Java.io.PushbackReader.ready() Method

Description

The java.io.PushbackReader.ready() method tells whether this stream is ready to be read.

Declaration

Following is the declaration for java.io.PushbackReader.ready() method

public boolean ready()

Parameters

• NA

Return Value

This method returns true if the next read() is guaranteed not to block for input, false otherwise. Note that returning false does not guarantee that the next read will block.

Exception

• IOException -- If an I/O error occurs

Example

The following example shows the usage of java.io.PushbackReader.ready() method.

package com.tutorialspoint;

import java.io.*;

public class PushbackReaderDemo {

   public static void main(String[] args) {

      String s = "Hello World";

      // create a new StringReader
      StringReader sr = new StringReader(s);

      // create a new PushBack reader based on our string reader
      PushbackReader pr = new PushbackReader(sr, 20);
      
      try {
         // check if the reader is ready
         System.out.println("" + pr.ready());


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

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

         // close the stream
         pr.close();

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

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

true
Hello