PrintWriter format(String, Object) method in Java with Examples
Last Updated :
11 Jul, 2025
Improve
The format(String, Object) method of PrintWriter Class in Java is used to print a formatted string in the stream. The string is formatted using specified format and arguments passed as the parameter.
Syntax:
Java
Java
public PrintWriter format(String format, Object...args)Parameters: This method accepts two mandatory parameter:
- format which is the format according to which the String is to be formatted.
- args which is the number of arguments for the formatted string. It can be optional, i.e. no arguments or any number of arguments according to the format.
- NullPointerException This is thrown if the format is null.
- IllegalFormatException This is thrown if the format specified is illegal or there are insufficient arguments.
// Java program to demonstrate
// PrintWriter format(String, Object) method
import java.io.*;
class GFG {
public static void main(String[] args)
{
try {
// Get the parameters
double arg = 47.65734;
String format = "GeeksForGeeks %.8f";
// Create a PrintWriter instance
PrintWriter writer
= new PrintWriter(System.out);
// print the formatted string
// to this writer using format() method
writer.format(format, arg);
writer.flush();
}
catch (Exception e) {
System.out.println(e);
}
}
}
Output:
Program 2:
GeeksForGeeks 47.65734000
// Java program to demonstrate
// PrintWriter format(String, Object) method
import java.io.*;
class GFG {
public static void main(String[] args)
{
try {
// Get the parameters
String arg1 = "GFG";
String arg2 = "GeeksforGeeks";
String format = "A Computer Science "
+ "Portal %1$s, %1$s and %2$s";
// Create a PrintWriter instance
PrintWriter writer
= new PrintWriter(System.out);
// print the formatted string
// to this writer using format() method
writer.format(format, arg1, arg2);
writer.flush();
}
catch (Exception e) {
System.out.println(e);
}
}
}
Output:
A Computer Science Portal GFG, GFG and GeeksforGeeks
