我正在尝试使用servlet连接kafkaproducer，并在eclipse中设置我的项目。但当我运行kafkaproducer时，我得到了一个例外：
org.apache.catalina.core.standardwrappervalve invoke severe:servlet[simple\u kafka.simpleproducer]的servlet.service（），路径为[/kafka\u web]引发异常[servlet execution引发异常]，根本原因为java.lang.classnotfoundexception:org.apache.kafka.clients.producer.kafkaproducerorg.apache.catalina.loader.webappclassloaderbase.loadeclass（webappclassloaderbase。java:1291)在org.apache.catalina.loader.webappclassloaderbase.loadeclass（webappclassloaderbase。java:1119)在simple\u kafka.simpleproducer.dopost（simpleproducer。java:56)在javax.servlet.http.httpservlet.service（httpservlet。java:661)在javax.servlet.http.httpservlet.service（httpservlet）。java:742)位于org.apache.catalina.core.applicationfilterchain.internaldofilter（applicationfilterchain）。java:231)在org.apache.catalina.core.applicationfilterchain.dofilter（applicationfilterchain。java:166)在org.apache.tomcat.websocket.server.wsfilter.dofilter（wsfilter。java:52)在org.apache.catalina.core.applicationfilterchain.internaldofilter（applicationfilterchain）。java:193)在org.apache.catalina.core.applicationfilterchain.dofilter（applicationfilterchain。java:166)在org.apache.catalina.core.standardwrappervalve.invoke（standardwrappervalve。java:199)在org.apache.catalina.core.standardcontextvalve.invoke（standardcontextvalve。java:96)在org.apache.catalina.authenticator.authenticatorbase.invoke（authenticatorbase。java:478)在org.apache.catalina.core.standardhostvalve.invoke（standardhostvalve。java:140)在org.apache.catalina.valves.errorreportvalve.invoke（errorreportvalve。java:81)在org.apache.catalina.valves.abstractaccesslogvalve.invoke（abstractaccesslogvalve。java:650)在org.apache.catalina.core.standardenginevalve.invoke（standardenginevalve。java:87)在org.apache.catalina.connector.coyoteadapter.service（coyoteadapter。java:342)在org.apache.coyote.http11.http11processor.service（http11processor。java:803)在org.apache.coyote.abstractprocessorlight.process（abstractprocessorlight。java:66)在org.apache.coyote.abstractprotocol$connectionhandler.process（abstractprotocol。java:868)位于org.apache.tomcat.util.net.nioendpoint$socketprocessor.dorun（nioendpoint）。java:1459)在org.apache.tomcat.util.net.socketprocessorbase.run（socketprocessorbase。java:49)在java.util.concurrent.threadpoolexecutor.runworker（threadpoolexecutor。java:1149)在java.util.concurrent.threadpoolexecutor$worker.run（threadpoolexecutor。java:624)在org.apache.tomcat.util.threads.taskthread$wrappingrunnable.run（taskthread。java:61)在java.lang.thread.run（线程。java:748)
我的kafkaproducerservlet如下：

package simple_kafka;

import java.io.IOException;
import java.util.Properties;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerConfig;
//import org.apache.kafka.clients.producer.Producer;
import org.apache.kafka.clients.producer.ProducerRecord;

/**
 * Servlet implementation class SimpleProducer
 */
@WebServlet("/producer")
public class SimpleProducer extends HttpServlet {
    private static final long serialVersionUID = 1L;

    /**
     * @see HttpServlet#HttpServlet()
     */
    public SimpleProducer() {
        super();
        // TODO Auto-generated constructor stub
    }

    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
//      response.getWriter().append("Served at: ").append(request.getContextPath());
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
        response.getWriter().append("Served at: ").append(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG);
        String topicName = "ReplicaTopic";
          String key = "Key1";
          String value = "Value-1";

          Properties props = new Properties();
          props.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "192.168.1.59:9092,192.168.1.59:9093");
          props.put("key.serializer","org.apache.kafka.common.serialization.StringSerializer");         
          props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");

          KafkaProducer<String, String> producer = new KafkaProducer <String, String>(props);
          try {
              ProducerRecord<String, String> record = new ProducerRecord<>(topicName,key,value);
              producer.send(record);           
              producer.close();
          }
          catch(Exception e) {
              response.getWriter().append("Exception at: ").append((CharSequence) e);
          }
//        response.sendRedirect("/consumer");
    }
}

我在项目属性的buildpath中包含了以下jar：
Kafka2.12-0.11.0.1.jar
Kafka客户端-0.11.0.1.jar
slf4j-api-1.7.25.jar