this vs super, In Depth

What each one means

this refers to the current object — useful to disambiguate a field from a same-named parameter, to pass the current instance elsewhere, or to chain to another constructor with this(...). super refers to the immediate superclass part of the current object — used for super.method() and super(...).

Both together

super.describe() calls the parent's version even though Dog overrides it, letting the child extend rather than fully replace the behaviour.

class Animal {
    protected String name;
    Animal(String name) { this.name = name; }
    String describe() { return "Animal: " + name; }
}
class Dog extends Animal {
    Dog(String name) { super(name); }
    @Override String describe() {
        return super.describe() + " (a dog)";
    }
}

The rules

this(...) and super(...) can each only appear as the first statement of a constructor, and you can never use both in the same one — the object needs exactly one initialization path per constructor.