RAM and ROM perplexing scenarios

I'm now researching the differences between RAM (Random Access Memory) and ROM (Read-Only Memory), however I've come across several baffling circumstances that have left me wanting clarity. Here's a code example that demonstrates my areas of uncertainty:

// Code Snippet 1 (Java)
public class Main {
    public static void main(String[] args) {
        int[] ramArray = new int[5];
        for (int i = 0; i < 5; i++) {
            ramArray[i] = i;
        }
        System.out.println("Data stored in RAM: " + ramArray[5]);
    }
}

Here are the specific issues I'm seeking assistance with:

1. Despite initializing an array in RAM with a size of 5 elements, I encountered unexpected behavior when attempting to access the sixth element ramArray[5] outside the array bounds. Can you explain why this code results in an ArrayIndexOutOfBoundsException, and how does RAM handle such errors?

2. While experimenting with Java, I encountered unexpected results when attempting to print the value of ramArray[5] using System.out.println(). Despite expecting an error due to accessing an out-of-bounds index, I'm unsure about the underlying mechanism responsible for handling this situation in RAM. Could you provide insights into how RAM manages memory access violations?

3. I'm confused about the distinctions between RAM and ROM, particularly in terms of memory storage capacity and data accessibility. Could you explain the contrasts between the two forms of memory and offer instances to demonstrate the differences?

4. While learning Java from this source, I faced difficulties understanding topics such as memory allocation and data retrieval in RAM. What are the differences between RAM and ROM, and what do they mean for developers working on memory-intensive applications?

Your experience and help would be highly welcomed as I work through these complexities and gain a better grasp of RAM and ROM. Thank you for your help.