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Full Stack JavaScript Techdegree Student 102 PointsWhat is the "new anonymous class" said at 4min 27seconds of the video?
Instructor said "Making a brand new anonymous class from this interface & overriding the 1 abstract method that needed be completed (the compare method)". What exactly is this anonymous class, and which line is it at? Thank you
1 Answer
Michael Kobela
Full Stack JavaScript Techdegree Graduate 19,570 PointsFrom the code in Main.java, the anonymous class is the one created with "new Comparator<Book>()". It's anonymous because you never store the class in a local property, it's just passed into the sort method. See example below that makes an non anonymous class The Comparator interface has an abstract method compare which this code is overriding.
// anonymous example
Collections.sort(books, new Comparator<Book>() {
@Override
public int compare(Book b1, Book b2) {
return b1.getTitle().compareTo(b2.getTitle());
}
});
// not anonymous example
Comparator myComparator = new Comparator<Book>() {
@Override
public int compare(Book b1, Book b2) {
return b1.getTitle().compareTo(b2.getTitle());
}
}
Java docs: https://docs.oracle.com/javase/8/docs/api/java/util/Comparator.html