printf of a boolean

[Leonard Fischer]

When I run the following, it prints true.

System.out.printf("%b", new Object());

seems like any second arg will print true, except a boolean false.

Just curious about this...

[Ireneusz Kordal]

Hi,

look at spec (section: Conversion): http://www2.selu.edu/Academics/Faculty/kyang/docs/api/java/util/Formatter.html#syntax

'b', 'B' ................ If the argument arg is null, then the result is "false". If arg is a boolean or Boolean, then the result is string returned by String.valueOf(). Otherwise, the result is "true".

Argument isn't null nor Boolean, so print("%b", new Object()) prints 'true'

[Leonard Fischer]

Thanks!

[sweety sinha]

class checkdate 
{
	boolean b;
	checkdate(boolean a){
		b = a;
	}
	public static void main(String[] args) 
	{
		System.out.printf("%b",new checkdate(false));
	}
}

why this is giving true when it should give false as answer.

[Vijitha Kumara]

sweety sinha wrote:why this is giving true when it should give false as answer.

How?

Well, It has no difference from using "new Object()" in this conext. Check PrintStream for more details.