public @NotNull String dumpState() {
    @NonNls StringBuilder result = new StringBuilder();
    result.append("intervals:\n");
    int lineCount = getLineCount();
    for (int line = 0; line < lineCount; line++) {
      result.append(line).append(": ").append(getLineStartOffset(line)).append("-").append(getLineEndOffset(line)).append(", ");
    }
    if (lineCount > 0) {
      result.setLength(result.length() - 2);
    }
    return result.toString();
  }
public @NotNull String dumpState()