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// Fails for supplementary or combining characters
public static String trim_bad1(String string) {
  char ch;
  for (int i = 0; i &lt;< string.length(); i += 1) {
    ch = string.charAt(i);
    if (!Character.isLetter(ch))
      break;
    }
  return string.substring(i);
}

// Fails for combining characters
public static String trim_bad2(String string) {
  int ch;
  for (int i = 0; i &lt;< string.length(); i += Character.charCount(ch)) {
    int ch = string.codePointAt(i);
    if (!Character.isLetter(ch))
      break;
    }
  return string.substring(i);
}

public static String trim_good(String string) {
  BreakIterator iter = BreakIterator.getCharacterInstance();
  iter.setText(string);
  for (int i = iter.first(); i != BreakIterator.DONE; i = iter.next()) {
    int ch = string.codePointAt(i);
    if (!Character.isLetter(ch)) {
      break;
    }
    
    if (i == BreakIterator.DONE) { // first or last text boundary has been reached
      return """";
    } else {
      return string.substring(i);
    }
  }
  return string;
}