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Vector.add() compiler warning

 
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I get a compiler warning


What does the second part of the warning mean?
 
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Normally, you don't worry about it. However, for the SCJP, or if your doing any generic programming, you need to worry about it.

If you change the declaration to Vector<Integer> v = new Vector<Integer>() your compiler should shut up. I have not looked, but hopefully there is another thread that talks about generics and there you can study the details of that declaration statement.
 
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As of Java 5, the <E> syntax is the way that you declare a collection's type. Prior to Java 5 there was no way to specify the type of a collection.
In Java 5, if you are sure that your Vector (or in general your Collection) will contain only one type of objects say String, then you decalre it as:

Vector <String> vec = new Vector <String> ();
vec.add("Hello");
[ April 12, 2007: Message edited by: P Lavti ]
 
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Hello Krishna

Vector takes only Objects not primitive types.
 
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Originally posted by chandu:
Hello Krishna

Vector takes only Objects not primitive types.



We are discussing Java 5.0 here where primitive types may be autoboxed into their corresponding wrapper types.
[ April 13, 2007: Message edited by: Barry Gaunt ]
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