Make Point and its subclasses more consistent

Author: JasperGeurtz

src/main/java/bwapi/Point.java

@@ -1,13 +1,13 @@
 package bwapi;
 
-class Point implements Comparable<Point>{
+public abstract class Point<T extends Point> implements Comparable<Point>{
     static final int TILE_WALK_FACTOR = 4; // 32 / 8
 
     public final int x;
     public final int y;
     private final int scalar;
 
-    Point(final int x, final int y, final int type) {
+    protected Point(final int x, final int y, final int type) {
         this.x = x;
         this.y = y;
         this.scalar = type;
@@ -29,9 +29,9 @@ public String toString() {
         return "[" + x + ", " + y + "]";
     }
 
-    protected double getDistance(final int x, final int y) {
-        final int dx = x - this.x;
-        final int dy = y - this.y;
+    public double getDistance(T point) {
+        final int dx = point.x - this.x;
+        final int dy = point.y - this.y;
         return Math.sqrt(dx * dx + dy * dy);
     }
 
@@ -52,10 +52,17 @@ private static int getApproxDistance(final int x1, final int y1, final int x2, f
         return (minCalc >> 5) + minCalc + max - (max >> 4) - (max >> 6);
     }
 
-    public int getApproxDistance(final Point point) {
+    public int getApproxDistance(final T point) {
         return getApproxDistance(x, y, point.x, point.y);
     }
 
+    public abstract T subtract(T other);
+
+    public abstract T add(T other);
+
+    public abstract T divide(int divisor);
+
+    public abstract T multiply(int multiplier);
 
     @Override
     public boolean equals(Object o) {

src/main/java/bwapi/Position.java

@@ -1,7 +1,7 @@
 package bwapi;
 
 
-public class Position extends Point {
+public class Position extends Point<Position> {
 
     public static final int SIZE_IN_PIXELS = 1;
     public static final Position Invalid = new Position(32000 / SIZE_IN_PIXELS, 32000 / SIZE_IN_PIXELS);
@@ -40,12 +40,4 @@ public Position divide(final int divisor) {
     public Position multiply(final int multiplier) {
         return new Position(x * multiplier, y * multiplier);
     }
-
-    public double getDistance(final Position position) {
-        return getDistance(position.x, position.y);
-    }
-
-    public int getApproxDistance(Position position) {
-        return super.getApproxDistance(position);
-    }
 }

src/main/java/bwapi/TilePosition.java

@@ -1,6 +1,6 @@
 package bwapi;
 
-public class TilePosition extends Point {
+public class TilePosition extends Point<TilePosition> {
 
     public static final int SIZE_IN_PIXELS = 32;
     public static final TilePosition Invalid = new TilePosition(32000 / SIZE_IN_PIXELS, 32000 / SIZE_IN_PIXELS);
@@ -39,8 +39,4 @@ public TilePosition divide(final int divisor) {
     public TilePosition multiply(final int multiplier) {
         return new TilePosition(x * multiplier, y * multiplier);
     }
-
-    public double getDistance(final TilePosition position) {
-        return getDistance(position.x, position.y);
-    }
 }

src/main/java/bwapi/WalkPosition.java

@@ -1,6 +1,6 @@
 package bwapi;
 
-public class WalkPosition extends Point {
+public class WalkPosition extends Point<WalkPosition> {
 
     public static final int SIZE_IN_PIXELS = 8;
     public static final WalkPosition Invalid = new WalkPosition(32000 / SIZE_IN_PIXELS, 32000 / SIZE_IN_PIXELS);
@@ -35,8 +35,4 @@ public WalkPosition divide(final int divisor) {
     public WalkPosition multiply(final int multiplier) {
         return new WalkPosition(x * multiplier, y * multiplier);
     }
-
-    public double getDistance(final WalkPosition position) {
-        return getDistance(position.x, position.y);
-    }
 }

src/test/java/bwapi/PointTest.java

@@ -20,4 +20,13 @@ public void pointEqualsTest() {
 
 		assertNotEquals(new TilePosition(1, 1), null);
 	}
+
+	@Test
+	public void pointDistanceAccesibleTest() {
+		TilePosition tp = TilePosition.Origin;
+
+		assertEquals(0, tp.getApproxDistance(tp));
+		assertEquals(0, tp.getDistance(tp), 0.001);
+		assertEquals(0 , tp.getLength(), 0.001);
+	}
 }