Java.io.Reader.markSupported() Method

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Description

The java.io.Reader.markSupported() method tells whether this stream supports the mark() operation.

Declaration

Following is the declaration for java.io.Reader.markSupported() method.

public boolean markSupported()

Parameters

NA

Return Value

This method returns true if and only if this stream supports the mark operation.

Exception

IOException − If the stream does not support mark(), or if some other I/O error occurs.

Example

The following example shows the usage of java.io.Reader.markSupported() method.

package com.tutorialspoint;

import java.io.*;

public class ReaderDemo {
   public static void main(String[] args) {
      String s = "Hello World";

      // create a new StringReader
      Reader reader = new StringReader(s);

      try {
         // read the first five chars
         for (int i = 0; i < 5; i++) {
            char c = (char) reader.read();
            System.out.print("" + c);
         }

         // change line
         System.out.println();

         // check if mark is supported
         System.out.println("" + reader.markSupported());

         // close the stream
         reader.close();

      } catch (IOException ex) {
         ex.printStackTrace();
      }
   }
}

Let us compile and run the above program, this will produce the following result −

Hello
true