The following is a short sketch with a single new Class. In the class I’m trying to develop a 2D array in the Constructor and then use it in a method in the class. The method recognizes a variable in the constructor but does not recognize any of the elements in the 2D array? It works if you comment …

Sorry … I used the wrong verbiage. You need to allocate them in the constructor using the new keyword. class Level { boolean[][] my2dArr; // declare Level(int arg1, int arg2) { my2dArr = new boolean[arg1][arg2]; // allocate my2dArr[0][0] = true; // define }

Using a 2D Array in a Class Object - NullPointerException?

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RetProf June 6, 2020, 12:07am 8

If I remove the declaration in the constructor, there is a NullPointerException as it attempts to define the values of the variables in the array.

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Using a 2D Array in a Class Object - NullPointerException?

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