Can someone tell me why this if(string1.equals(string2)) instance isn't working properly? (Trying to check for file extensions)

	String extension = ".txt";
	
	if (name1.substring(name1.length()-4).equals(extension))
		name1 += ".txt";

	System.out.println("Enter a second file name: ");
	String name2 = console.nextLine();
	
	if (name2.substring(name2.length()-4).equals(extension))
		name2 += ".txt";

Ninja Edit: It is working, so now the question is how can I say is not equal to?

edit again: I just changed it to

	String extension = ".txt";
	
	if (name1.substring(name1.length()-4).equals(extension) != true)
		name1 += ".txt";

	System.out.println("Enter a second file name: ");
	String name2 = console.nextLine();
	
	if (name2.substring(name2.length()-4).equals(extension) != true)
		name2 += ".txt";

Here's my fully revised code, the next morning:

	//This next section just adds .txt if it is not present, skip down to next comment
	String extension = ".txt";
	
	if (!name1.endsWith(extension))
		name1 += ".txt";
	
	if (!name2.endsWith(extension))
		name2 += ".txt";

	//end .txt check

just in case anyone was wondering

To sum it up: It was working, I just didn't think about what I was actually comparing. I had to make it not equal instead of equals.