Check out example codes for "reading in lines from a file java". It will help you in understanding the concepts better.

Code Example 1

private ArrayList<String> readFileLines(String filepath) throws FileNotFoundException, IOException{
  File fp = new File(filepath);
  FileReader fr = new FileReader(fp);
  BufferedReader br = new BufferedReader(fr);

  ArrayList<String> lines = new ArrayList<>();
  String line;
  while((line = br.readLine()) != null) { lines.add(line); }

  fr.close();
  return lines;
}

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