How do I create an array of references to a class , and store the reference-to values for several other objects in array?

Question

For example, I have this code with these classes. How do i Create an array of references to a class , and store the reference-to values for several other objects like a1 or a2 if created?

    public abstract class Test1 {
    // Instance field vars

    public Test(){
    //initializations
    }

    public void method1(){
    //do's
    }

    @override
    public String toString(){
    return (string content)
    }
}

then I have another similar class

    public class Test2 extends Test1 {
    // Instance field vars

    public Test2(){
    //initializations
    }

    public void method2(){
    //do's
     super.method1();
    }

    @override
    public String toString(){
    return super.toString+(string content)
    }
    }

then, my main is something like this

        Test1 a1 = new Test2()
    System.out.println(a1.toString());
    a1.method1();

Answer 1

How about this: -

Test1 [] arrayOfReferences = new Test1[10];

This can store the 10 references of type Test1 and you can populate the array with all of the concrete implementations of abstract class Test1 like new Test2()

Answer 2

There is nothing should stop you using ArrayList<Test1> .

List<Test1> myArr = new ArrayList<>();
myArr.add(new Test2());
myArr.get(0);

Or,

 Test1 a1[] = new Test2[10];
   a1[0] = new Test2();

Learn about inheritance to understand super class and subclass relationship.