allocating for array and then using constructor

Question

Person.java

public class Person {
    public String firstName, lastName;

    public Person(String firstName,
            String lastName) {
        this.firstN         


        

Answer 1

Person[] people = new Person[20];

only allocates memory for objects Person (filled with nulls). Then you need to fill it with particular Persons (with random name and surname int this example).

Answer 2

Yes, it is correct.

The line:

Person[] people = new Person[20]

allocates the array, full of references to null while the line:

new Person(NameUtils.randomFirstName(),
                      NameUtils.randomLastName());  //this line

fills it [the array] by instantiating objects of type Person, and assigning the reference in the array.

Answer 3

new Person[20] creates an array that can hold 20 references to Person objects. It does not create any actual Person objects.

new Person(...) creates a Person object.

The critical distinction to make here is that unlike in C or C++, new Person[20] does not allocate memory for 20 Person objects. The array does not contain the actual objects; it only contains references to them.