[Spring Boot] java.lang.NoClassDefFoundError: org/unbescape/html/HtmlEscape

책의 예제대로 따라 했으나 다음 화면과, 다음 로그와 같은 에러가 발생

<브라우저 화면>

Whitelabel Error Page This application has no explicit mapping for /error, so you are seeing this as a fallback. Sat Dec 24 14:08:54 KST 2016 There was an unexpected error (type=Internal Server Error, status=500). org/unbescape/html/HtmlEscape

<서버 에러 로그>

java.lang.NoClassDefFoundError: org/unbescape/html/HtmlEscape at org.thymeleaf.dom.AbstractTextNode.getContent(AbstractTextNode.java:84) at org.thymeleaf.processor.attr.AbstractIterationAttrProcessor.processAttribute(AbstractIterationAttrProcessor.java:84) at org.thymeleaf.processor.attr.AbstractAttrProcessor.doProcess(AbstractAttrProcessor.java:87) at org.thymeleaf.processor.AbstractProcessor.process(AbstractProcessor.java:212)         ...

org/unbescape/htmlHtmlEscape 클래스를 찾을 수 없다고 해서 maven 의존성 추가하니 해결

    org.unbescape
    unbescape
    1.0