diff --git a/vtm-tests/test/org/oscim/tiling/source/OkHttpEngineTest.java b/vtm-tests/test/org/oscim/tiling/source/OkHttpEngineTest.java
index d97aef2c..45ff6b89 100644
--- a/vtm-tests/test/org/oscim/tiling/source/OkHttpEngineTest.java
+++ b/vtm-tests/test/org/oscim/tiling/source/OkHttpEngineTest.java
@@ -14,7 +14,6 @@ import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
-import java.net.URL;
 
 import static org.fest.assertions.api.Assertions.assertThat;
 
@@ -30,7 +29,7 @@ public class OkHttpEngineTest {
 		server = new MockWebServer();
 		server.enqueue(mockResponse);
 		server.play();
-		engine = new OkHttpEngine(server.getUrl("/tiles/vtm"));
+		engine = (OkHttpEngine) new OkHttpEngine.OkHttpFactory().create();
 	}
 
 	@After
@@ -50,7 +49,7 @@ public class OkHttpEngineTest {
 
 	@Test
 	public void sendRequest_shouldAppendXYZToPath() throws Exception {
-		engine.sendRequest(new OSciMap4TileSource("http://www.example.org/tiles/vtm"),
+		engine.sendRequest(new OSciMap4TileSource(server.getUrl("/tiles/vtm").toString()),
 				new Tile(1, 2, new Integer(3).byteValue()));
 
 		RecordedRequest request = server.takeRequest();
@@ -59,7 +58,7 @@ public class OkHttpEngineTest {
 
 	@Test
 	public void read_shouldReturnResponseStream() throws Exception {
-		engine.sendRequest(new OSciMap4TileSource("http://www.example.org/tiles/vtm"),
+		engine.sendRequest(new OSciMap4TileSource(server.getUrl("/tiles/vtm").toString()),
 				new Tile(1, 2, new Integer(3).byteValue()));
 
 		InputStream responseStream = engine.read();
@@ -69,7 +68,7 @@ public class OkHttpEngineTest {
 
 	@Test(expected = IOException.class)
 	public void close_shouldCloseInputStream() throws Exception {
-		engine.sendRequest(new OSciMap4TileSource("http://www.example.org/tiles/vtm"),
+		engine.sendRequest(new OSciMap4TileSource(server.getUrl("/tiles/vtm").toString()),
 				new Tile(1, 2, new Integer(3).byteValue()));
 		engine.close();
 
@@ -80,7 +79,7 @@ public class OkHttpEngineTest {
 
 	@Test(expected = IOException.class)
 	public void requestCompleted_shouldCloseInputStream() throws Exception {
-		engine.sendRequest(new OSciMap4TileSource("http://www.example.org/tiles/vtm"),
+		engine.sendRequest(new OSciMap4TileSource(server.getUrl("/tiles/vtm").toString()),
 				new Tile(1, 2, new Integer(3).byteValue()));
 		engine.requestCompleted(true);
 
diff --git a/vtm-tests/test/org/oscim/tiling/source/UrlTileSourceTest.java b/vtm-tests/test/org/oscim/tiling/source/UrlTileSourceTest.java
index b708cb40..395738c6 100644
--- a/vtm-tests/test/org/oscim/tiling/source/UrlTileSourceTest.java
+++ b/vtm-tests/test/org/oscim/tiling/source/UrlTileSourceTest.java
@@ -1,7 +1,5 @@
 package org.oscim.tiling.source;
 
-import com.squareup.okhttp.OkHttpClient;
-
 import org.junit.Before;
 import org.junit.Test;
 import org.oscim.tiling.ITileDataSource;
@@ -29,7 +27,7 @@ public class UrlTileSourceTest {
 
 	@Test
 	public void shouldUseCustomHttpEngine() throws Exception {
-		tileSource.setHttpEngine(new OkHttpEngine(tileSource.getUrl()));
+		tileSource.setHttpEngine(new OkHttpEngine.OkHttpFactory());
 		TestTileDataSource dataSource = (TestTileDataSource) tileSource.getDataSource();
 		assertThat(dataSource.getConnection()).isInstanceOf(OkHttpEngine.class);
 	}
diff --git a/vtm-tests/test/org/oscim/tiling/source/bitmap/BitmapTileSourceTest.java b/vtm-tests/test/org/oscim/tiling/source/bitmap/BitmapTileSourceTest.java
index 34f87ce5..f0f93560 100644
--- a/vtm-tests/test/org/oscim/tiling/source/bitmap/BitmapTileSourceTest.java
+++ b/vtm-tests/test/org/oscim/tiling/source/bitmap/BitmapTileSourceTest.java
@@ -6,7 +6,9 @@ import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mockito;
 import org.oscim.tiling.ITileDataSource;
-import org.oscim.tiling.source.OkHttpEngine.OkHttpFactory;
+import org.oscim.tiling.source.HttpEngine;
+import org.oscim.tiling.source.LwHttp;
+import org.oscim.tiling.source.OkHttpEngine;
 import org.oscim.tiling.source.UrlTileDataSource;
 
 public class BitmapTileSourceTest {
@@ -14,7 +16,7 @@ public class BitmapTileSourceTest {
 
 	@Before
 	public void setUp() throws Exception {
-		tileSource = new TestBitmapTileSource("http://tile.openstreetmap.org", 0, 18);
+		tileSource = new BitmapTileSource("http://tile.openstreetmap.org", 0, 18);
 	}
 
 	@Test
@@ -24,8 +26,8 @@ public class BitmapTileSourceTest {
 
 	@Test
 	public void shouldUseLwHttp() throws Exception {
-		LwHttpFactory lwHttp = Mockito.mock(LwHttpFactory.class);
-		tileSource.setHttpEngine(lwHttp);
+		LwHttp lwHttp = Mockito.mock(LwHttp.class);
+		tileSource.setHttpEngine(new TestHttpFactory(lwHttp));
 		ITileDataSource dataSource = tileSource.getDataSource();
 		dataSource.destroy();
 		Mockito.verify(lwHttp).close();
@@ -33,16 +35,26 @@ public class BitmapTileSourceTest {
 
 	@Test
 	public void shouldUseOkHttp() throws Exception {
-		OkHttpFactory okHttp = Mockito.mock(OkHttpFactory.class);
-		tileSource.setHttpEngine(okHttp);
+		OkHttpEngine okHttp = Mockito.mock(OkHttpEngine.class);
+		tileSource.setHttpEngine(new TestHttpFactory(okHttp));
 		UrlTileDataSource dataSource = (UrlTileDataSource) tileSource.getDataSource();
 		dataSource.destroy();
-		//Mockito.verify(dataSource.mConn).close();
+		Mockito.verify(okHttp).close();
 	}
 
-	class TestBitmapTileSource extends BitmapTileSource {
-		public TestBitmapTileSource(String url, int zoomMin, int zoomMax) {
-			super(url, zoomMin, zoomMax);
+	/**
+	 * Test factory that allows the specific {@link HttpEngine} instance to be set.
+	 */
+	class TestHttpFactory implements HttpEngine.Factory {
+		final HttpEngine engine;
+
+		public TestHttpFactory(HttpEngine engine) {
+			this.engine = engine;
+		}
+
+		@Override
+		public HttpEngine create() {
+			return engine;
 		}
 	}
 }
diff --git a/vtm-tests/test/org/oscim/tiling/source/oscimap4/OSciMap4TileSourceTest.java b/vtm-tests/test/org/oscim/tiling/source/oscimap4/OSciMap4TileSourceTest.java
index 711cd310..060d0c77 100644
--- a/vtm-tests/test/org/oscim/tiling/source/oscimap4/OSciMap4TileSourceTest.java
+++ b/vtm-tests/test/org/oscim/tiling/source/oscimap4/OSciMap4TileSourceTest.java
@@ -4,6 +4,7 @@ import org.junit.Before;
 import org.junit.Test;
 import org.mockito.Mockito;
 import org.oscim.tiling.ITileDataSource;
+import org.oscim.tiling.source.HttpEngine;
 import org.oscim.tiling.source.LwHttp;
 import org.oscim.tiling.source.OkHttpEngine;
 
@@ -25,7 +26,7 @@ public class OSciMap4TileSourceTest {
 	@Test
 	public void shouldUseLwHttp() throws Exception {
 		LwHttp lwHttp = Mockito.mock(LwHttp.class);
-		tileSource.setHttpEngine(lwHttp);
+		tileSource.setHttpEngine(new TestHttpFactory(lwHttp));
 		ITileDataSource dataSource = tileSource.getDataSource();
 		dataSource.destroy();
 		Mockito.verify(lwHttp).close();
@@ -34,9 +35,25 @@ public class OSciMap4TileSourceTest {
 	@Test
 	public void shouldUseOkHttp() throws Exception {
 		OkHttpEngine okHttp = Mockito.mock(OkHttpEngine.class);
-		tileSource.setHttpEngine(okHttp);
+		tileSource.setHttpEngine(new TestHttpFactory(okHttp));
 		ITileDataSource dataSource = tileSource.getDataSource();
 		dataSource.destroy();
 		Mockito.verify(okHttp).close();
 	}
+
+	/**
+	 * Test factory that allows the specific {@link HttpEngine} instance to be set.
+	 */
+	class TestHttpFactory implements HttpEngine.Factory {
+		final HttpEngine engine;
+
+		public TestHttpFactory(HttpEngine engine) {
+			this.engine = engine;
+		}
+
+		@Override
+		public HttpEngine create() {
+			return engine;
+		}
+	}
 }