Java generics compile in Eclipse, but not in javac

Question

I had to discover I have Java code in my project, which compiles and runs fine in Eclipse, but throws a compilation error in javac.

A self-contained snippet:

Answer 1

I know it's old question, but I want to mention, the function could be written as:

import java.util.HashSet;
import java.util.Set;

public class Main {

public static void main(String[] args) {
        Set setOfInts = new HashSet();
        Set