When logic for exception handling is defined in struts-config.xml or within the action tag, it’s known as declarative exception handling in Struts.
In the following example, we have defined exception in struts-config.xml file for NullPointerException:
[xml]
<global-exceptions>
<exception key=”test.key”
Type=”java.lang.NullPointerException”
Path=”/WEB-INF/errors/error_page.jsp”
</global-exceptions>
[/xml]