3 dimentional array how to get length of z axis

I'm not quite sure what question you're asking.  If all 3 are working, what is the problem?

Those methods will work depending on exactly how the 3 dimensional array is created (there are some choices).

What are the 3 dimensions of the array, and which is z?

If the the array is indexed as data[x][y][z], and data.length is at least 1, and data[0].length is at least 1, then I would use data[0][0].length
if data[0].length is greater than 2, then data[0][1].length and data[0][2].length could also work

data[x][y][z]

any option to get all three lenghts(x, y and z axis lengths) using all 3 set of brackekes(first set[] , second set [], third set []) next to data to be consistent and easy to understand as below similar to how we get individual cell element.

1 2 3 4 5
9 8 7 6 5
1 3 5 7 9
3 5 6 7 8

data[x][][].length--->gives lenght of x axis elements( 4 in above case)
data[][y][].length--->gives lenght of x axis elements( 5 in above case)
data[][][z].length--->gives lenght of x axis elements( no symmetric prism example i can draw here)

 not sure on  non symmetric examples like below where number of row element length varying from each row but i still fee data[x][][].length should give 3 as there are three rows eventhough second row only has 3 elements compared to first row which has 5 elements)
1 2 3 4 5
9 8 7
1 3 5 7 9 2 4 6 8 0

As for the non symmetric example, this is what the various length fields would return...

data.length = 3               // Since there are 3 rows

data[0].length = 5          // Since there are 5 elements in the first row (row 0)
data[1].length = 3          // Since there are 3 elements in the second row (row 1)
data[2].length = 10       // Since there are 10 elements in the third row (row 2)

Hopefully the above demonstrates why your idea of data[x][][].length (and the others) would not make much sense and why you need to be able to explicitly ask for which .length value that you want to query.

data[x][][].length

is not valid syntax

 data[x].length
returns a value only when x <  data.length

data[][y][].length

is not valid syntax

  data[x][y].length
returns a value only when  x <  data.length && y < data[x].length

 data[x][y].length
returns a value only when  x <  data.length && y < data[x].length

can you please elaborate on above

  data[1][1].length what it returns
  data[1][2].length what it returns
  data[0][1].length what it returns


for below non symmetric example

1 2 3 4 5
9 8 7
1 3 5 7 9 2 4 6 8 0

please advise

String[][] data = {
    {"1", "two", "3", "4", "5"},
    {"9", "8", "7"},
    {"1", "3", "5", "7", "9", "2", "4", "6", "8", "0"}
};
      System.out.println("data[1][1] is \"" + data[1][1] + "\"");
      System.out.println("data[1][1].length() is " + data[1][1].length());
      System.out.println("data[1][2] is \"" + data[1][2] + "\"");
      System.out.println("data[1][2].length() is " + data[1][1].length());
      System.out.println("data[0][1] is \"" + data[0][1] + "\"");
      System.out.println("data[0][1].length() is " + data[0][1].length());

data[1][1] is "8"
data[1][1].length() is 1
data[1][2] is "7"
data[1][2].length() is 1
data[0][1] is "two"
data[0][1].length() is 3

data[0][1] is "two"
data[0][1].length() is 3

This one is interesting and makes sense now.
Can there be a another array or arraylist in place of string "two" . Please advise