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:
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.
Return Value: This method returns this PrintWriter instance.
Exception: This method throws following exceptions:
- NullPointerException This is thrown if the format is null.
- IllegalFormatException This is thrown if the format specified is illegal or there are insufficient arguments.
Below methods illustrates the working of format(String, Object) method:
Program 1:
// 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:
GeeksForGeeks 47.65734000
Program 2:
// 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 = "Lazyroar"; 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 Lazyroar
