如何使用扫描仪的分隔符方法

Question

我目前正在执行游戏风险。在我的Board课程中，我阅读了三个不同的文本文件，其中包括国家、大陆及其邻近地区。当我构建一个新大陆时，它的构造器需要以下内容（字符串名、int-bonusArmies、ArrayList-memberCountries）。现在，我用扫描器从一个文本文件中读取，这个文件是这样组织的，它的名字，它拥有的奖金军队，每行的其余部分是它的成员国。

北美、5、阿拉斯加、阿尔伯塔省、中美洲、美国东部、格陵兰岛、西北地区、安大略省、魁北克省、美国西部、南美、2、阿根廷、巴西、委内瑞拉欧洲、5、英国、冰岛、北欧、斯堪的纳维亚、南欧、乌克兰、西欧非洲、3、刚果、东非、埃及、马达加斯加、北非、，南非、亚洲、7、阿富汗、中国、印度、伊尔库茨克、日本、堪察加半岛、中东、蒙古、暹罗、西伯利亚、乌拉尔、雅库茨克澳大利亚、2、澳大利亚东部、印度尼西亚、洛特、新几内亚、西澳大利亚

我知道我需要为扫描器设置一个分隔符，我已经尝试了多种方法，但都没有用。下面是我尝试创建大陆hashmap的一个示例。

public void createContinents()
{   

    Scanner inputTwo = new Scanner( new File( "continents.txt");

while( inputTwo.hasNext())  //continues to create and add countries until their are none next
{   
    String line = inputTwo.nextLine();  //stores the entire line
    Scanner lineScan = new Scanner( line);  //passes the entire line into Scanner
    lineScan.useDelimiter(","); //sets the Scanner's delimiter pattern

    String name = inputTwo.next();  //stores the first String which is the name of the current continent being created
    System.out.println( " the name is" + name);

    int bonusArmies = inputTwo.nextInt();   //stores the second String which is casted into an int for the continent bonus armies
    System.out.println(" the number of bonus armies is" + bonusArmies);

    ArrayList<Country> memberCountries = new ArrayList<Country>();  //creates an arraylist to hold the member countries of current continent

    while( inputTwo.hasNext())  //goes through the rest of the line to add the member countries until it reaches the end of the line
    {   

        memberCountries.add( countries.get(inputTwo.next()));//gets string name of country and pass it as key to store into temp arraylist of countries         
        System.out.println( "the member countries" + memberCountries);
    }

        continent = new Continent( name,  bonusArmies,  memberCountries);   //creates continent
        continents.put(name , continent);   //associates a key to the current continent

}


    inputTwo.close();

 }    

这是图像中的文本。

    PS C:\Users\repti_000\desktop\risk\homeworks2120\game> java BoardTester
     the name is
    SouthAmerica,2,Argentina,Brazil,Venezuela 

    Exception in thread "main" java.util.InputMismatchException
    at java.util.Scanner.throwFor(Unknown Source)
    at java.util.Scanner.next(Unknown Source)
    at java.util.Scanner.nextInt(Unknown Source)
    at java.util.Scanner.nextInt(Unknown Source)
    at Board.createContinents(Board.java:66)
    at Board.loadBoard(Board.java:141)
    at Board.<init>(Board.java:27)
    at BoardTester.main(BoardTester.java:7)
   PS C:\Users\repti_000\desktop\risk\homeworks2120\game>

Answer 1

您从inputTwo而不是lineScan获取数据。您应该在这里考虑更清晰的名称，这使得检测这类问题更加简单。而不是输入两个地图数据或世界扫描仪，而不是lineScan可能大陆数据。

Answer 2

为了更清楚，我重新命名了扫描器和一些变量，并添加了一些注释。我想知道为什么你的hashmap大陆看起来像大陆（名字，大陆），而你的存储是大陆的名字（就像你用构造函数给它的那样）。使用大陆。getName（）似乎是一种更好的做法。

正如罗顿爵士指出的，你用错了扫描仪，你的名字确实不清楚。试着让你的变量名更清晰一点，这应该有助于时间。

    public void createContinents()  { 

    //  Scan the continents.txt file
    Scanner worldScan = new Scanner( new File( "continents.txt");

    //  While worldScan has a next line, run loop
    //  CHANGED: not hasNext(), but hasNextLine()
    while( worldScan.hasNextLine()) {

        //  Create a scanner for the selected line in worldScan
        String continentLine = inputTwo.nextLine();
        Scanner continentScan = new Scanner(continentLine);
        continentScan.useDelimiter(",");

        //  Grab the continent from the scanner
        String name = continentScan.next();
        System.out.println( " the continent name is" + name);

        //  Grab the armies from the scanner
        //  CHANGED: you read it out as a string, not as an int
        int bonusArmies = Integer.toString(continentScan.next());
        System.out.println(" the number of bonus armies is" + bonusArmies);

        //  Instantiate loop variable countries
        ArrayList<Country> memberCountries = new ArrayList<Country>();

        while( continentScan.hasNext()) {
            memberCountries.add(countries.get(continentScan.next()));
            System.out.println( "the member countries" + memberCountries);
        }

        //  Instantiate loop variable continent
        Continent continent = new Continent( name,  bonusArmies,  memberCountries);

        //  Add continent to the hashmap
        continents.put(name,continent);

        continentScan.close();
    }

    worldScan.close();
 }