CODEWITHSUNDEEP
java
user2661167
user2661167

Reputation: 491

Call function from calling object

This is for a personal project. Not assignment or work. Say I have an object, objA that has a function callB().

When I run callB() it calls a function in object B. The function in objB can have calls to functions in objA.

Eg. objA calls callB().
Inside callB() there is a function like setObjAName() which sets a variable on objA.

How would I do this in Java? How do I reference objA from objB?

Upvotes: 0

Views: 67

Answers (1)

Davis Broda
Davis Broda

Reputation: 4125

The simplest method is to simply pass a reference to A in with the method call, which will allow for B to access any of A's public methods. 

public class ClassA {

    public String someAVar;

    public void callB(ClassA a){
        //do stuff
        ClassB b = new ClassB();
        b.setObjA(this,"newValue");
    }
}
public class ClassB{
    public void setObjA(ClassA A, String newValue){
        A.someAVar = newValue;
    }
}

Alternatively you might want the variable to be settable without passing in a particular instance, in which case static methods and variables are your friend.

public class ClassA {

    public static String someAVar;

    public void callB(){
        //do stuff
        ClassB b = new ClassB();
        b.setObjA("newValue");
    }
}


public class ClassB{
    public void setObjA(String newValue){
        ClassA.someAVar = newValue;
    }
}

Upvotes: 1

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