Why would my book say that Integer's compareTo has an Object parameter?

Question

I'm preparing for the AP Computer Science Exam and I'm confused by my text's discussion of the Integer class.

The text defines Integer's compareTo as follows:

 int compareTo(Object other)

It made since to me at first that it would have an Object parameter because I thought that was the only way it could implement Comparable. However, I ended up looking at the Integer class in Eclipse and I noticed that it uses generics for Comparable and thus defines compareTo with an Integer parameter.

Is this a mistake in my book? It led me to believe that it was casting the Object to an Integer in the method, which is wrong (and makes a difference on the exam). Am I missing something here?

Answer 1

That was how the code looked in pre-Java 5 versions, when generics were not there. This also shows that the book you're referring is toooooo old. Please avoid.