non-static variable this cannot be referenced from a static context

[Timothy Toe]

class NonStaticInner3 {
    //Non-static inner class.
    class NonStaticInner1 {
    }
    
    //If you have static for this method, you'll get error :non-static 
    //variable this cannot be referenced from a static context
    public /*static*/ NonStaticInner1 makeInstance() {
        return new NonStaticInner1();
    }
    public static void main (String args[]) {
        //But non-static variable this is allowed here ?  
        //Which is also a static method / static context.
        String s = new String(); 
    }
}

Why ?

[Keen Chen]

hi
if u wanna a inner class (not static)object, u do this: new.Outer().new Inner(). must need a Outter class object reference first. right?
but , in a static method ,not exist a reference(unless u NEW it).
because static method is pertain a class,