The charAt() method of java.nio.CharBuffer Class is used to read the character at the given index relative to the current position.
Syntax:
public final char charAt(int index)
Parameters: This method takes the index of the character to be read, relative to the position; must be non-negative and smaller than remaining().
Return Value: This method returns the character at index position() + index.
Exception: This method throws IndexOutOfBoundsException if the preconditions on index do not hold.
Below are the examples to illustrate the charAt(int index) method:
Example 1:
// Java program to demonstrate// charAt() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Creating the CharBuffer try { // creating object of CharBuffer // and allocating size capacity CharBuffer charbuffer = CharBuffer.allocate(3); // append the value in CharBuffer // using append() method charbuffer.append('a') .append('b') .append('c') .rewind(); // print the CharBuffer System.out.println("Original CharBuffer: " + Arrays.toString( charbuffer.array())); // Read char at particular Index // using charAt() method char value = charbuffer.charAt(2); // Display the value System.out.println("\nvalue at Index 0 is : " + value); } catch (IndexOutOfBoundsException e) { System.out.println("\nindex is greater than" + " the capacity minus 1"); System.out.println("Exception throws : " + e); } }} |
Output:
Original CharBuffer: [a, b, c] value at Index 0 is : c
Example 2: To demonstrate IndexOutOfBoundsException.
// Java program to demonstrate// charAt() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Creating the CharBuffer try { // creating object of CharBuffer // and allocating size capacity CharBuffer charbuffer = CharBuffer.allocate(3); // append the value in CharBuffer // using append() method charbuffer.append('a') .append('b') .append('c') .rewind(); // print the CharBuffer System.out.println("Original CharBuffer: " + Arrays.toString( charbuffer.array())); // Read char at particular Index // using charAt() method char value = charbuffer.charAt(3); // Display the value System.out.println("\nvalue at Index 0 is : " + value); } catch (IndexOutOfBoundsException e) { System.out.println("\nindex is greater than" + " the capacity minus 1"); System.out.println("Exception throws : " + e); } }} |
Output:
Original CharBuffer: [a, b, c] index is greater than the capacity minus 1 Exception throws : java.lang.IndexOutOfBoundsException
Reference: https://docs.oracle.com/javase/9/docs/api/java/nio/CharBuffer.html#charAt-int-
