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Generics -really very hard question

sree visu
Ranch Hand

Joined: Jul 05, 2007
Posts: 133
for the following line what are legal

Map<Integer,String> map=new HashMap<Integer,String>

what are legal

1. for(Map.Entry pairs :map.entrySet()){}
2. Iterator i=map.entrySet().iterator();
3. Iterator i=map.iterator();
4. Iterator<Map.Entry<Integer,String>> i=map.entrySet().iterator();
5. Iterator<Map.Entry> i=map.entrySet().iterator


in the question i couldn't understand anything and i am totally blank
can any one please guide me regarding the each answer and state
why it is legal or illegal

Please do help me in this regard and thanks in advance


Regards<br />Sree Visu<br />SCJP 5.0, SCWCD 5.0, SCJD(Preparing B&S 2.2.2)
Alex Belisle Turcot
Ranch Hand

Joined: Apr 26, 2005
Posts: 516
Hi,

I would strongly suggest you paste all this into a java editor:



You'll see some errors. I fix some lines in your code which I thought were typo, but you know better, make sure you have the correct text.

Lines 3 and 5 give me errors:
3: Map doesn't have the iterator method, would need to be casted.
5: <Map.Entry> does not match the declared <Integer,String>

Alex
Dean Jones
Ranch Hand

Joined: Dec 29, 2007
Posts: 129
I am getting compilation errors for lines 2,3,4 and 5. Can someone please explain in details.
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: Generics -really very hard question
 
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