-The core group of tags are the most frequently used JSTL tags.
-the JSTL core tag provides variable support, URL management , flow control etc.
Syntax to include JSTL core library in your JSP:
1. | c:out | It display the result of an expression, similar to the way <%=..%> tag work. E.g<c:out value="${'Welcome to JSTL'}" /> |
2. | c:import | It is similar to jsp 'include', with an additional feature of including the content of any resource either within server or outside the server. E.g<c:import var="data" url="http://www.xyz.com"/> |
3. | c:set | It is used to set the result of an expression evaluated in a 'scope'. This tag is similar to jsp:setProperty action tag. E.g<c:set var="Income" scope="session" value="${4000*4}" /> |
4. | c:remove | It is used for removing the specified scoped variable from a particular scope. E.g<c:set var="income" scope="session" value="${4000*4}" /> <c:remove var="income" /> |
5. | c:if | It is conditional tag used for testing the condition and display the body content only if the expression evaluates is true. E.g<c:if test="${income > 8000}"> <p>My income is:<c:out value="${income}" /></p> </c:if> |
6. | c:catch | It is used for catching any Throwable exceptions that occurs in the body and optionally exposes it. E.g<c:catch var="MyException"> <% int x=2/0; %> </c:catch> |
7. | c:choose | It is a conditional tag that establish a context for mutually exclusive conditional operations. It works like a Java switch statement in which we choose between a numbers of alternatives. |
| c:when | It is subtab of <choose> that will include its body if the condition evaluated be 'true'. |
| c:otherwise | It is also subtab of <choose> it follows <when> tags and runs only if all the prior condition evaluated is 'false'. |
| | The <c:when> and <c:otherwise> works like if-else statement. But it must be placed inside <c:choose tag>. E.g<c:choose> <c:when test="${marks > 75}"> Congratulations ! You hold Distinction </c:when> <c:otherwise> Sorry! Result is unavailable. </c:otherwise> </c:choose> |
8. | c:forEach | It is an iteration tag used for repeating the nested body content for fixed number of times. The <c:forEach> tag is most commonly used tag because it iterates over a collection of object. E.g<c:forEach var="i" begin="0" end="5"> count <c:out value="${i}" /> </c:forEach> |
9. | c:forTokens | It iterates over tokens which is separated by the supplied delimiters. E.g<c:forTokens items="DIET-Department" delims="-" var="name"> |
10. | c:url | This tag creates a URL with optional query parameters. It is used for url encoding or url formatting. This tag automatically performs the URL rewriting operation. E.g<c:url value="/MyJspFile.jsp" /> |
11. | c:param | It allow the proper URL request parameter to be specified within URL and it automatically perform any necessary URL encoding. E.g<c:param name="CollegeCode" value="054"> </c:param> |
12. | c:redirect | This tag redirects the browser to a new URL. It is used for redirecting the browser to automatically perform any necessary URL encoding. E.g<c:redirect url="http://xyz.com" /> |
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