Hi, I got some errors when I try to write a 2d array in processing 1.0.7:

java.lang.ArrayIndexOutOfBoundsException: 4
     at generater.fourDots(generater.java:75)
     at generater.setup(generater.java:33)
     at processing.core.PApplet.handleDraw(PApplet.java:1402)
     at processing.core.PApplet.run(PApplet.java:1327)
     at java.lang.Thread.run(Thread.java:619)

Here's the code:

--------------------------------

int [][] points;

void setup()
{
 size(120,120);
 rect(20,20,80,80);
 for(int i=20;i<=80;i=i+20){
   line(20,i,100,i);
   line(i,100,i,20);
 }
 for(int x=20; x<=100; x=x+20){
   for(int y=20; y<=100; y=y+20){
     ellipse(x, y, 10, 10);
   }
 }
initial();
while (fourDots()!=true){
 randomPoint();
}
}


void initial (){
 for(int x=0; x<5; x++){
   for(int y=0; y<5; y++){
    points [x][y] =0;
   }
 }
}

void randomPoint(){
 int x = int (random(0,5));
 int y = int (random(0,5));
 print(x);
 print(y);
 if( points[x][y] ==0){
   points[x][y] =1;
   fill(0);
   ellipse(20*x,20*y,10,10);  
 }
}

boolean fourDots(){
 boolean value = false;
 int sum=0;
   for(int x=0; x<5; x++){
     for(int y=0; y<5; y++){
       sum=sum+points[x][y];
     }
   }
   if(sum>=4) {
    value= true;}
  return value;
}

Does anyone know what does that error meaning? Thanks~

Thanks a lot~