7.9 Can a function return an array?

A. Introduction

A function can take a 1-D or 2-D array as input and manipulate the data elements. Once the function finishes processing, how to return the new array back to the caller?

B. How to reflect a 2-D array vertically as shown below? i.e. turn A into B by moving the top row to the bottom, 2nd row to the 2nd but last... etc?

class Reflect2DArray {  
    public static int[][] verticalReflect(int[][] arrayX){
            // Swap rows up and down
    int[][] temp = new int[arrayX.length][arrayX[0].length];
	 for (int row = 0; row < arrayX.length; row++)
		for (int col = 0; col < arrayX[0].length; col++)
			temp[arrayX.length - row -1][col] = arrayX[row][col];
    return temp;
  }
  
  public static void print2DArray(int[][] arrayX){
    for(int[] s:arrayX){
      for(int sp: s)
        System.out.print(sp + " ");
    	System.out.println();
    }
  }
  
  public static void main(String[] args) {
    int[][] speed =   {  {99, 42, 74, 83, 100}, {90, 91, 72, 88, 95},{88, 61, 74, 89, 96}, {61, 89, 82, 98, 93}, {93, 73, 75, 78, 99},{50, 65, 92, 87, 94}, {43, 98, 78, 56, 99}  };
    int[][] vReflect = verticalReflect(speed);
    print2DArray(speed);
    print2DArray(vReflect);
  }
}

C. Try:

Create a function that rotates the elements of a 1-D array by one position, moving the initial element to the end of the array, as shown at right.