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12.6. Evaluating Items Conditionally

JSTL provides two main tags for performing conditional evaluation: if and choose. The if tag evaluates its body only when a specified test condition is true. There is no “else” condition—the content is either included or omitted with no alternative content. The following list summarizes the use of if; the following subsections give details and examples.

• The if tag in the jr library. Use a JSP expression for the test attribute; if the result is true or Boolean.TRUE, the contents of the tag are evaluated. For example:

  <jr:if test="<% expression %>"> 
    HTML or JSP content. 
  </jr:if> 

• The if tag in the jx library. Use the same basic syntax as with the jr library, but specify the test by accessing an existing attribute ...