AsyncEvent arg0) throws IOException {
            System.err.println("on error");             
        }

        public void onComplete(AsyncEvent arg0) throws IOException {
            System.out.println("On complete");              
        }
    });

    //start the new thread.
    asynCtx.start(new Runnable() {

        public void run() {
            try{
                asynCtx.getResponse().getWriter().write(MessageFormat.format("<h1>Process task id : [{0}] and Name [{1}]</h1>", 
                        Thread.currentThread().getId()));
            }catch(Exception ex){
                System.err.println("async error " + ex.getMessage());
            }
        }
    });
    }
}

有没有人遇到类似的问题，我们如何解决它们 .

EDIT:

有时servlet也会出现以下错误

PWC6345: There is an error in invoking javac. A full JDK (not just JRE) is required Caused by:org.apache.jasper.JasperException:PWC6345: There is an error in invoking javac. A full JDK (not just JRE) is required

谢谢