trying to pass char array as an argument in java and getting Index error-CodePudding

I'm trying to draw and initialize 2d array, when all my code is in main method there is no error but i split my code to methods and i had index error.

This is my method :

public static void initializeTable(char[][] table ) {

    for (int i = 0; i < row; i  ) {
        for (int j = 0; j < column; j  ) {
             table[i][j] = 'S';   //this is line 90 where the error occurs i think.
        }
    }
}

How i use it in main :

    public class Cinema {
    public static int row, column,x,y;

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        char[][] table = new char[row][column];

        enterRowColumn();
        initializeTable(table); //line 15
    }
}

And error message :

    Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 0 out of bounds for length 0
    at cinema.Cinema.initializeTable(Cinema.java:90)
    at cinema.Cinema.main(Cinema.java:15)

CodePudding user response：

Default value for primitive numbers is 0.

public static int row, column,x,y;

Those all are initialized as zeroes. Then you create array

char[][] table = new char[row][column];

before you assign other values, and array looks like char[0][0].

Move the array initialization after you assign values to row and column

CodePudding user response：

You can avoid the ArrayIndexOutOfBoundsException by iterating using the array's state.

for (int i = 0 ; i < table.length ;   i) {
  for (int j = 0 ; j < table[i].length ;   j) {
    ...
  }
}

However, that still leaves you with the logical error of creating the table before knowing the dimensions. Basically change the order of these operations.

enterRowColumn()
char[][] table = new char[row][column];

p.s. kudos for using methods to do things rather than doing everything in your main method.