• Open a JSP file
• Add an EL reference to an undefined EL variable, like

${foo}

- See the variable being highlighted in yellow
- Before this reference line, add a useBean declaration

<jsp:useBean id="foo" class="String" scope="request"/>

- The ${foo} is still hilighted in yellow.

• Close the file and wait for awhile and open it again, the unresolved variable warning is resolved.

Comparing to Java file, this takes long time.