Quick Answer

Handle invalid array access.

Understanding the Issue

This exception occurs when trying to access an array with an illegal index (negative or ? array length).

The Problem

This code demonstrates the issue:

Java Error 
int[] arr = new int[5];
int val = arr[5]; // Throws

The Solution

Here's the corrected code:

Java Fixed 
// Solution 1: Check bounds before access
int index = 5;
if (index >= 0 && index < arr.length) {
    val = arr[index];
}

// Solution 2: Enhanced for loop
for (int num : arr) {
    // Safe iteration
}

// Solution 3: Use List instead
List<Integer> list = Arrays.asList(1, 2, 3);
if (index < list.size()) {
    val = list.get(index);
}

// Solution 4: Array utility methods
int safeGet(int[] array, int index) {
    return (index >= 0 && index < array.length) ? array[index] : 0;
}

Key Takeaways

Always validate array indices before access.