Draft: Resolve "Errors"

Closes #1 (closed)

src/main/java/dotsandboxes/DotsAndBoxesGrid.java

@@ -3,6 +3,7 @@ package dotsandboxes;
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Observer;
 import java.util.function.Consumer;
 
 /**
@@ -113,6 +114,11 @@ public class DotsAndBoxesGrid {
         // A box is complete if the north and south horizontals and the east and west verticals have all been drawn.
         // FIXME: You'll need to fix this code (after writing a test first).
         return true;
+        if (this.horizontals[x][y] && this.horizontals[x + 1][y] && this.verticals[x][y] && this.verticals[x][y + 1])
+        {
+        return true;
+        }
+            else return false;
     }
 
     /** Tries to claim a box for a player. If the box is complete, sets the ownership and returns true. */
@@ -139,7 +145,9 @@ public class DotsAndBoxesGrid {
             throw new IndexOutOfBoundsException(String.format("y was %d, which is out of range. Range is 0 to %d", y, height));
         }
 
-        // FIXME: You need to throw an exception if the line was already drawn.
+        if (this.horizontals[x][y]) {
+            throw new IllegalStateException("Line already drawn");
+            }
 
         this.horizontals[x][y] = true;
 
@@ -170,7 +178,9 @@ public class DotsAndBoxesGrid {
             throw new IndexOutOfBoundsException(String.format("y was %d, which is out of range. Range is 0 to %d", y, height - 1));
         }
 
-        // You need to throw an exception if the line was already drawn.
+        if (this.verticals[x][y]) {
+            throw new IllegalStateException("Line already drawn");
+            }
 
         this.verticals[x][y] = true;
         // Try to claim the north or south boxes