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e1068. Saving and Emitting HTML Fragments Using JSTL in a JSP Page

When saving text with the special characters <>'"&, the special characters are save as is; there is no translation that takes place. However, when emitting text with <c:out>, these special characters are translated to the equivalent XML entities. In particular, < becomes <, > becomes >, ' becomes ', " becomes ", and & becomes &. This means that a value such as <b> will be emitted as <b> and therefore not be interpreted as the HTML b tag.

To prevent this translation, the escapeXml attribute must be specified and set to false:

    <%-- Declare the core library --%>
    <%@ taglib uri="/WEB-INF/tld/c.tld" prefix="c" %>
    
    <%-- Save data with html tags --%>
    <c:set var="msg" value="hi <b>John</b>!" scope="page" />
    
    <%-- Show the value after translating special characters --%>
    <c:out value='${msg}' />
    
    <%-- Show the value without translating special characters --%>
    <c:out value='${msg}' escapeXml="false" />