String charAt() in java ~ foundjava

Java String charAt()

The java string charAt() method returns a char value at the given index number. The index number starts from 0. It returns StringIndexOutOfBoundsException if given index number is greater than this string or negative index number.

---

Signature

The signature of string charAt() method is given below:

1. public char charAt(int index)  

---

Parameter

index : index number, starts with 0

---

Returns

char value

---

Specified by

CharSequence interface

---

Throws

StringIndexOutOfBoundsException : if index is negative value or greater than this string length.

---

Java String charAt() method example

1. public class CharAtExample{  
2. public static void main(String args[]){  
3. String name="javatpoint";  
4. char ch=name.charAt(4);//returns the char value at the 4th index  
5. System.out.println(ch);  
6. }}  

Output:

t

StringIndexOutOfBoundsException with charAt()

Let's see the example of charAt() method where we are passing greater index value. In such case, it throws StringIndexOutOfBoundsException at run time.

1. public class CharAtExample{  
2. public static void main(String args[]){  
3. String name="javatpoint";  
4. char ch=name.charAt(10);//returns the char value at the 10th index  
5. System.out.println(ch);  
6. }}  

Output:

Exception in thread "main" java.lang.StringIndexOutOfBoundsException: 
String index out of range: 10
at java.lang.String.charAt(String.java:658)
at CharAtExample.main(CharAtExample.java:4)