what is meant by UP& DOWN casting in java?
Answers were Sorted based on User's Feedback
Answer / sabeetha
Down Casting is nothing but casting down the inheritance
tree to a more specific class i.e casting a superclass to
subclass.
Upcasting- casting up the inheritance tree to a more general
type. It is done implicitly (i.e typing in the cast is not
required). Its because the classes at lower level of
hierarchy have all those features that are present in the
classes above them in the inheritance hierarchy. So they can
be upcasted implicitly ( like Dog IS-A Animal).
I got this answer
from(http://javaforyou.wordpress.com/2008/06/22/casting-reference-variables-downcasting-upcasting/)
with example.
Is This Answer Correct ? | 19 Yes | 2 No |
Answer / paritala.veeraiah chowdary
Casting is the process of converting one data type in to
another.Converting smaller data type into higher data type
is known as up casting.Where as the process of converting
higher data type to lower is known as down casting.
Is This Answer Correct ? | 24 Yes | 9 No |
Answer / regalla soujanya naresh reddy
A super class reference can be converted into a subclass
reference but this
subclass reference is not useful to call the methods of any
of the classes. This convention is known as Downcasting.
We can convert the subclass reference to a superclass
reference without using the cast operation compiler because
it will internally take care of the casting. This is known
as Upcasting.
Is This Answer Correct ? | 9 Yes | 0 No |
Answer / keli
UP CASTING: it is the process of assigning subclass reference to the super class.
DOWN CASTING:the process of assigning superclass reference to subclass
Is This Answer Correct ? | 6 Yes | 4 No |
Answer / javachi
Casting is nothing but data type conversion.
Up casting is the conversion of data type from lower range data type to higher data type eg: int to long, byte to long, int to double etc...
Down casting is vice versa of up casting, here we do type casting from larger value to lower value,
eg: double to byte, long to int etc
Is This Answer Correct ? | 2 Yes | 4 No |
Answer / jack
i think.. UPcasting is converting one type to another
without any loss of data... and DOWNcasting is converting
one type to another with loss of data
Is This Answer Correct ? | 7 Yes | 20 No |
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