added captures, movement, legalmoves hover, and basics of game

Board.java

@@ -26,6 +26,28 @@ public class Board {
     board = new Piece[8][8];
   }
 
+  public void capture(Piece capturing, Piece captured) {
+    board[capturing.pos.x][capturing.pos.y] = null;
+    board[captured.pos.x][captured.pos.y] = capturing;
+    capturing.pos.x = captured.pos.x;
+    capturing.pos.y = captured.pos.y;
+  }
+
+  public void move(Piece p, Position posi) {
+    board[p.pos.x][p.pos.y] = null;
+    board[posi.x][posi.y] = p;
+    p.pos = posi;
+    if (p instanceof Pawn) {
+      ((Pawn) p).hasMoved = true;
+    }
+    if (p instanceof King) {
+      ((King) p).hasMoved = true;
+    }
+    if (p instanceof Rook) {
+      ((Rook) p).hasMoved = true;
+    }
+  }
+
   public void draw(Graphics g) {
     for (Piece[] row : board) {
       for (Piece p : row) {
@@ -43,11 +65,17 @@ public class Board {
   }
 
   public Piece getPiece(Position pos) {
-    return this.board[pos.x][pos.y];
+    if (inBounds(pos)) {
+      return this.board[pos.x][pos.y];
+    }
+    return null;
   }
 
   public Piece getPiece(int x, int y) {
-    return this.board[x][y];
+    if (inBounds(new Position(x, y))) {
+      return this.board[x][y];
+    }
+    return null;
   }
 
   public void setPiece(int x, int y, Piece p) {