if (regEx == null) throw new IllegalArgumentException("No regular expression."); pattern = RegExFactory.createCaseInsensitivePattern(regEx);
if (pattern == null) throw new IllegalArgumentException("No pattern."); this.pattern = pattern;
    FindRegExVisitor(HiViewer viewer, String regEx)    {        super(viewer);        if (regEx == null)            throw new IllegalArgumentException("No regular expression.");        pattern = RegExFactory.createCaseInsensitivePattern(regEx);        foundNodes = new HashSet();    }