Using a 2-dimensional object array

Question

This is my 2-dimensional array:

String[][] theMaze = new String[row][column];

How to use it in this method?

public void ruteToX(String[][] theMaze){
    // call theMaze and process in this method
}

yes, mr. mathew. that's array filled with value in main. And than how to call that array already filled in method ruteToX? — Wisnu, Mar 15 '16 at 15:59

score 1 · Accepted Answer · answered Mar 15 '16 at 15:47

Assuming I understood your question in the right sense.

I'll show you an example of passing an array to the method ruteToX(...).

public class Example
{

String[][] theMaze = new String[5][5];
public void ruteToX(String[][] theMaze)
{ 
//call theMaze and process in this method 
}

public static void main(....)
{
   Example ob=new Example();
   ob.ruteToX(ob.theMaze);
   //passed the value of reference or the pointer to the function ruteToX(...)
}
}

How is it passed?

When you pass an array, the value of it's pointer or reference in the memory is passed which means if you make any changes to the parameter array in the method, the actual array will also face the same changes (since they are the same-same reference).

score -3 · Answer 2 · answered Mar 15 '16 at 15:45

-3

When passing in the array, in the previous method (whatever is running before 'ruteToX') call the method and pass the array in using just the variable name.

 public void previousMethod(){
   ruteToX(theMaze);
}    

public void ruteToX(String[][] theMaze){
    // call theMaze and process in this method
}

EDIT: In addition, once in the method you can either use the array as is or create a new array equal to the original array.

public void ruteToX(String[][] theMaze){
        String[][] secondMaze = theMaze; 
    }

answered Mar 15 '16 at 15:45

AnthonyGordon

27
4

I don't agree with `create a new array equal to the original array`. – Mathews Mathai Mar 15 '16 at 15:51
@MathewsMathai agreed it is not an good decision in a good amount of examples however I wanted to offer more than one option. – AnthonyGordon Mar 15 '16 at 16:02
It's not about decision. ` String[][] secondMaze = theMaze;` doesn't creat a new array. the new array object you have created has the same reference since you are using `=`. – Mathews Mathai Mar 15 '16 at 16:04
And so if yoh make a change to `secondMaze`, the original array will also face the same change. – Mathews Mathai Mar 15 '16 at 16:05
You could use `Arrays.copyOf()` or `theMaze.clone()` to create a new array with the same values as the original array. – Mathews Mathai Mar 15 '16 at 16:06

Using a 2-dimensional object array

2 Answers2