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Java Java Basics Getting Started with Java Strings and Variables

Brady Cramer
Brady Cramer
659 Points
Posted by Brady Cramer
Brady Cramer
659 Points

%s how does it know that firstName should replace it? is it because the printf hidden fuctions have %s inside the code?

I am confused on how it new for %s to be replaced by firstName. Is it because in the program we are using or language (still new), it is already a command inside of printf that when %s is used it will appear as what you put after a comma?

sorry if that is not clear. I am just confused on how it was able to do that without us telling it to replace %s with firstName.

1 Answer

Monde Ngalonkulu
Monde Ngalonkulu
12,051 Points
Monde Ngalonkulu
Monde Ngalonkulu
12,051 Points

Well, the printf method takes a format string and some values. A formatted string is one that has formatting in it (instead of the normal strings). And the %s is a tells printf to insert a string there. And since firstName is a string, it works.

See printf docs here: https://docs.oracle.com/javase/8/docs/api/java/io/PrintWriter.html