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type casting

 
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can an Arraylist be typecast to a vector?
 
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No. But they both extend AbstractList, so you can typecast to that.
 
Renu Radhika
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Thanks a lot
 
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Originally posted by Ulf Dittmer:
No. But they both extend AbstractList, so you can typecast to that.


True, but note that AbstractList's public methods are precisely
the same as List's, so I would more likely write:

On the other hand, I think the OP wanted to *cast* ("convert*) an existing ArrayList
to a Vector: you can't do that, but you can create a new Vector that
holds copies of the references found in the ArrayList:

Note that v != arrayList, although v.equals(arrayList).

Of course, in the best of all possible worlds, just being of type List should suffice!
 
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I would mention two principles here that are useful:

1. Vector is old and kind of discouraged. Avoid its use unless there is legacy code which you must add your code to.

2. Use Collections 2 and always strive to use references of the base-interface type. E.g.,

List list = // new ArrayList();
public List getItems(){...}

This way, the implementation can be changed when needed.
 
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A lot of classes in javax.swing expect a Vector in the constructor (or an array) but not an arraylist.
That's often a reason for using Vector.
 
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