Improve toString() in SegmentInfo

// TODO: we could append toString of attributes() here?

public String toString(int delCount) {
  StringBuilder s = new StringBuilder();
  s.append(name).append('(').append(version == null ? "?" : version).append(')').append(':');
  char cfs = getUseCompoundFile() ? 'c' : 'C';
  s.append(cfs);

  s.append(maxDoc);

  if (delCount != 0) {
    s.append('/').append(delCount);
  }

  if (indexSort != null) {
    s.append(":[indexSort=");
    s.append(indexSort);
    s.append(']');
  }

  // New Code
  if (!diagnostics.isEmpty()) {
    s.append(":[diagnostics=");
    for (Map.Entry<String, String> entry : diagnostics.entrySet())
      s.append("<").append(entry.getKey()).append(",").append(entry.getValue()).append(">,");
    s.setLength(s.length() - 1);
    s.append(']');
  }

  // New Code
  if (!attributes.isEmpty()) {
    s.append(":[attributes=");
    for (Map.Entry<String, String> entry : attributes.entrySet())
      s.append("<").append(entry.getKey()).append(",").append(entry.getValue()).append(">,");
    s.setLength(s.length() - 1);
    s.append(']');
  }

  return s.toString();
}