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format() question

Tamara Lopez
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Joined: Feb 21, 2006
Posts: 63
As part of Q9 Chapter 6(p503) in K&B:
Will this compile:
System.out.format("%s",new Long("123"));

The answer is yes.

But new Long would return a Long - which is not a String. But it does work. Why??
Oscar Gonzalez
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Joined: Mar 28, 2006
Posts: 63
The Long.toString() method is called to make the cast. The compiler says: "I know you want to convert the Long to a String and do it automaticaly"

Changchun Wang
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Joined: Feb 15, 2006
Posts: 83
because it implicitly invoke the new object`s toString{}
I agree. Here's the link:
subject: format() question
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