Language: Java I'd like for my code to print "O" 30% of the time, but it prints "O" 100% of the time. How can I fix that?

Code:

public class PetriDish {
private boolean[][] grid;

public PetriDish()
{
// Formula: (int)(Math. random() * (max - min + 1) + min);
int row = (int)(Math. random() * (30 - 5 + 1) + 5);
int column = (int)(Math. random() * (30 - 5 + 1) + 5);
boolean[][] grid2 = new boolean [row][column];
for(int i = 0; i < row; i++)
{
for(int j = 0; j < column; j++)
{

grid2[i][j] = Math. random() < 0.30;
}
}
grid = grid2;
}

public void showGrid()
{
for(int row = 0; row < grid. length; row++)
{
for(int column = 0; column < grid[0].length; column++)
{
if (grid[row][column] = true)
System. out. print("O"); //true state
else
System. out. print("."); //False State
}
System. out. println();
}

}

public int numNeighbors(int row, int col)
{
int count = 0;
for(int i = row - 1; i <= row + 1 ; i++)
{
for(int j = col - 1; j <= col + 1; j++)
{
if ((i >= 0) && (i < grid. length))
{
if ((j >= 0) && (j < grid. length))
{
if ((i != row ) && (j != col))
{
if (grid[i][j] = true)
count++;

}
}
}
}
}
return count;
}

public static void main(String args[])
{
PetriDish p = new PetriDish();
p. showGrid();
/*Change the (4,4) to be a random valid value within the grid*/
System. out. println(p. numNeighbors(0,0));
}
}

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