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Collections doubt??

Joe Harry
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Joined: Sep 26, 2006
Posts: 9243
    
    1

Guys,

The question below is from Dan Chisholm,



I thought it should have given me a compile time error at Line 3 in the code above, since c1 which is an instance of Map is in a different hierarchy. I'm confused??


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Sanjeev Singh
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Joined: Nov 01, 2006
Posts: 381
System.out.print(c1 instanceof Collection);//Line 3

You are checking the instance (c1 which is of type Object at runtime it is TreeMap)within a same hierarchy..so its OK.
[ December 18, 2006: Message edited by: Sanjeev Kumar Singh ]

~Sanjeev Singh<br />SCJP 1.5
Joe Harry
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Joined: Sep 26, 2006
Posts: 9243
    
    1

Sanjeev, thanks for the help.
Bob CHOI
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Joined: Nov 10, 2006
Posts: 127
You are checking the instance (c1 which is of type Object at runtime it is TreeMap)within a same hierarchy..so its OK.


According JAVA API



Map interface and implementers aren't inherited from Collection, are they?

[ December 18, 2006: Message edited by: Bob CHOI ]
[ December 18, 2006: Message edited by: Bob CHOI ]

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