Adds a Grid class and GridTest class

src/main/java/inf112/fiasko/roborally/objects/Grid.java

@@ -0,0 +1,71 @@
+package inf112.fiasko.roborally.objects;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Grid<K> implements IGrid<K> {
+
+    private int height;
+    private int width;
+    private List<ArrayList<K>> grid = new ArrayList<>();
+
+    /**
+     * Initializes a empty grid
+     * @param height sets the height of the grid
+     * @param width sets the width of the grid
+     */
+    public Grid(int height, int width) {
+        this.height = height;
+        this.width = width;
+        for(int y = 0; y < height; y++) {
+            ArrayList<K> row = new ArrayList<>();
+            for(int x = 0; x < width; x++) {
+                row.add(null);
+            }
+            this.grid.add(row);
+        }
+    }
+
+    /**
+     * Initializes a grid filled with standard tiles.
+     * @param height sets the height of the grid
+     * @param width sets the width of the grid
+     * @param tile gives the TileType the grid is to be filled with
+     */
+    public Grid(int height, int width, K tile) {
+        this.height = height;
+        this.width = width;
+        for(int y = 0; y < height; y++) {
+            ArrayList<K> row = new ArrayList<>();
+            for(int x = 0; x < width; x++) {
+                row.add(tile);
+            }
+            this.grid.add(row);
+        }
+    }
+
+    @Override
+    public int getWidth() {
+        return width;
+    }
+
+    @Override
+    public int getHeight() {
+        return height;
+    }
+
+    @Override
+    public K getElement(int x, int y) throws IllegalArgumentException {
+        if(x >= 0 && x <= width && y >= 0 && y <= height) {
+            return grid.get(y).get(x);
+        }
+        throw new IllegalArgumentException();
+    }
+
+    @Override
+    public void setElement(int x, int y, K element) {
+        if(x >= 0 && x <= width && y >= 0 && y <= height) {
+            grid.get(y).set(x, element);
+        }
+    }
+}

src/main/java/inf112/fiasko/roborally/objects/IGrid.java

@@ -1,4 +1,4 @@
-package inf112.fiasko.roborally.element_properties;
+package inf112.fiasko.roborally.objects;
 
 /**
  * This Interface describes a grid