java - 我无法弄清楚为什么我的数组列表没有使用我所说的新值进行更新

Question

如果我在问这个问题时犯了任何错误，请告诉我我知道这是一个专业论坛，这是我的第一篇文章。因此，我正在尝试为我的 APCS 高中课程编写代码，但是遇到了问题。仅供参考，这里是我遇到问题的部分代码的说明 -

3.) 创建一个名为 updateLocation 的方法，将国家添加到运行的城市（例如伦敦，英格兰）。打印列表。

我遇到的问题发生在第 3 步中。我已经编写了 updateLocation 方法并为该方法编写了 if 循环，以用 Country 替换已定义的位置，但是，它没有正确输出。

这是我的代码-

import java.util.ArrayList;


public class Runner {
    private double time;
    private String atheleteName;
    private String nationality;
    private String date;
    private String location;

    public Runner(double time, String atheleteName, String nationality, String date, String location) {
        this.time = time;
        this.atheleteName = atheleteName;
        this.nationality = nationality;
        this.date = date;
        this.location = location;
    }

    public double getTime() {
        return time;
    }

    public String getAtheleteName() {
        return atheleteName;
    }

    public String getNationality() {
        return nationality;
    }

    public String getDate() {
        return date;
    }

    public String getLocation() {
        return location;
    }

    public void setTime(double time) {
        this.time = time;
    }

    public void setAtheleteName(String atheleteName) {
        this.atheleteName = atheleteName;
    }

    public void setNationality(String nationality) {
        this.nationality = nationality;
    }

    public void setDate(String date) {
        this.date = date;
    }

    public void setLocation(String location) {
        this.location = location;
    }

    public String toString() {
        return  
        time + atheleteName + nationality + date + location;

    }

    public static void main(String[] args) {

        ArrayList<Runner> runners = new ArrayList<>();

        runners.add(new Runner(     9.58,"         Usain Bolt   ","     Jamaica   ","   16 August 2009   ","      Berlin   "));
        runners.add(new Runner(     9.69,"         Tyson Gray   ","     USA   ","       20 September 2009   ","   Shanghai   "));
        runners.add(new Runner(     9.69,"         Yohan Blake   ","    Jamaica   ","   23 August 2012   ","      Lausanne"));
        runners.add(new Runner(     9.72,"         Asafa Powell   ","   Jamaica   ","   02 September 2008   ","   Lausanne   "));
        runners.add(new Runner(     9.78,"         Nesta Carter   ","   Jamaica   ","   29 August 2010   ","      Rieti   "));
        runners.add(new Runner(     9.79,"         Maurice Greene   "," USA   ","       16 June 1999   ","        Athens   "));
        runners.add(new Runner(     9.79,"         Justin Gatlin   ","  USA   ","       05 August 2012   ","      London   "));
        runners.add(new Runner(     9.80,"          Steve Mullings   "," Jamaica   ","   04 June 2011   ","        Eugene   "));
        runners.add(new Runner( 9.84,"         Donovan Bailey   "," Canada   ","    27 July 1996   ","        Atlanta   "));
        runners.add(new Runner(9.84,"         Bruny Surin   ","    Canada   ","    22 August 1999   ","      Seville   "));
        System.out.println("\nOriginal Array- ");
        System.out.println("");
        System.out.println("Time(sec):      Name:        Nationality:      Date:              Location:");
        System.out.println("---------------------------------------------------------------------------");
        printRunners(runners);
        updateLocation(runners);
        System.out.println("\nUpdate Runners- ");
        System.out.println("");
        System.out.println("Time(sec):      Name:        Nationality:      Date:              Location:");
        System.out.println("---------------------------------------------------------------------------");
        printRunners(runners);
        insertName(runners,10.49,"   Florence (G.) Joyner   ","USA   ","       06 July 1988   ","        Indianapolis, Indiana   ");
        System.out.println("\nUpdate Runners- ");
        System.out.println("");
        System.out.println("Time(sec):      Name:        Nationality:      Date:              Location:");
        System.out.println("---------------------------------------------------------------------------");
        printRunners(runners);
        replaceName(runners,"         Bruny Surin   ","         Carl Lewis   ",   9.86   ,"     USA   ","       23 August 1991   ","      Tokyo, Japan   ");
        System.out.println("\nUpdate Runners- ");
        System.out.println("");
        System.out.println("Time(sec):      Name:        Nationality:      Date:              Location:");
        System.out.println("---------------------------------------------------------------------------");
        printRunners(runners);

    }

    public static void printRunners(ArrayList<Runner> runners){
        for(Runner runner:runners)
            System.out.println(runner);
    } 

    public static void updateLocation(ArrayList<Runner> runners){
        for(Runner runner : runners){
            if(runner.getLocation().equalsIgnoreCase("Berlin")){
                runner.setLocation("Berlin, Germany");
            }else if(runner.getLocation().equalsIgnoreCase("Shanghai")){
                runner.setLocation("Shanghai, China");
            }else if(runner.getLocation().equalsIgnoreCase("London")){
                runner.setLocation("London, England");
            }else if(runner.getLocation().equalsIgnoreCase("Athens")){
                runner.setLocation("Athens, Greece");
            } else if(runner.getLocation().equalsIgnoreCase("Eugene")){
                runner.setLocation("Eugene, South Africa");
            } else if(runner.getLocation().equalsIgnoreCase("Seville")){
                runner.setLocation("Seville, France");
            }else if(runner.getLocation().equalsIgnoreCase("Lausanne")){
                runner.setLocation("Lausanne, Spain");
            }else if(runner.getLocation().equalsIgnoreCase("Rieti")){
                runner.setLocation("Rieti, Australia");
            }else if(runner.getLocation().equalsIgnoreCase("Atlanta")){
                runner.setLocation("Atlanta, USA");
            }
        }
    }

    public static void insertName(ArrayList<Runner> runners, double time, String atheleteName, String nationality, String date, String location){
        Runner runner = new Runner(time,atheleteName,nationality,date,location);
        runners.add(runner);
    }

    public static void replaceName(ArrayList<Runner> runners, String searchName, String replaceName, double time, String nationality, String date, String location){
        for(Runner runner: runners){
            if(runner.getAtheleteName().equalsIgnoreCase(searchName)){
                runner.setTime(time);
                runner.setAtheleteName(replaceName);
                runner.setNationality(nationality);
                runner.setDate(date);
                runner.setLocation(location);
            }
        }
    }

}

我希望我的结果是——

时间（秒）： 姓名： 国籍： 日期： 地点：

9.58 Usain Bolt 牙买加 2009 年 8 月 16 日，德国柏林

9.69 Tyson Gray 美国 2009 年 9 月 20 日 中国上海

9.69 Yohan Blake 牙买加 2012 年 8 月 23 日 西班牙洛桑

9.72 Asafa Powell 牙买加 2008 年 9 月 2 日 西班牙洛桑

9.78 Nesta Carter 牙买加 2010 年 8 月 29 日 Rieti，澳大利亚

9.79 Maurice Greene 美国 1999 年 6 月 16 日，希腊雅典

9.79 Justin Gatlin 美国 2012 年 8 月 5 日 英国伦敦

9.8 Steve Mullings 牙买加 2011 年 6 月 4 日 南非尤金

9.84 Donovan Bailey 加拿大 1996 年 7 月 27 日 美国亚特兰大

9.84 Bruny Surin 加拿大 1999 年 8 月 22 日 法国塞维利亚
................................... ...................................但是，我的输出看起来像这样-

时间（秒）： 姓名： 国籍： 日期： 地点：

9.58 Usain Bolt 牙买加 2009 年 8 月 16 日柏林

9.69 Tyson Gray 美国 2009 年 9 月 20 日 上海

9.69 Yohan Blake 牙买加 2012 年 8 月 23 日 洛桑

9.72 Asafa Powell 牙买加 2008 年 9 月 2 日 洛桑

9.78 Nesta Carter 牙买加 2010 年 8 月 29 日 Rieti

9.79 Maurice Greene 美国 1999 年 6 月 16 日，雅典

9.79 Justin Gatlin 美国 2012 年 8 月 5 日 伦敦

9.8 Steve Mullings 牙买加 2011 年 6 月 4 日尤金

9.84 Donovan Bailey 加拿大 1996 年 7 月 27 日亚特兰大

9.84 Bruny Surin 加拿大 1999 年 8 月 22 日 塞维利亚

如果您对代码有任何疑问，请告诉我。

标签： javaarraylist

Answer 1

字符串" Berlin "和"Berlin" 不相等（即使您忽略大小写比较它们。第一个包含前导和尾随空格。删除它们或替换runner.getLocation()为runner.getLocation().trim().