Abbreviate a String using ellipses in both sides in Java

// w  w w. ja v a 2s. c  o m
public class Main {
  public static void main(String[] argv) {
    System.out.println(abbreviate("this is a test from java2s.com", 13));
    System.out.println(abbreviate("this is a test from java2s.com", 13, 4));
  }

  public static String abbreviate(String str, int maxWidth) {
    return abbreviate(str, 0, maxWidth);
  }

  public static String abbreviate(String str, int offset, int maxWidth) {
    if (str == null) {
      return null;
    }
    if (maxWidth < 4) {
      throw new IllegalArgumentException(
          "Minimum abbreviation width is 4");
    }
    if (str.length() <= maxWidth) {
      return str;
    }
    if (offset > str.length()) {
      offset = str.length();
    }
    if ((str.length() - offset) < (maxWidth - 3)) {
      offset = str.length() - (maxWidth - 3);
    }
    if (offset <= 4) {
      return str.substring(0, maxWidth - 3) + "...";
    }
    if (maxWidth < 7) {
      throw new IllegalArgumentException(
          "Minimum abbreviation width with offset is 7");
    }
    if ((offset + (maxWidth - 3)) < str.length()) {
      return "..." + abbreviate(str.substring(offset), maxWidth - 3);
    }
    return "..." + str.substring(str.length() - (maxWidth - 3));
  }
}