ArrayList - How to modify a member of an object?

java collections pojo
user1318796 picture user1318796 · Apr 7, 2012 · Viewed 123.2k times · Source

I have a number of Customer objects stored in an ArrayList. My Customer class has 2 data members: Name and Email. Now I want to modify just the Email for Customer "Doe".

Now if "Doe" is located at index 3 in the list, I know I can write this line:

myList.set( 3, new Customer( "Doe", "[email protected]" ) );

But that means creating a new object. If I have a very big list, I suppose the process would be very slow. Is there any other way to directly access the data member of an Object stored in an ArrayList, maybe by using another kind of Collection than ArrayList?

Answer

Random42 picture Random42 · Apr 7, 2012

You can do this:

myList.get(3).setEmail("new email");

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