final ArrayList

[saikrishna cinux]

hi,

I am really confused with this question:

final List ar =new ArrayList();

ar.add("abc");

it will compile and execute with out giving error.

then why we need to put final here?

In case If I want to create readonly arraylist object what can i do ?

so that by using ar.add("abc"); will given an unmodifiable exception

Please help me out


thnaks
Sai

[Thomas Thevis]

In case If I want to create readonly arraylist object what can i do ?
so that by using ar.add("abc"); will given an unmodifiable exception

java.util.Collections has methods for that kind of task. have a look at the API docs.

[Joanne Neal]

It's your object reference ar that is final. You couldn't assign a different ArrayList to it. This would give you an error

final List ar =new ArrayList();
ar = new ArrayList();