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APIs for std classes??

 
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Hi all,
I need some advice. I saw couple of mock exams and read some of the messages in this forum. I was wondering how good one should be in the APIs for classes like Integer, Float, Double etc i.e. basic numeric types. I also saw couple of questions that tests your knowledge on NaN, +ve/-ve infinity etc. In that case I think one should really know the std api really well. Any help would be appreciated.
truly,
Deep
 
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Deep -
First off the 'Wrapper' classes: (Integer, Float, Double, etc),
If you only know a little about the wrapper classes, understand these THREE sets of methods (they are the MOST important),
xxxValue( ), parseXxx( ), valueOf( )
Next thing, know their constructors. In spite of what the Sun objectives say, you DON'T have to know about getXxx( ) - that's a mistake on the Sun objectives, it's NOT on the test (One less thing to worry about!)
Here's what you have to know about class Object:
equals( ) and hashCode( ) and equals( ) vs == VERY IMPORTANT
finalize( ) (garbage collector stuff)
toString( )
notify( ), notifyAll( ), wait( ), (threads struff)
For Collections:
Interfaces: Collection, Set, Map, List, SortedSet, SortedMap
Understand when to use the following:
HashMap, Hashtable, TreeMap, LinkedHashMap
HashSet, LinkedHashSet, TreeSet
ArrayList, Vector, LinkedList
The key to these is what they're good for! What special thing they can do - you don't need to know their methods.
You need to know about iterators!
In terms of NaN and 'the infinities'.... hmmm...
You 'might' get a question on these... There are lots of little details and IMHO I would make sure I have EVERY OTHER topic totally under control before I'd put much effort into these. Another way of saying this is that with NaN and 'the infinities', there's not a lot of bang for the buck.
Hope that helps, was there another topic you were interested in?
-Bert
 
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime.
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