How Can I assert nonprintable control characters format using JMeter? My data which I want to assert is in this small square box, but I am not sure what settings I can do in JMeter to assert it. Please suggest.

<pre><div id="fsWrap"><div id="printReady" class="mainFont"><span vt="I" continuing="YES" vp="0" vr="1" vc="1" vl="1921" vn="V0000000" class="N-U-NORM-E"><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR><BR></span></div><div id="statusbar" class="mainFont"></div></div></pre>

I am trying to use BeanShellPostProcesser but I am not sure how to use it, this is my first time trying to use BeanShellPostProcesser.