无法计算getTotalFlightTime（）

Question

Itinerary类存储有关具有以下成员的旅程的信息：

•一个名为flights的私有ArrayList数据字段，其中包含按DepartureTime递增顺序排列的旅程航班。（提示：您不需要进行排序。）

•使用ArrayList类型的指定航班创建旅程的构造函数。

•名为getTotalFlightTime（）的方法，以分钟为单位返回旅程的总飞行时间。（提示：为每个飞行对象调用getFlightTime（）方法。）

•一个名为getTotalTravelTime（）的方法，它返回行程中从第一个航班的起飞时间到最后一个航班的到达时间的总旅行时间（以分钟为单位）。假设所有时间都在同一时区。

package que6;

/**
 *
 * @author vpi764
 */


import java.util.ArrayList;
import java.util.GregorianCalendar;
public class TestFlightItinerary {


    public static void main(String[] args) {

  lic static void main(String[] args) {
        ArrayList<Flight>flights = new ArrayList<>();
  Flight F1 =  new Flight("US230", new GregorianCalendar(2014, 5, 5, 5, 5, 0), new GregorianCalendar(2014, 5, 5, 6, 15, 0));
    Flight F2 =  new Flight("US235", new GregorianCalendar(2014, 5, 5, 6, 55, 0), new GregorianCalendar(2014, 5, 5, 7, 45, 0));
      Flight F3 =  new Flight("US237", new GregorianCalendar(2014, 5, 5, 9, 35, 0), new GregorianCalendar(2014, 5, 5, 12, 55, 0));

      flights.add(F1);
      flights.add(F2);
      flights.add(F3);

 }

}

class Flight{

        private String flightNo;
        private GregorianCalendar departureTime;
        private GregorianCalendar arrivalTime;


        //Constructor
        Flight(String SpecNo,GregorianCalendar SpecDtime ,GregorianCalendar SpecAtime ){
            this.flightNo = SpecNo;
            this.departureTime = SpecDtime;
            this.arrivalTime = SpecAtime;
        }
        //Getters
        public String GetFlightNo() {
            return flightNo;
        }
        public GregorianCalendar GetDtime() {
            return departureTime;
        }
        public GregorianCalendar GetAtime() {
            return arrivalTime;
        }

        //setters
        // If we don't use setter the could would still work because we are getting input in constructor with parameters
        public void SetFlightNo(String Number) {
            flightNo = Number;
        }
        public void SetDtime(GregorianCalendar Dtime) {
            departureTime = Dtime;
        }
        public void SetAtime(GregorianCalendar Atime) {
            arrivalTime = Atime;
        }

        public long getTimeinMillis() {
                return (arrivalTime.getTimeInMillis() - departureTime.getTimeInMillis());
                }
                // getFlightTime method
                public long getFlightTime() {
                return getTimeinMillis() / (60 * 1000);
                }
    }

class Itinerary {


    ArrayList<Flight> flights = new ArrayList<>();

   public Itinerary(){
           this.flights = flights;
    }
    public long getTotalFlightTime(ArrayList<Flight> flights){

    }
    public long getTotalTravelTime(){

    }


}

Answer 1

如果我正确理解了这些说明，您就不需要对ArrayList进行排序。您需要做的只是定义一个接受航班数组列表的构造函数。

您的行程等级应为：

class Itinerary {
    ArrayList<Flight> flights; // no need to instantiate, flights passed in as arg

    public Itinerary(ArrayList<Flight> flights) {
        this.flights = flights;
    }

    public long getTotalFlightTime(){
        // Do stuff
    }
    public long getTotalTravelTime(){
        // Do Stuff
    }
}

然后在您的main方法中添加以下内容：

ArrayList<Flight> flights = new ArrayList<>();
flights.addAll(F1, F2, F3);
Itinerary myItinerary = new Itinerary(flights);