java - How to create and use a two dimensional array of classes -


i experimenting 2 dimensional array of classes in java. wrote following (wrong) code:

public class gameevent {     static int launch_alien = 0;     static int end = 1;      long time;     long cum_time;     int alien_type;     int event_code; }

then

gameevent[][] event_array = new gameevent[max_levels][max_events];

and accessed code below (read comment in code):

event_array[lev][ctr].event_code = code; // nullpointer exception @ runtime

so question is, least painful way change code works.

gameevent[][] event_array = new gameevent[max_levels][max_events];

this allocates array of references gameevent objects not objects themselves.

to allocate obects necessary every cell of array:

for (int = 0; < max_levels; ++i)   (int j = 0; j < max_events; ++j)     event_array[i][j] = new gameevent();

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