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How to pass arraylist in methods?

Sandeep Kumar B
Ranch Hand

Joined: Jul 10, 2011
Posts: 45
So, here is my program which is not giving me expected output.
Can someone please explain?

Class file

Test class

Output is

I was expecting to get modified list with ID's as 1,2,3, etc in main method but its not happening
Any idea why?
John Vorwald
Ranch Hand

Joined: Sep 26, 2010
Posts: 139
You only made one object, and then added it 20 times, and kept changing the values in the one object. When you print it, you get the last values set. You need to create new objects in the loop.



For the 2nd option, you could make a copy constructor method.
I agree. Here's the link:
subject: How to pass arraylist in methods?
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