How can I access the outer class instance of a non-this instance of nested class in Java?

Question

I'm familiar with the ClassName.this syntax to access the outer class instance of the current instance in the lexical scope of a nested inner class. What is the syntax to access the outer class instance of another instance?

For example, consider the following types:

public class A {
    public int fieldA;

    private class B {
        public int fieldB;

        public void foo(A.B other) {
            /* Hypothetical code goes here... */
        }
    }
}

Inside B#foo, I know I can use the syntax A.this.fieldA to access the current instance's outer instance's field fieldA. How do I access the same information for other (e.g., something like other.B.this.fieldA)?

I know I can add an instance method (e.g., getOuterInstance) to B that simply returns A.this, which would let me call other.getOuterInstance() in the above example. However, I'm hoping there's some built-in syntax I'm just not aware of.