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Java Java Data Structures - Retired Exploring the Java Collection Framework Lists

Kevin Frostad
Kevin Frostad
3,483 Points
Posted by Kevin Frostad
Kevin Frostad
3,483 Points

Why do we need to specify the type of the class when making an object of ArrayList?

Wouldn't it be enough to only specify which type the object can hold, like:

ArrayList<String> list = new ArrayList<>()

Instead of:

ArrayList<String> list = new ArrayList<String>()
Kevin Faust
Kevin Faust
15,353 Points
Kevin Faust
Kevin Faust
15,353 Points

//editted for readability

1 Answer

Kevin Faust
Kevin Faust
15,353 Points
Kevin Faust
Kevin Faust
15,353 Points

Yes your completely right. The first option you have presented is a common way of handling generics. I believe later on in the videos, you will learn that either or is acceptable. Personal preference really

Brendon Butler
Brendon Butler
4,254 Points
Brendon Butler
Brendon Butler
4,254 Points

Yeah, it's weird. I was always taught to type it out in its entirety, and my IDEs even stopped the code from compiling because of these issues. Things seem to have changed now and my IDEs tell me not to put them in because it's redundant.