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Passing null

 
Greenhorn
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I suppose at 2 also, System.out.print() uses toString(). How come only at
1 there is exception while at 2 it is not ?
 
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The printf() method does not directly call toString() on the object; instead, it uses String.valueOf(x).

String.valueOf(...) first checks if the object is null, and if so, it returns the string "null", otherwise it returns x.toString(). See the API documentation of String.valueOf(...).
 
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Thats Correct. It first checks the object for null and if not, then only it invokes toString() method on the object.

Thanks Jesper Young.
 
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Is there a rule why actually m(String x) got executed instead of m(Object x) ?

thanks
 
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Originally posted by Martin Jedrzejewski:
Is there a rule why actually m(String x) got executed instead of m(Object x)?

Have a look at What is a most-specific method?
 
Sweta Pillai
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Thanks guys !
 
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