Java - Populating an ArrayList gives null pointer error

Question

In my class I define:

private ArrayList<BlockObject> blocks;

And later:

blocks.add(new BlockObject(x, y));

However I get this error

02-22 17:06:52.672: E/AndroidRuntime(479): Caused by: java.lang.NullPointerException
02-22 17:06:52.672: E/AndroidRuntime(479):  at com.comp1008.hhh.uuu.Scenario.blocks(Scenario.java:41)

Any suggestion?

Adrian Jandl · Accepted Answer · 2013-02-22 17:02:21Z

7

private ArrayList<BlockObject> blocks = new ArrayList<BlockObject>();

You have to initialize your object.

answered Feb 22, 2013 at 17:02

Adrian Jandl

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1 Comment

piggyback Over a year ago

Oh man, that was blazing fast and amazingly easy. I am new to the language, very much appreciated

PermGenError · Accepted Answer · 2013-02-22 17:02:14Z

5

you have to initialize your arraylist before you populate it.

private ArrayList<BlockObject> blocks = new ArrayList<BlockObject>();

answered Feb 22, 2013 at 17:02

PermGenError

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