Let me start by saying that I can't put any code here because Internet on my laptop is not working so I am posting this through my phone. Okay the problem is that say I have two classes: class one and two. Class one has an ArrayList as one of its attributes and it calls a void method from class two and passes that ArrayList as a parameter. Now that method initializes another ArrayList and makes it equal to the parameter passed by me and makes changes to that new ArrayList. Funny thing is that even my original ArrayList which was passed as parameter is also changing. What could be the possible reason?

java arrays arraylist
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