To use the Logic Tag Library in a Struts application, your application's JSPs must declare their use of the library with a JSP taglib directive:
<%@ taglib uri="http://struts.apache.org/tags-logic" prefix="logic" %>
Notice that the prefix attribute is set to "logic." This attribute can be set to whatever you want; however, "logic" is the accepted default for the Logic Library. The prefix attribute declares the prefix that each tag must have when it is used in the JSP, as shown here:
<logic:present name="searchForm" property="results">
Because "logic" was defined as the prefix, the present tag was used as shown. However, if you chose to use a prefix of "strutslgc", the tag would be used the following way:
<strutslgc:present name="searchForm" property="results">
Note | Modern application servers use the uri attribute of the taglib directive to automatically resolve the location of the tag library descriptor file. Older application servers that support only JSP version 1.1 and/or version 1.0 require that tag libraries be registered in the web.xml file so that they can be resolved, as shown here:
<taglib> <taglib-uri>http://struts.apache.org/tags-logic</taglib-uri> <taglib-location>/WEB-INF/tlds/struts-logic.tld</taglib-location> </taglib> |