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Java Java Basics Getting Started with Java IO

Posted by Arjun Verma
Arjun Verma
174 Points

How exactly does the String formatter work and why must it be used? I'm used to java and haven't really ever used it?

Please help

IO.java 
// I have imported java.io.Console for you.  It is a variable called console.
String firstName;
firstName = console.readLine();
String lastName = console.readLine();
console.printf("First name: " + firstName);

1 Answer

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Arjun, printf() takes a String that contains format specifiers as its first parameter and a variable for each format specifier as its additional parameters. There's lots of documentation for it, and examples, on the web.

// I have imported java.io.Console for you.  It is a variable called console.
String firstName = console.readLine();
String lastName = console.readLine();
console.printf("First name: %s", firstName);

Here the format specifier is %s (which means it is a placeholder for a String variable), and the variable whose value will replace the specifier is firstName. The format specifier for ints is %d, and there are a few more.

Arjun Verma
Arjun Verma
174 Points

Thank you jcorum!