IndexOutOfBoundsException in Java

IndexOutOfBoundsException is a runtime exception which occurs when we try to access an index that is out of range of a certain array, List or String in Java. This exception is thrown by the JVM when the index being accessed is either negative or greater than the size of the array or List.

Causes of IndexOutOfBoundsException

There are several ways in which we can cause an IndexOutOfBoundsException in Java:

• If we try to access an element using an index greater than or equal to the size of an array, List or String, this exception is thrown.
• If we try to access an element using an index less than zero, an IndexOutOfBoundsException is thrown.
• If we try to remove an element from an empty List or String, an IndexOutOfBoundsException is thrown.

Example Code

Here is an example code which will show you how to produce IndexOutOfBoundsException:

public class IndexOutOfBoundsExceptionExample {
    public static void main(String[] args) {
        int[] integers = new int[5];
        System.out.println(integers[5]); // Accessing out of range index
    }
}

The above code will result in an IndexOutOfBoundsException because we are trying to access an index that is greater than or equal to the size of the array which is 5.

Handling IndexOutOfBoundsException

In Java, IndexOutOfBoundsException is a runtime exception, which means that it is not mandatory to catch or declare it. However, in larger applications, it is always recommended to handle exceptions to avoid unexpected runtime crashes.

Here is an example of how we can handle this exception in Java:

public class IndexOutOfBoundsExceptionExample {
    public static void main(String[] args) {
        int[] integers = new int[5];
        try {
            System.out.println(integers[5]); // Accessing out of range index
        } catch (IndexOutOfBoundsException e) {
            System.out.println("IndexOutOfBoundsException Catched: " + e.getMessage());
        }
    }
}

In the above code, we have used a try-catch block to handle the IndexOutOfBoundsException. If an exception is thrown in the try block, it is caught and handled in the catch block.

Conclusion

In conclusion, IndexOutOfBoundsException is a runtime exception in Java that occurs when we try to access an index out of range of an array, List or String. We can handle this exception by using a try-catch block, and it is always recommended to handle exceptions to avoid unexpected runtime crashes in larger applications.