Load .vsd file having a block diagram and edit some text blocks from the diagram

I have a full diagram created in MS Visio file and some texts in the diagrams should be edited.
for proof of concept I should be able to atleast detect one text box and edit it.
I am not able to load .vsd file and detect text box.
Can you please help me with the sample code? Do we need to load master stencils for this code?
I am writing sample code in Java language using Eclipse IDE.

It will be great if you can tell me the sequence of APIs to be used. I already have a java code from github but I am not sure how to use it in my problem statement.

@sayli

In order to add/update the shape text in a diagram, please check below article(s) in the API documentation:

In case you face any issue, please share your sample source Visio file along with expected output. We will test the scenario in our environment and address it accordingly.