Alireza

In other words, when you convert hashMap elements to array you will get new objects. Right? So the hashCode of these new objects are different. So when you use these objects i...

Is Notepad an IDE?!! Are you sure that you know what is an IDE exactly? 😂😂

Have you any cors error in your log in the cosole of browser?

Not sdk dude, do you use maven or some other package managers?

Ok, do you sure you built the jar file in correct way?

Are your other dependencies in your classpath?

What was the exception?

You can use jar file as library in servlet. Can you?

a jar file or war??!