count numbers in given text code example

Example: program code for counting the similarwrod in the sentences

public static int count(String word) {
    if (word == null || word.isEmpty()) {
      return 0;
    }

    int wordCount = 0;

    boolean isWord = false;
    int endOfLine = word.length() - 1;
    char[] characters = word.toCharArray();

    for (int i = 0; i < characters.length; i++) {

      // if the char is a letter, word = true.
      if (Character.isLetter(characters[i]) && i != endOfLine) {
        isWord = true;

        // if char isn't a letter and there have been letters before,
        // counter goes up.
      } else if (!Character.isLetter(characters[i]) && isWord) {
        wordCount++;
        isWord = false;

        // last word of String; if it doesn't end with a non letter, it
        // wouldn't count without this.
      } else if (Character.isLetter(characters[i]) && i == endOfLine) {
        wordCount++;
      }
    }

    return wordCount;
  }