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about the generic method

VuTuan Tran

Joined: Oct 21, 2010
Posts: 14
1.import java.util.*;
2.public class CreateAnArrayList {
3.public <T> void makeArrayList(T t) { // take an object of an unknown type and use a "T" to represent the type
6.List<T> list = new ArrayList<T>(); // now we can create the list using "T";

At line 3. what is the meaning of this public <T> void.I am confusing because unknown type T goes with void in this case.Usually, void is return nothing.
Please help me,thanks
Campbell Ritchie

Joined: Oct 13, 2005
Posts: 46405
I presume you are familiar with this Java™ Tutorials section.

Your method creates a List, adds a T to it, then the List disappears when it goes out of scope, and might be garbage-collected. So it doesn't do anything useful.
I agree. Here's the link:
subject: about the generic method
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