Assign value to an array object in Java

Question

I am attempting to assign a value to an array object like this:

public class Players {
    String Name;
}

Players[] player = new Players[10];
String name = Mike;
player[1].Name = name;

I am getting a NullPointerException and am not sure why. What could be causing this?

This class should really be named Player, since each instance is only one player.. — Brendan Long
– Brendan Long, Commented May 14, 2012 at 3:04
Thanks for the suggestion. I think will change the class to player and the array to players — user1392897
– user1392897, Commented May 14, 2012 at 3:11

Sergey Kalinichenko · Accepted Answer · 2012-05-14 03:02:37Z

9

This is because creating a new array does not create individual objects inside the array; you should be creating them separately, e.g. in a loop.

Players[] player = new Players[10];
for (int i = 0 ; i != player.length ; i++) {
    player[i] = new Players();
}

answered May 14, 2012 at 3:02

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2 Comments

I understand what you are saying in concept but not implementation. Could you please give an example?

Wow thank you. I didn't realize the objects were not created by initializing the array

QuantumMechanic · Accepted Answer · 2012-05-14 03:02:39Z

4

new Players[10] makes an array with 10 slots. It doesn't put anything in the slots. So all 10 elements of the array are null.

You need to create the objects and stick them into the array. For example:

for (int i = 0; i < player.length; i++) {
    player[i] = new Players();
}

answered May 14, 2012 at 3:02

QuantumMechanic

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