Ошибка java/lang/NoClassDefFoundError

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 * and open the template in the editor.
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package pac;
//import com.AgentClass2;
import java.io.IOException;
import javax.bluetooth.DeviceClass;
import javax.bluetooth.DiscoveryListener;
import javax.bluetooth.RemoteDevice;
import javax.bluetooth.ServiceRecord;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Form;
import javax.microedition.midlet.*;
 
/**
 * @author Admin
 */
public class Midlet31Class extends MIDlet {
    private AgentClass  agent;
    public Midlet31Class(){
        Display display = Display.getDisplay(this);
        Form mainForm = new Form("My Form");
        display.setCurrent(mainForm);
    }
    public void startApp() {
       // agent = this.getClass(AgentClass);
      agent = new AgentClass();
      agent.start();
 
    }
 
    public void pauseApp() {
    }
 
    public void destroyApp(boolean unconditional) {
        notifyDestroyed();
    }
 
public static class AgentClass4 extends Thread implements DiscoveryListener{
    public AgentClass4() {
 
 
        }
 
    public void deviceDiscovered(RemoteDevice arg0, DeviceClass arg1) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
    public void inquiryCompleted(int arg0) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
    public void serviceSearchCompleted(int arg0, int arg1) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
    public void servicesDiscovered(int arg0, ServiceRecord[] arg1) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
}
}

/*
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package pac;
 
import javax.bluetooth.DeviceClass;
import javax.bluetooth.DiscoveryListener;
import javax.bluetooth.RemoteDevice;
import javax.bluetooth.ServiceRecord;
 
/**
 *
 * @author Admin
 */
public class AgentClass extends Thread implements DiscoveryListener {
 
    public AgentClass(){
        
    }
    public void deviceDiscovered(RemoteDevice arg0, DeviceClass arg1) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
    public void inquiryCompleted(int arg0) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
    public void serviceSearchCompleted(int arg0, int arg1) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
    public void servicesDiscovered(int arg0, ServiceRecord[] arg1) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
 
}