Java.io.Reader.markSupported() Method

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