Do we have to approve every object creation in java?

Question

Sounds a dumb question with an obvious answer :)

Nevertheless, I ventured to ask you to be doubly sure.

We really use the statements below.

ArrayList alProperties = new ArrayList();

assert alProperties != null : "alProperties is null";

The problem is that creating a small and simple document to follow is difficult. There are many books on statements, but ideally I would like to give the new programmer very simple recommendations on using something like statements. Btw, is there any tool like pmd for using assertions correctly?

Thanks in advance.

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