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practice example for young tigers: mixing equailty and autoboxing

 
Greenhorn
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This all started with an innocent question of a mock exam, but when i added some autoboxing features, here's what happend...
So young Tigers, can you spot which line will be printed, and which will (individually) cause a compile-errror or runtime-error?
Enjoy, Renaud

 
Greenhorn
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if (c.equals(d)) System.out.println("c and d are equals");
if (c.equals(e)) System.out.println("c and e are equals");
c is primitive! (compile time error)!

if (a.intValue() == ((Long)b).longValue()) System.out.println("EQ ab");
Invalid cast at compile-time.

I think most others will print, oder?
 
Ranch Hand
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<my-answer excuses-for-being-wrong="tired, beer, it's Sunday">
b == e
a and b are equals
a and c are equals
a and e are equals
b and c are equals
b and e are equals
c and e are equals
java.lang.ClassCastException
</my-answer>

Is your "innocent question" related to the apparant obscure output of the following?

[ February 06, 2005: Message edited by: Tony Morris ]
 
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