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generic collections

 
Paula Murphy
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I am unsure about generics and i have a few questions:

What are the rules regarding passing a generic collection as an argument to a method where the method parameter is
1. a non generic collection?
2. a generic collection?

What are the rules for passing a non generic collection as an argument to a method where the method parameter is a generic collection?

If you override a method, with a generic parameter, does the overriding method have to have a parameter with the same generic?
 
Seetharaman Venkatasamy
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Posts: 5575
Eclipse IDE Java Windows XP
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Welcome to JavaRanch


Paula Murphy wrote:
What are the rules regarding passing a generic collection as an argument to a method where the method parameter is
1. a non generic collection?
2. a generic collection?


you can pass. you will get *warning* if the parameter or argument is not a generic

Paula Murphy wrote:What are the rules for passing a non generic collection as an argument to a method where the method parameter is a generic collection?

you can pass[vice-versa is true also] . there is an only one rule is that *always use generic*

Paula Murphy wrote:If you override a method, with a generic parameter, does the overriding method have to have a parameter with the same generic?


say super class has a method which has generic parameter , but overriding method in subclass can have non-generic parameter[but it cant have different generic type] . but vice-versa is not true.

the thumb rule is that dont mix non-generic collection into generic collection

hth
 
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