Created and added methods to the class Board.java to keep track of permutation states.

src/Assignments/A1/models/Board.java

@@ -18,7 +18,7 @@ public class Board {
      */
     public Board() {
         this.pieces = new Piece[9];
-        for (int index = 1; index <= 9; index++) {
+        for (int index = 1; index < 9; index++) {
             this.pieces[index-1] = new Piece(index-1, index);
         }
     }
@@ -35,11 +35,19 @@ public class Board {
         if (board.length != 9) {
             throw new IllegalArgumentException("The board must be a array size of 9.");
         }
-
         this.pieces = board;
     }
 
-
+    /**
+     * Checks the status of a place on the board. If the location is taken or not.
+     *
+     * @precondition loc >= 0 & loc <= 8
+     * @postcondition none
+     * @param loc the location being checked.
+     *
+     * @return If the location has a piece, True
+     *         If the location is null,     False
+     */
     public boolean isTaken(int loc) {
         if (invalidLocation(loc)) {
             throw new IllegalArgumentException("Invalid location specified. Valid Range: 0 <= Location <= 8");
@@ -48,14 +56,36 @@ public class Board {
     }
 
     /**
-     * Returns the array of pieces.
+     * Returns a value in the array of pieces.
+     *
+     * @precondition loc >= 0 & loc <= 8
+     * @postcondition none
+     * @param loc the location of the desired piece.
+     *
+     * @return the array of pieces.
+     */
+    public Piece getPiece(int loc) {
+        if (invalidLocation(loc)) {
+            throw new IllegalArgumentException("Invalid location specified. Valid Range: 0 <= Location <= 8");
+        }
+        return pieces[loc];
+    }
+
+    /**
+     * Checks and searches for the location of the open location and returns the index.
      *
      * @precondition none
      * @postcondition none
-     * @return the array of pieces.
+     *
+     * @return the location of the empty piece.
      */
-    public Piece[] getPieces() {
+    public int getOpenLocation() {
-        return this.pieces;
+        for (int index = 0; index < 9; index++) {
+            if (this.pieces[index] == null) {
+                return index;
+            }
+        }
+        throw new IllegalStateException("The state of the board must have 1 empty space.");
     }