java - 如何从 LinkedList 获取数据？

Question

这是我正在为我的程序寻找的示例输出。

示例输出

On each line enter a stadium name and the game revenue

Enter done when you are finished

Giants 1000

Foxboro 500

Giants 1500

done

Enter the name of a stadium to get the total revenue for:

Giants

The total revenue is 2500.00

除了最后的总收入，我的一切都正常了。我不确定如何进入我的链表并获取游戏收入并显示它。这是我现在的代码，以及我一直在搞乱的东西......

import java.util.LinkedList;
import java.util.Scanner;


public class LinkedLists {

    private final Scanner keyboard;



    private final LinkedList<String> stadiumNames;
    private final LinkedList<Integer> gameRevenue;


    public LinkedLists() {
        this.keyboard = new Scanner(System.in);
        this.stadiumNames = new LinkedList<String>();
        this.gameRevenue = new LinkedList<Integer>();
    }

    public void addData(String stadium, int revenue){
        stadiumNames.add(stadium);
        gameRevenue.add(revenue);
    }

    public void loadDataFromUser() {
        System.out.println("On each line enter the stadium name and game revenue.");
        System.out.println("Enter done when you are finished.");

        boolean done = false;
        while(!done) {
            System.out.print("Enter the name of the stadium:");
            String stadium = keyboard.next();
            if (stadium.equals("done")) {
                done = true;
            } else {
                System.out.print("Enter game revenue: ");
                addData(stadium, keyboard.nextInt());
            }
        }
    }

    // return -1 if not found
    public int getIndexForName(String name) {

        if(stadiumNames.contains(name)){
            System.out.println("The total revenue is: " +gameRevenue.get(0));
            System.exit(0);
        }

        return -1;

    }


    public void showInfoForName(String name) {
        int index = getIndexForName(name);
        if (index==-1) {
            System.out.println("There is no stadium named " + name);
        } else {

        }
    }

    public void showInfoForName() {
        System.out.println("Enter the name of the stadium to get the total revenue for it.");
        showInfoForName(keyboard.next());
    }

    public static void main(String[] args) {
        LinkedLists pgm = new LinkedLists();
        pgm.loadDataFromUser();
        pgm.showInfoForName();
    }
}

Answer 1

试试这个:

public int getIndexForName(String name) {
    if (stadiumNames.contains(name)) {
        int total = 0;
        for (int i = 0 ; i < stadiumNames.size() ; i++)
            if (stadiumNames.get(i).equals(name))
                total += gameRevenue.get(i);
        System.out.println("The total revenue is: " + total);
        System.exit(0);
    }
    return -1;
}

虽然有更好的方法可以做到这一点。我也许会使用 <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Map.html" rel="noreferrer noopener nofollow">Map</a>将每个体育场名称映射到其总收入。您可以在 addData 中更新此 map 方法。