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Java PushbackInputStream markSupported() Method with Example

PushbackInputStream Class markSupported() method: Here, we are going to learn about the markSupported() method of PushbackInputStream Class with its syntax and example.
Submitted by Preeti Jain, on April 20, 2020

PushbackInputStream Class markSupported() method

• markSupported() method is available in java.io package.
• markSupported() method is used to check whether this stream supports mark(), reset() or not.
• markSupported() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• markSupported() method does not throw an exception at the time of checking supporting methods.

Syntax:

    public boolean markSupported();

Parameter(s):

• It does not accept any parameter.

Return value:

The return type of the method is boolean, it returns true when this stream support mark() method otherwise it returns false.

Example:

// Java program to demonstrate the example 
// of boolean markSupported() method of
// PushbackInputStream

import java.io.*;

public class MarkSupportedOfPBIS {
    public static void main(String[] args) throws Exception {
        byte[] b_arr = {
            97,
            98,
            99,
            100
        };
        InputStream is_stm = null;
        PushbackInputStream pb_stm = null;

        try {
            // Instantiates ByteArrayOutputStream and PushbackInputStream
            is_stm = new ByteArrayInputStream(b_arr);
            pb_stm = new PushbackInputStream(is_stm);

            // By using markSupported() method is to
            // check whether this stream supports
            // mark() method or not
            boolean status = pb_stm.markSupported();
            System.out.println("pb_stm.markSupported(): " + status);
        } catch (Exception ex) {
            System.out.println(ex.toString());
        } finally {
            if (is_stm != null)
                is_stm.close();
            if (pb_stm != null)
                pb_stm.close();
        }
    }
}

Output

pb_stm.markSupported(): false