Refactor greeting logic in HelloApp

[HarryDebugs]

No description provided.

[Copilot]

Pull request overview

Refactors HelloApp greeting output to support greeting multiple provided names instead of only the first CLI argument.

Changes:

• Inverts the argument check to handle the no-args case first (Hello, World!).
• Builds a comma-separated list of all CLI args and prints them in the greeting.

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[Copilot]

There appears to be trailing whitespace on the blank lines in this block (e.g., the empty lines after new StringBuilder(); and after the loop). Please remove trailing spaces to avoid unnecessary diffs and potential style/lint failures.

Suggested change

	for (String name : args) {
	nameBuilder.append(name).append(", ");
	}
	for (String name : args) {
	nameBuilder.append(name).append(", ");
	}

[Copilot]

In the else branch, if (nameBuilder.length() > 0) is redundant because this code path already implies args.length > 0. Also building with a trailing ", " then trimming via substring is harder to read and does extra work; consider String.join(", ", args) or StringJoiner to avoid the trim step.

Suggested change

	StringBuilder nameBuilder = new StringBuilder();
	for (String name : args) {
	nameBuilder.append(name).append(", ");
	}
	if (nameBuilder.length() > 0) {
	String names = nameBuilder.substring(0, nameBuilder.length() - 2);
	System.out.println("Hello, " + names + "!");
	}
	String names = String.join(", ", args);
	System.out.println("Hello, " + names + "!");