public static String tokensToString(Word [] tokens) {
StringBuilder sb = new StringBuilder(512);
for(int i = 0; i < tokens.length; i ++){
if(i > 0) sb.append(" ");
Word l = tokens[i];
sb.append(l.word() + "{" + l.beginPosition() + ", " + l.endPosition() + "}");
}
return sb.toString();
}
// /**