如何从一个 class 获取一个字符串到另一个

Question

I'm making an air traffic control system and I have a class Plane where a name is called depending on if there is a plane coming. If there is 1 plane then it says KLM if there's none then it says that there is no plane.

I am looking for a way to get this plane name from the plane class to the airport class to put into a queue. This is the code for the plane class

package airtrafficcontrolv3;

import java.util.TimerTask;


class Plane
        extends TimerTask
{

    public int nextPlaneLoop = 0;
    public int planes;
    public int fuel;
    public String planeName;

    @Override
    public void run()
    {
        Observer o = new ObserverImpl();
        Subject s = new SubjectImpl();

        if (nextPlaneLoop <= 167)
        {
            //Currently only running 1 or 0 planes...
            planes = (int) (Math.random() * ((2 - 1) + 1));
            //System.out.println("Random generated plane amount: " + planes);
            //System.out.println("Method called, one whole day loop");
            //Adds to the plane in the airspace loop
            nextPlaneLoop++;
            //System.out.println("Loop incrementing: " + nextPlaneLoop);

            if (planes == 0)
            {
                //System.out.println("No fuel is required as no planes are coming in");
                planeName = "No incoming plane";
                //System.out.println("Planes name is: " + planeName);

                System.out.println("Inbound amount of planes: "+planes);
                System.out.println("Inbound: " + planeName);
                System.out.println("Inbound fuel amount: None ");

                System.out.println(" ");
            }
            else
            {
                //Amount of fuel
                fuel = 30 + (int) (Math.random() * ((120 - 30) + 1));
                //System.out.println("Random fuel: " + fuel);
                planeName = "KLM AirFrance";
                System.out.println("Inbound amount of planes: "+planes);
                System.out.println("Inbound: " + planeName);
                System.out.println("Inbound fuel amount: "+fuel);

                System.out.println(" ");
            }
        }
        else
        {
            this.cancel();
            System.out.println("Day Finished");
        }

                s.addObserver(o);
                s.setState(planeName);

                System.out.println(planeName);

                //finalName = planeName;
                Airport point = new Airport();

                //System.out.println(planeName);
    }
}

This is what is in my airport class.

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package airtrafficcontrolv3;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;

public class Airport
{
    Plane point = new Plane();
    Queue <String> waiting = new LinkedList<String>();

    public Airport()
    {
        //waiting.add(point.);

        while (!waiting.isEmpty())
        {
            System.out.println("Waiting to take off: "+waiting);
            try
            {
                System.out.println("Preparing to taxi: "+waiting.remove());
                Thread.sleep(5000);
            }
            catch (InterruptedException ex)
            {
                Logger.getLogger(Airport.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
    }

}

Is it possible that anyone can suggest how to get the name from the plane class to the airport class please.

Answer 1

Create an accessor for planeName in the class Plane ( getName() is a common style nomenclature). Call it from your Airport class per instance of Plane .

Answer 2

wouldn't it just be point.planeName You have a member that is a Plan in your airport class call point. Not sure exactly what your are asking...

Answer 3

Make a getter like

public String getName() {
    return planeName;
}

or just access it through

point.planeName

Which would also work but would be considered bad style.

Answer 4

The getter implementations won't work here, since the code in Plane is running asynchronously. To get the Observer pattern to work here, Plane needs to wrap an instance of Observable. Then at some point, an Airport (which needs to implement Observer) instance needs to be registered with that Observable.