对对象的引用（通过 3 个类）

Question

I have a classes:

class A{
// represents the fields
}

class B{
A objA = new A();
// assigning a values to an object (objA) of class A
}

class C{
//I need this object (objA) with assigned values in the class B to calculations in class C 
}

How to pass (references?) to the class C? Or if there is a better way to thank you in advance for your help. Singleton is not an option.

I need to use object (objA) in class C.

Answer 1

Expand your class B to something like:

public class B {
    private A objA = new A();

    public B() {
        objA.setA(4);
    }

    public A getObjA() {
        return objA;
    }
}

And class C should take a reference of A in its constructor like:

public class C {
    private A objA;

    public C(A objA) {
        this.objA = objA;
    }

    public A getObjA() {
        return objA;
    }
}

then in your main you can call:

public static void main(String[] args) {
    B bObj = new B();
    C cObj = new C(b.getObjA());

    System.out.println(cObj.getObjA().getA());
}

Now the object class C , cObj contains the same reference of class A object like the one in bObj