Java StringBuffer charAt() Method

// Java program to demonstrate charAt() method
public class CharAt {
  
    public static void main(String[] args) {
      
        StringBuffer b = new StringBuffer("Java Programming");

        // Using charAt() to get the 
        // character at index 5
        char ch = b.charAt(5);  
        System.out.println("" + ch);
    }
}

// Java program to demonstrate 
// invalid negative index in charAt()
public class CharAt {
  
    public static void main(String[] args) {
      
        StringBuffer b = new StringBuffer("Java Programming");

        try {
            // Using a negative index
            System.out.println("Character at index -1: " 
                               + b.charAt(-1));  
        } catch (StringIndexOutOfBoundsException e) {
            System.out.println("Exception: " + e);
        }
    }
}

// Java program to demonstrate invalid index 
// greater than length in charAt()
public class CharAt {
  
    public static void main(String[] args) {
      
        StringBuffer b = new StringBuffer("Java Programming");

        try {
            // Using an index greater than the length of the buffer
            System.out.println("Character at index 20: " 
                               + b.charAt(20));  
        } catch (StringIndexOutOfBoundsException e) {
            System.out.println("Exception: " + e);
        }
    }
}