generic class signature allows to extends the same interface multiple times.
Ideally it should throw compile time here. 

Please find the below code. It compiles successfully. But I think it shouldn't compile it. Class B signature allows to extends the MyInterface<E> twice.

//-- Code start here --
//Test1.java
import java.lang.reflect.*;

public class Test1 {
	public static void main(String[] args) {
		B b = new B<Sun1>();
	}
}

class D { }

interface MyInterface<E> {
	public String foo();
}

class MyClass { }

class Sun1 extends MyClass implements MyInterface<Sun1>, MyInterface<Sun1> {
	public String foo() {
		return "test";
	}
}

class B < E extends MyClass & MyInterface<E> & MyInterface<E> > extends D {
}
//-- code end here