The ready() method of Reader Class in Java is used to check whether this Reader is ready to be read or not. It returns a boolean which states if the reader is ready.
Syntax:
public void ready()
Parameters: This method does not accepts any parameters
Return Value: This method returns a boolean value which tells if this Reader is ready to be read or not. It return true if it is ready. Else it returns false.
Exception: This method throws IOException if some error occurs while input-output.
Below methods illustrates the working of ready() method:
Program 1:
// Java program to demonstrate// Reader ready() 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 // ready to be read using ready() System.out.println("Is Reader ready " + "to be read: " + reader.ready()); // Get the character // to be read from the stream int ch; // Read the first 5 characters // to this reader using read() method // This will put the str in the stream // till it is read by the reader for (int i = 0; i < 5; i++) { ch = reader.read(); System.out.println("\nInteger value " + "of character read: " + ch); System.out.println("Actual " + "character read: " + (char)ch); } reader.close(); } catch (Exception e) { System.out.println(e); } }} |
Output:
Is Reader ready to be read: true Integer value of character read: 71 Actual character read: G Integer value of character read: 101 Actual character read: e Integer value of character read: 101 Actual character read: e Integer value of character read: 107 Actual character read: k Integer value of character read: 115 Actual character read: s
Program 2:
// Java program to demonstrate// Reader ready() 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); reader.close(); // Check if the Reader is // ready to be read using ready() System.out.println("Is Reader ready " + "to be read: " + reader.ready()); // Get the character // to be read from the stream int ch; // Read the first character // to this reader using read() method // This will put the str in the stream // till it is read by the reader ch = reader.read(); System.out.println("\nInteger value " + "of character read: " + ch); System.out.println("Actual " + "character read: " + (char)ch); reader.close(); } catch (Exception e) { System.out.println(e); } }} |
Output:
java.io.IOException: Stream closed
Reference: https://docs.oracle.com/javase/9/docs/api/java/io/Reader.html#ready–
