问当联系RMI服务器时客户端线程失败: java.rmi.UnmarshalException:错误解组返回

EN

java.rmi.UnmarshalException: error unmarshalling return; nested exception is: 
    java.lang.ClassNotFoundException: servertest.DictionaryInterface (no security manager: RMI class loader disabled)
    at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
    at java.rmi.Naming.lookup(Unknown Source)
    at Client.LookupWorker.run(LookupWorker.java:27)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: servertest.DictionaryInterface (no security manager: RMI class loader disabled)
    at sun.rmi.server.LoaderHandler.loadProxyClass(Unknown Source)Thread didnt finish its job properly, error: java.lang.NullPointerException

if (request.getParameter("word") != null) {
            String word = request.getParameter("word");
            String res;
            System.out.println("The word to find: "+word);

            // Get handle on our pool
            WorkerPool pool = WorkerPool.getInstance( );
            // Create Job
            LookupWorker wordWork = new LookupWorker(word);
            // Add job to pool
            res = pool.addJob(wordWork);
            request.getSession().setAttribute("result", res);
            response.sendRedirect("/SearchResults"); 
        }

package Client;

import java.net.MalformedURLException;
import java.rmi.Naming;
import java.rmi.NotBoundException;
import java.rmi.RemoteException;

import DictionaryInterface.DictionaryInterface;

public class LookupWorker implements WorkerPlan {

    private String word;
    private String jobName;
    private String serverResult;
    private long threadId;

    public LookupWorker(String w) {
        super();
        this.word = w;
        jobName = "Lookup Job";
    }

    @Override
    public void run(){
        DictionaryInterface Dictonary = null;
        try {
            Dictonary = (DictionaryInterface) Naming.lookup("rmi://127.0.0.1:1099/DictionaryService");
        } catch (MalformedURLException | RemoteException | NotBoundException e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
        try {
            serverResult = Dictonary.lookup(word);
        } catch (RemoteException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
            System.out.println(serverResult); 
            threadId = Thread.currentThread().getId();
    }

    public String getServerResult() {
        return serverResult;
    }

    public String getWord() {
        return word;
    }

    public String getJobName() {
        return jobName;
    }

    @Override
    public String toString() {
        return jobName + " [Id= " + threadId + "word= " + word + ", serverResult= " + serverResult + "]";
    }   

}

public String addJob(WorkerPlan job) {
        String result;
        threadCounter++;
        // Adding new lookup job to our queue
        System.out.println("Adding a " + job.getJobName() + " to the queue. Searching for: " + job.getWord() + " Job number: " + threadCounter);
        executor.execute(job);
        try {
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } // sleep so we can wait for rmi object to come in
        System.out.println(job.toString());
        result = job.getServerResult();
        return result;
    }