Reader markSupported() method in Java with Examples

The markSupported() method of Reader Class in Java is used to check whether this Reader is supports mark() operation or not. It returns a boolean which states if the reader is mark supported.

Syntax:

public boolean markSupported()

Parameters: This method does not accepts any parameters

Return Value: This method returns a boolean value which tells if this Reader supports mark() operation or not. It return true if it is markSupported. Else it returns false.

Below methods illustrates the working of markSupported() method:

Program 1:

// Java program to demonstrate
// Reader markSupported() method

import java.io.*;
import java.util.*;

class GFG {
    public static void main(String[] args)
    {

        try {

            String str = "GeeksForGeeks";

            // Create a Reader instance
            Reader reader
                = new StringReader(str);

            // Check if the Reader is
            // markSupported using markSupported()
            System.out.println("Is Reader markSupported: "
                               + reader.markSupported());

            reader.close();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

Output:

Is Reader markSupported: true

Program 2:

// Java program to demonstrate
// Reader markSupported() method

import java.io.*;
import java.util.*;

class GFG {
    public static void main(String[] args)
    {

        try {
            char[] str = { 'G', 'E', 'E', 'K', 'S' };

            // Create a Reader instance
            Reader reader
                = new CharArrayReader(str);

            // Check if the Reader is
            // markSupported using markSupported()
            System.out.println("Is Reader markSupported: "
                               + reader.markSupported());

            reader.close();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

Output:

Is Reader markSupported: true

Reference: https://docs.oracle.com/javase/9/docs/api/java/io/Reader.html#markSupported–