StringBuffer codePointAt() method in Java with Examples

The codePointAt() method of StringBuffer class returns a character Unicode point at that index in sequence contained by StringBuffer. This method returns the “Unicodenumber” of the character at that index. Value of index must be lie between 0 to length-1.
If the char value present at the given index lies in the high-surrogate range, the following index is less than the length of this sequence, and the char value at the following index is in the low-surrogate range, then the supplementary code point corresponding to this surrogate pair is returned. Otherwise, the char value at the given index is returned.

Syntax:

public int codePointAt(int index)

Parameters: This method takes one parameter index which is int value representing index of the character whose unicode value to be returned.

Return Value: This method returns unicode number of the character at the specified index.

Exception: This method throws IndexOutOfBoundsException when index is negative or greater than or equal to length().

Below programs demonstrate the codePointAt() method of StringBuffer Class:

Example 1:

// Java program to demonstrate
// the codePointAt() method

class GFG {
    public static void main(String[] args)
    {

        // create a StringBuffer object
        StringBuffer str = new StringBuffer();

        // add the String to StringBuffer Object
        str.append("Geeksforgeeks");

        // get unicode of char at position 10
        int unicode = str.codePointAt(10);

        // print the result
        System.out.println("Unicode of Character "
                           + "at Position 10 "
                           + "in StringBuffer = "
                           + unicode);
    }
}

Output:

Unicode of Character at Position 10 in StringBuffer = 101

Example 2: To demonstrate IndexOutOfBoundsException

// Java program demonstrate
// IndexOutOfBoundsException thrown by
// the codePointAt() Method.

class GFG {
    public static void main(String[] args)
    {
        // create a StringBuffer object
        // with a String pass as parameter
        StringBuffer
            str
            = new StringBuffer("GeeksForGeeks Contribute");

        try {

            // get char at position 25 which is
            // greater then length
            int i = str.codePointAt(25);
        }

        catch (IndexOutOfBoundsException e) {
            System.out.println("Exception: " + e);
        }
    }
}

Output:

Exception: java.lang.StringIndexOutOfBoundsException: String index out of range: 25

References:
https://docs.oracle.com/javase/10/docs/api/java/lang/StringBuffer.html#codePointAt(int)