assert JavaServer Page tag
Use the assert
JavaServer Page tag to improve processing efficiency
when displaying the results of the Obj-List method.
Summary
In an activity that uses the Obj-List method, you identify the concrete classes for the
Page List
property that holds the results from the method. However, when
you display the Page List
in an HTML display, the system has no way — other
than the Assert tag — to indicate in the HTML which classes are involved.
Accordingly, at runtime the system rechecks the class of each page in the list. The
pega:assert
tag provides a way to indicate in the HTML which classes to
use for each page.
If you're working with a class group, use the elseassert
option for each
class in the class group. In addition, use a final elseassert
option to
display something when the system doesn't find anything in any of the classes listed.
Someone later might add a class to a class group and neglect to update the Assert tag in
HTML forms. In such cases, the elseassert
option can be important for
debugging.
Complete syntax
In the syntax presentations below:
- Square bracket characters
[
and]
define optional parts of the tag. Do not type the brackets. - JSP delimiters <pega: and /> mark the start and end of the tag.
- Replace any text in italics with your choice of value of that type.
<pega:assert name="class-name1" >
insert content
<pega:elseassert name="class-name2" />
insert content
<pega:elseassert />
insert default content
</pega:assert>
Example
For example, in a worklist, the data belongs to a page of class
Code-Pega-List. Each pxResults
page is limited to one
or a few classes. The assert tag reduces the number of rules the system reads to generate
the display.
<pega:forEach name=".pxResults" >
<pega:withEmbedded name="$this" >
<pega:assert name="Assign-Worklist" >
insert row definition
</pega:assert>
</pega:withEmbedded >
</pega:forEach>
You can assess the benefits of the assert tag by using the Performance tool to compare the Rule Count number when the assert tag is used with the number when it is not used.