In my code below, I am experiencing a problem I am unable to get around... when I add a class Person object to an array, it appears to add fine, however when I attempt to print out that object value form a specified array position, it outputs "null."
Here is the code
import java.util.Scanner;
import java.util.Arrays;
import java.lang.String;
public class Main
{
    public static void main(String[] args)
    {
        int ARRAY_LENGTH = 2;
        Scanner in = new Scanner(System.in);
        Person[] Persons;
        Persons = new Person[ARRAY_LENGTH];
        for (int i = 0; i < ARRAY_LENGTH; i++)
        {
            System.out.println("Enter a name to add to the array: ");
            Persons[i] = new Person(in.next());
            System.out.println(Persons[i]);
        }
        Arrays.sort(Persons);
        for (int i = 0; i < ARRAY_LENGTH; i++)
        {
            System.out.println(Persons[i]);
        }
    }
}
&
public class Person implements Comparable<Person>
{
    private String name;
    public Person (String aName)
    {
        String name = aName;
    }
    public String getName()
    {
        return name;
    }
    public int compareTo(Person o)
    {
        Person other = (Person) o;
        if (this.name.equals(o.name))
        {
            return 0;
        }
        if (this.name.compareTo(o.name) < 0)
        {
            return -1;
        }
        return 1;
    }
    @Override
    public String toString()
    {
        return name;
    }
}
 
  
                     
                        
No, it hasn't added null to the array. It's put a reference to a Person object in the array, and when you call toString() on that Person object, it's returning the value of the name field... which is always null, because of this constructor:
public Person (String aName)
{
    String name = aName;
}
That isn't assigning a value to the name field - it's declaring a local variable called name. (I'd expect a decent IDE to issue a warning about that.)
You want:
public Person (String aName)
{
    name = aName;
}
 
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