去除字符串中的空格、回车、换行符、制表符

private String replaceBlank(String str) {        String dest = "";        if (str!=null) {            Pattern p = Pattern.compile("\\s*|\t|\r|\n");            Matcher m = p.matcher(str);            dest = m.replaceAll("");        }        return dest;    }     public static void main(String[] args) {            System.out.println(Test.replaceBlank("  "                    + "     just do it!"));        }