#850 should fix resource leaks related to gemf files, offline archives and the demo app. adds some test files sources from US national aviation charts at zoom 4

.travis.yml

@@ -104,6 +104,9 @@ before_script:
   - adb shell chmod 777 /mnt/sdcard
   - adb shell mkdir /sdcard/osmdroid/
   - adb push world.map /sdcard/osmdroid/world.map
+  - adb push testzoom4.sqlite /sdcard/osmdroid/testzoom4.sqlite
+  - adb push testzoom4.zip /sdcard/osmdroid/testzoom4.zip
+  - adb push testzoom4.gemf /sdcard/osmdroid/testzoom4.gemf
   #maybe one day it will be added to the repo- adb push ERDC_Whitehorse_GeoPackage.gpkg /sdcard/osmdroid/ERDC_Whitehorse_GeoPackage.gpkg
   #- adb push resources/usgsbase.gemf /sdcard/osmdroid/usgsbase.gemf
   #- adb push resources/usgstopo.sqlite /sdcard/osmdroid/usgstopo.sqlite

OpenStreetMapViewer/src/main/java/org/osmdroid/samplefragments/tileproviders/OfflinePickerSample.java

@@ -91,6 +91,13 @@ public class OfflinePickerSample extends BaseSampleFragment implements View.OnCl
         this.mMapView.setUseDataConnection(true);
     }
 
+    @Override
+    public void onDestroy(){
+        super.onDestroy();
+        if (tileWriter!=null)
+            tileWriter.onDetach();
+    }
+
     /**
      * step 1, users selects files
      */
@@ -128,7 +135,7 @@ public class OfflinePickerSample extends BaseSampleFragment implements View.OnCl
         dialog.show();
     }
 
-
+    IFilesystemCache tileWriter=null;
     /**
      * step two, configure our offline tile provider
      * @param files
@@ -137,8 +144,9 @@ public class OfflinePickerSample extends BaseSampleFragment implements View.OnCl
         if (files == null || files.length == 0)
             return;
         SimpleRegisterReceiver simpleRegisterReceiver = new SimpleRegisterReceiver(getContext());
+        if (tileWriter!=null)
+            tileWriter.onDetach();
 
-        IFilesystemCache tileWriter;
 
         if (Build.VERSION.SDK_INT < 10) {
             tileWriter = new TileWriter();

osmdroid-android/src/main/java/org/osmdroid/tileprovider/modules/MapTileFileArchiveProvider.java

@@ -140,13 +140,17 @@ public class MapTileFileArchiveProvider extends MapTileFileStorageProviderBase {
 
 	@Override
 	public void detach() {
+		clearArcives();
+		super.detach();
+	}
+
+	private void clearArcives(){
 		while(!mArchiveFiles.isEmpty()) {
 			IArchiveFile t = mArchiveFiles.get(0);
 			if (t!=null)
-				mArchiveFiles.get(0).close();
+				t.close();
 			mArchiveFiles.remove(0);
 		}
-		super.detach();
 	}
 
 	// ===========================================================
@@ -154,8 +158,7 @@ public class MapTileFileArchiveProvider extends MapTileFileStorageProviderBase {
 	// ===========================================================
 
 	private void findArchiveFiles() {
-
-		mArchiveFiles.clear();
+		clearArcives();
 
 		if (!isSdCardAvailable()) {
 			return;
@@ -200,6 +203,7 @@ public class MapTileFileArchiveProvider extends MapTileFileStorageProviderBase {
 		@Override
 		public Drawable loadTile(final MapTile pTile) {
 
+			Drawable returnValue=null;
 			ITileSource tileSource = mTileSource.get();
 			if (tileSource == null) {
 				return null;
@@ -225,7 +229,7 @@ public class MapTileFileArchiveProvider extends MapTileFileStorageProviderBase {
 						Log.d(IMapView.LOGTAG,"Use tile from archive: " + pTile);
 					}
 					final Drawable drawable = tileSource.getDrawable(inputStream);
-					return drawable;
+					returnValue = drawable;
 				}
 			} catch (final Throwable e) {
 				Log.e(IMapView.LOGTAG,"Error loading tile", e);
@@ -235,7 +239,7 @@ public class MapTileFileArchiveProvider extends MapTileFileStorageProviderBase {
 				}
 			}
 
-			return null;
+			return returnValue;
 		}
 	}
 }

osmdroid-android/src/main/java/org/osmdroid/util/GEMFFile.java

@@ -20,6 +20,9 @@ import java.util.TreeSet;
  *
  * Reference: https://sites.google.com/site/abudden/android-map-store
  *
+ * Do not reference any android specific code in this class, it is reused in the JRE
+ * Tile Packager
+ *
  * @author A. S. Budden
  * @author Erik Burrows
  *
@@ -575,7 +578,9 @@ public class GEMFFile {
 
 		long dataOffset;
 		int dataLength;
-
+		InputStream returnValue=null;
+		GEMFInputStream stream=null;
+		ByteArrayOutputStream byteBuffer=null;
 		try	{
 
 			// Determine offset to requested tile record in the header
@@ -612,11 +617,9 @@ public class GEMFFile {
 			// Read data block into a byte array
 			pDataFile.seek(dataOffset);
 
-
-
-			GEMFInputStream stream= new GEMFInputStream(mFileNames.get(index), dataOffset, dataLength);
+			stream= new GEMFInputStream(mFileNames.get(index), dataOffset, dataLength);
 			// this dynamically extends to take the bytes you read
-			ByteArrayOutputStream byteBuffer = new ByteArrayOutputStream();
+			byteBuffer = new ByteArrayOutputStream();
 
 			// this is storage overwritten on each iteration with bytes
 			int bufferSize = 1024;
@@ -633,11 +636,26 @@ public class GEMFFile {
 
 			// and then we can return your byte array.
 			byte[] bits = byteBuffer.toByteArray();
-			return new ByteArrayInputStream(bits);
+			returnValue= new ByteArrayInputStream(bits);
 
 		} catch (final java.io.IOException e) {
-			return null;
+			e.printStackTrace();
+		} finally {
+			if (byteBuffer!=null)
+				try {
+					byteBuffer.close();
+				} catch (IOException e) {
+					e.printStackTrace();
 				}
+			if (stream!=null)
+				try {
+					stream.close();
+				} catch (IOException e) {
+					e.printStackTrace();
+				}
+
+		}
+		return returnValue;
 	}