Quick Answer

Fix incorrect array usage.

Understanding the Issue

Occurs when treating non-array variables as arrays or vice versa. Also happens with incorrect array syntax.

The Problem

This code demonstrates the issue:

Java Error 
String s = "hello";
char c = s[0]; // Error

The Solution

Here's the corrected code:

Java Fixed 
// Correct array usage
String[] arr = {"h","e","l","l","o"};
char c = arr[0].charAt(0);

// String character access
String s = "hello";
char c = s.charAt(0);

// Array declaration syntax
int[] numbers = new int[10]; // Preferred
int numbers[] = new int[10]; // Valid but discouraged

Key Takeaways

Use proper array syntax and type-safe access.