Run java class from inside matlab (previous question reference)

I stumbled upon the same issue as the one discussed here https://ch.mathworks.com/matlabcentral/answers/30377-is-there-an-implementation-of-tarjan-s-algorithm-for-triconnected-components-of-a-graph-in-matlab .

However, I was not able to reproduce the answer, I think I am missing something.

Step 1: The link is out of date, so I created the jar by myself. Then I used javaaddpath as shown.

Step2: I have the TriComps java class in a separate .cpp file when I run the triconnected_components function I get an error at line 30 : trc = TriComps; undefined function or variable.

Who can I actually declare that this is a java class?

[Guillaume]

"I have the TriComps java class in a separate .cpp file

.cpp files are typically C++ source files, not compiled java files (typically .jar files). They're two completely different beasts.