Method 3: Modern Elegance with ES6 and Beyond

Step 1: Extract Only the Alphabets

In this method, we're tapping into the powerful arsenal of ES6 methods, specifically map and filter, to craft a more streamlined solution.

Creating an Alphabetic Array

First off, we extract only the alphabetical characters from the string and store them in a new array, which we'll call alphaOnly.

Here's how you can do it in multiple languages:

1List<Character> alphaOnly = str.chars()
2    .mapToObj(c -> (char) c)
3    .filter(c -> Character.toString(c).matches("[a-zA-Z]"))
4    .collect(Collectors.toList());

Step 2: The Transformation Act

After creating our alphaOnly array, the next phase is where the real magic happens. We'll split the original string into an array and perform a transformation using map.

Returning Non-Alphabetic Characters

During this transformation, if a character does not match our Regular Expression criteria (i.e., it's not an alphabetical character), we simply return it in its current position, leaving it untouched.

Picture this as walking through a garden and only flipping the stones that have a specific marking, while leaving all others in their original state.