Grails ?????????????? The Grails Custom Tag Library

Grails???????GSP?JSP??????????????????????????????????????

• JSP?Java???????????GSP??????????groovy???
• GSP??????${..} ???Groovy???(eg. test="${it=='true'}")?JSP??JSTL???????????????????????
• JSP? TLD????????????????????????GSP??Grails ?????? ?? ????????????????????????JSTL??????????
• GSP????????GString????????JSP?? <c:out value="${it}" /> ???????????????????

??????????????????GSP?JSP??????????????????????????????

1. GSP????????
2. JSP????????

{excerpt:hidden=true} Grails supports both GSP and JSP as view technologies. There are however some key differences between the 2 view technologies which are listed below:

• GSP uses groovy inside scriptlets while JSP is Java
• GSP attribute values when surrounded with the ${..} (eg. test="${it=='true'}") syntax are Groovy expressions, while in JSP these are JSTL expressions (and hence more limited)
• JSP supports custom tag libraries through the TLD while GSP supports custom tag libraries with Grails Dynamic Tag Libraries and does not support JSTL
• GSP supports GString expressions inside the content whilst JSP requires you to use <c:out value="${it}" />

There are many shared tags but some additional ones for both GSP (mainly groovy syntax tags) and JSP hence we have 2 reference sections:

1. GSP Tag Reference
2. JSP Tag Reference {excerpt}