How to read the first column of a CSV file

Question

Please help me to read the first column of the CSV file in Java. Here's my code:

public void fileload(String filename)throws IOException
{   int i=0;
    //Sorter S= new Sorter();
    File file=new File(filename); //Read File
    Scanner inputfile = new Scanner(file);
    while(inputfile.hasNext())   //Reading file content
    {
        orgarr[i]= inputfile.nextLine();
        System.out.println(orgarr[i]);
        i++;
    }

https://stackoverflow.com/questions/101100/csv-api-for-java?noredirect=1&lq=1 — Thilo, Oct 21 '18 at 11:23
I am reading a csv file with contents (2 columns only ): as "01L-900", "Ali" and have 107 records and task is to sort the first column contents. please help — Ali Asadullah Shah, Oct 21 '18 at 11:34

score 1 · Answer 1 · answered Oct 21 '18 at 11:25

You can use commons-csv that would take care of reading the format e.g. assuming CSVFormat.DEFAULT with optionally quoted text columns and comma as separator:

try (FileReader reader = new FileReader("your/path/to/file.csv")) {
  CSVParser parser = new CSVParser(reader, CSVFormat.DEFAULT);
  parser.getRecords().stream()
      .map(r -> r.get(0))
      .forEach(System.out::println);
}

The best solution would depend on your file format and size. Above is probably not suitable for huge CSV files as it loads all the records into memory with getRecords().

I am reading a csv file with contents (2 columns only ): as "01L-900", "Ali" and have 107 records and task is to sort the first column contents — Ali Asadullah Shah, Oct 21 '18 at 11:36

score 0 · Answer 2 · answered Jun 23 '19 at 18:26

Here I take the first column but I put a comma between the columns and when I fint that the number 10 is in the first column I print hello

File file = new File("src/test/resources/aaaa.csv");

        List<String> lines = Files.readAllLines(file.toPath(),
                StandardCharsets.UTF_8);
        lines.stream().forEach(l -> {
            String[] array =  l.split(",", 2);
            if(array[0].equals("10"))
                System.out.println("Hello");
        });

How to read the first column of a CSV file

2 Answers2