Declarations, Initialization, and Scoping - SCJP Sun Certified Programmer for Java Platform SE6 - page 94

To instantiate a multidimensional array, you denote the size of each dimension in the
new statement. For example:

7. values = new char[4][3];
8. names = new String[10][5][20];

To access an element in a multidimensional array, specify an index for each dimension.
For example, the following statement stores an 'A' in the fi rst column of the fi rst row of
values , and “George Washington” in the twentieth level of the second column of the fi rst
row of names :

9. values[0][0] = 'A';
10. names[0][1][19] = “George Washington”;

The following nested for loops are typical when working with two-dimensional arrays.
These particular nested loops fi ll the values array with chars starting with ' A '. (Similarly,
you could use three nested loops to iterate through the names array.)

11. char current = 'A';
12. for(int row = 0; row < values.length; row++) {
13. for(int col = 0; col < values[row].length; col++) {
14. values[row][col] = current++;
15. }
16. }

Figure 2.6 shows what the values array looks like in memory. The values array consists
of 4 arrays, each containing 3 chars for a total of 12 chars .

FIGURE 2.6 The values array is a double array of chars .

'A'
'B'
'C'

'D'
'E'
'F'

0
1
2
3

values

'G'
'H'
'I'

A char[][] reference

'J'
'K'
'L'

An array of four
char[] references

Four char arrays