How to read text file in Java and store it to an array?

To read a file to an array, add all lines to a List via BufferedReader.readLine, then convert it to an array with toArray.

Here's how you do it:

// [file.txt]
// item one
// item two
// item three

BufferedReader reader = new BufferedReader(new FileReader(new File("/Users/xero/file.txt")));
List<String> items = new ArrayList<>();

try (reader) {
  String line;

  while ((line = reader.readLine()) != null) {
    items.add(line);
  }
} catch (IOException e) {
  throw new RuntimeException(e);
}

String[] itemsInArray = items.toArray(new String[]{});
System.out.println(Arrays.toString(itemsInArray)); // [item one, item two, item three]

What if my delimiter is not a new line?

You can use Scanner instead of BufferedReader:

// [file.txt]
// item one ; item two ; item three

Scanner scanner = new Scanner(new File("/Users/xero/file.txt")).useDelimiter(" ; ");
List<String> items = new ArrayList<>();

try (scanner) {
  while (scanner.hasNext()) {
    items.add(scanner.next());
  }
}

String[] itemsInArray = items.toArray(new String[]{});
System.out.println(Arrays.toString(itemsInArray)); // [item one, item two, item three]