Question

问题：我正在尝试找到胜率（胜率百分比的公式为wins/(wins + loses)）。如何从胜利中获取值并输掉用户输入并将其添加到我的Sysout函数中。每次运行程序时都会显示：

East      W     L     PCT
Braves    45    66    0.000000
Cubs      87    77    0.000000

所以我要做的是获取实际值，而不是说“0.0000000”

public class Team {

    // Data fields...
    private int wins;
    private int loses;
    private String teamName;
    private String city;
    private String division;
    private double winPercentage;


    // Getters and setters...
    public int getWins() {
        return wins;
    }

    public void setWins(int wins) {
        this.wins = wins;
    }

    public int getLoses() {
        return loses;
    }

    public void setLoses(int loses) {
        this.loses = loses;
    }

    public String getTeamName() {
        return teamName;
    }

    public void setTeamName(String teamName) {
        this.teamName = teamName;
    }

    public String getCity() {
        return city;
    }

    public void setCity(String city) {
        this.city = city;
    }

    public String getDivision() {
        return division;
    }

    public void setDivision(String division) {
        this.division = division;
    }

    public double getWinPercentage() {
        return wins/(wins + loses);
    }

    public void setWinPercentage(double winPercentage) {
        this.winPercentage = winPercentage;
    }
}

public class PlayoffSelectorClass extends Team{

    public static void main(String[] args) {
        List<Team> teams  = new ArrayList<Team>();

        for (int i = 0; i < 6; i++) {

            Scanner input = new Scanner(System.in);

            System.out.println("Please enter team name: ");
            String name = input.nextLine();

            System.out.println("\nPlease enter the city " + name + " played in: ");
            String city = input.nextLine();

            System.out.println("\nPlease enter the division " + name + " play in: ");
            String division = input.nextLine();

            System.out.println("\nPlease enter the number of wins " + name + " has: ");
            Integer wins = input.nextInt();

            System.out.println("\nPlease enter the number of losses " + name + " has: ");
            Integer loses = input.nextInt();

            if (i < 5) {
                System.out.println("\nEnter your next team...\n");
            }

            Team team = new Team();
            team.setTeamName(name);
            team.setCity(city);
            team.setDivision(division);
            team.setWins(wins);
            team.setLoses(loses);
            team.setWinPercentage(wins / (wins + loses));

            teams.add(team);

        }

        System.out.println("East    W      L      PCT\n");

        for (Team team : teams) {
            System.out.printf("%s\t%s\t%s\t%f\n",team.getTeamName() + "    ", team.getWins() + "   " , team.getLoses(), team.getWinPercentage());
        }

    }
}

Answer 1

问题在于：

public double getWinPercentage() {
    return wins/(wins + loses);
}

您正在进行整数除法，即仅保留结果的int部分，并将其隐式地转换为double。例如，如果：

wins = 10;
loses = 20;

然后winPercentage == 10/30 == 0.33..，您只保留0并将其转换为double。因此，0.0000...等
你可以做的是：

public double getWinPercentage() {
    return wins/(double) (wins + loses);
}

显示来自getter方法的信息有问题

1 个答案: