如何使用扫描仪从 java 中的文本文件中读取列？-解网

问：

我有这个文本，我想从我的名为 Data.txt 的项目中阅读第一列。

//column names:   productId, name,numInStock,provider,pricePerUnit

private static String records =     "231A,Light Bulb,123,Wilco,1.75:"+
                                "113D,Hairbrush,19,Aamco,3.75:"+
                                "521W,Shampoo,24,Acme,6.95:"+
                                "440Q,Dishwashing Detergent,20,Wilco,1.75:"+
                                "009G,Toothbrush,77,Wilco,0.85:"+
                                "336C,Comb,34,Wilco,0.99:"+
                                "523E,Paper Pad Set,109,Congdon and Chrome,2.45:"+
                                "888A,Fake Diamond Ring,111,Americus Diamond,3.95:"+
                                "176A,Romance Nove1 1,20,Barnes and Noble,3.50:"+
                                "176B,Romance Nove1 2,20,Barnes and Noble,3.50:"+
                                "176C,Romance Nove1 3,20,Barnes and Noble,3.50:"+
                                "500D,Floss,44,Wilco,1.25:"+
                                "135B,Ant Farm,5,Wilco,8.00:"+
                                "211Q,Bicycle,9,Schwinn,75.95:"+
                                "932V,Pen Set,50,Congdon and Chrome,9.95:"+
                                "678Q,Pencil 50,123,Congdon and Chrome,9.95:"+
                                "239A,Colored Pencils,25,Congdon and Chrome,4.75:"+
                                "975B,Shower Curtain,25,Wilco,6.50:"+
                                "870K,Dog Bowl,15,Wilco,4.75:"+
                                "231S,Cat Bowl,15,Wilco,4.75:"+
                                "562M,Kitty Litter,15,Wilco,3.25:"+
                                "777X,Dog Bone,15,Wilco,4.15:"+
                                "933W,Cat Toy,15,Wilco,2.35:"+
                                "215A,Hair Ball,0,Little Jimmy,0.00:";

我写了这段代码来这样做，但我没有得到所需的输出。我的代码是

public static void main(String[] args) {
    // TODO Auto-generated method stub
    try {
        Scanner input = new Scanner(System.in);

        File file = new File("C:\\Users\\student\\Desktop\\workspace\\Welcome\\src\\Data.txt");
        input = new Scanner(file);

        while (input.hasNextLine()) {
            String line = input.nextLine();
            String[] words = line.split(",");
            System.out.println(words[0]);
            input.useDelimiter(",");
        }
        input.close();

    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

我想以这种格式获取输出

这是我得到的输出，我想删除说私有静态字符串记录 = 的部分，以及“.

//column names:   productId

private static String records =     "231A
                                "113D
                                "521W
                                "440Q
                                "009G
                                "336C
                                "231S

java io java.util.scanner

          Scanner in = new Scanner(str) ;
      in.useDelimiter(":") ;
      ArrayList<String> al = new ArrayList<>() ;
      while( in.hasNext())
      {
          al.add(in.next() ) ;
      }
      
      for( int i = 0 ; i < al.size(); ++i )
      {
          String s = al.get(i) ;
          String[] s2 = s.split(",") ;
          System.out.println( s2[0] );
      }

如何使用扫描仪从 java 中的文本文件中读取列？

How to read a column from a text file in java using scanner?

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