JSTL Functions

Following are the tutorial links for useful JSTL functions with examples. Following Taglib directive should be included in the JSP page in order to use the JSTL functions.

<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>

1. fn:contains function: This function checks whether the given string is present in the input as sub-string. It does a case sensitive check.
2. fn:containsIgnoreCase(): It does a case insensitive check to see whether the provided string is a sub-string of input.
3. fn:indexOf(): It is used for finding out the start position of a string in the provided string. Function returns -1 when string is not found in the input.
4. fn:escapeXML(): It is used for HTML/XML character escaping which means it treats html/xml tags as a string. Similar to the escapeXml attribute of <c:out> tag.
5. fn:join() and fn:split() functions: JSTL functions: fn:join() concatenates the strings with a given separator and returns the output string. fn:split() splits a given string into an array of substrings.
6. fn:length(): The JSTL function fn:length() is used for computing the length of a string or to find out the number of elements in a collection. It returns the length of the object.
7. fn:startsWith(): It checks the specified string is a prefix of given string.
8. fn:endsWith(): fn:endsWith() JSTL function is used for checking the suffix of a string. It checks whether the given string ends with a particular string.
9. fn:substring(): This JSTL function is used for getting a substring from the provided string.
10. fn:substringAfter(): It is used for getting a substring which is present in the input string before a specified string.
11. fn:substringBefore(): It gets a substring from input which comes after a specified string.
12. fn:trim(): JSTL Function fn:trim() removes spaces from beginning and end of a string and function.
13. fn:toUpperCase(): It is just opposite of fn:toLowerCase() function. It converts input string to a uppercase string.
14. fn:toLowerCase(): This function is used for converting an input string to a lower case string.
15. fn:replace(): fn:replace() function search for a string in the input and replace it with the provided string. It does case sensitive processing.