Merge branch 'develop' into glide-48

51 files changed, 108 insertions, 122 deletions

diff --git a/core/src/main/java/de/danoeh/antennapod/core/UpdateManager.java b/core/src/main/java/de/danoeh/antennapod/core/UpdateManager.java
index ea07fc76e..8ad70c328 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/UpdateManager.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/UpdateManager.java
@@ -10,20 +10,15 @@ import android.util.Log;
 
 import org.antennapod.audio.MediaPlayer;
 
-import java.io.File;
-import java.util.List;
-
-import de.danoeh.antennapod.core.feed.Feed;
-import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
-import de.danoeh.antennapod.core.storage.DBReader;
-import de.danoeh.antennapod.core.storage.DBWriter;
 
 /*
  * This class's job is do perform maintenance tasks whenever the app has been updated
  */
 class UpdateManager {
 
+    private UpdateManager(){}
+
     private static final String TAG = UpdateManager.class.getSimpleName();
 
     private static final String PREF_NAME = "app_version";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/asynctask/FeedRemover.java b/core/src/main/java/de/danoeh/antennapod/core/asynctask/FeedRemover.java
index 74693cf21..4504b2e7f 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/asynctask/FeedRemover.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/asynctask/FeedRemover.java
@@ -2,14 +2,12 @@ package de.danoeh.antennapod.core.asynctask;
 
 import android.app.ProgressDialog;
 import android.content.Context;
-import android.content.Intent;
 import android.os.AsyncTask;
 
 import java.util.concurrent.ExecutionException;
 
 import de.danoeh.antennapod.core.R;
 import de.danoeh.antennapod.core.feed.Feed;
-import de.danoeh.antennapod.core.service.download.DownloadService;
 import de.danoeh.antennapod.core.service.playback.PlaybackService;
 import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.util.IntentUtils;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrClickWorker.java b/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrClickWorker.java
index f4c99011a..318e404c8 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrClickWorker.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrClickWorker.java
@@ -10,7 +10,6 @@ import android.support.v4.app.NotificationCompat;
 import android.util.Log;
 import android.widget.Toast;
 
-import de.danoeh.antennapod.core.util.gui.NotificationUtils;
 import org.shredzone.flattr4j.exception.FlattrException;
 
 import java.util.LinkedList;
@@ -27,6 +26,7 @@ import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.util.NetworkUtils;
 import de.danoeh.antennapod.core.util.flattr.FlattrThing;
 import de.danoeh.antennapod.core.util.flattr.FlattrUtils;
+import de.danoeh.antennapod.core.util.gui.NotificationUtils;
 
 /**
  * Performs a click action in a background thread.
diff --git a/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrStatusFetcher.java b/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrStatusFetcher.java
index 420a60469..6d9ab2bd3 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrStatusFetcher.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/asynctask/FlattrStatusFetcher.java
@@ -19,11 +19,9 @@ import de.danoeh.antennapod.core.util.flattr.FlattrUtils;
 
 public class FlattrStatusFetcher extends Thread {
     private static final String TAG = "FlattrStatusFetcher";
-    private final Context context;
 
     public FlattrStatusFetcher(Context context) {
         super();
-        this.context = context;
     }
 
     @Override
diff --git a/core/src/main/java/de/danoeh/antennapod/core/feed/FeedComponent.java b/core/src/main/java/de/danoeh/antennapod/core/feed/FeedComponent.java
index a3f91b1c9..2610d253f 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/feed/FeedComponent.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/feed/FeedComponent.java
@@ -50,7 +50,7 @@ public abstract class FeedComponent {
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
+        if (o == null || !(o instanceof FeedComponent)) return false;
 
         FeedComponent that = (FeedComponent) o;
 
@@ -62,4 +62,4 @@ public abstract class FeedComponent {
     public int hashCode() {
         return (int) (id ^ (id >>> 32));
     }
-}
\ No newline at end of file
+}
diff --git a/core/src/main/java/de/danoeh/antennapod/core/feed/FeedItem.java b/core/src/main/java/de/danoeh/antennapod/core/feed/FeedItem.java
index b0a87c885..0f0343f25 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/feed/FeedItem.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/feed/FeedItem.java
@@ -2,9 +2,8 @@ package de.danoeh.antennapod.core.feed;
 
 import android.database.Cursor;
 import android.support.annotation.Nullable;
-
 import android.text.TextUtils;
-import de.danoeh.antennapod.core.asynctask.ImageResource;
+
 import org.apache.commons.lang3.builder.ToStringBuilder;
 import org.apache.commons.lang3.builder.ToStringStyle;
 
@@ -15,6 +14,7 @@ import java.util.Set;
 import java.util.concurrent.Callable;
 import java.util.concurrent.TimeUnit;
 
+import de.danoeh.antennapod.core.asynctask.ImageResource;
 import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.PodDBAdapter;
 import de.danoeh.antennapod.core.util.ShownotesProvider;
@@ -194,7 +194,7 @@ public class FeedItem extends FeedComponent implements ShownotesProvider, Flattr
         if (other.link != null) {
             link = other.link;
         }
-        if (other.pubDate != null && other.pubDate != pubDate) {
+        if (other.pubDate != null && other.pubDate.equals(pubDate)) {
             pubDate = other.pubDate;
         }
         if (other.media != null) {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/feed/FeedMedia.java b/core/src/main/java/de/danoeh/antennapod/core/feed/FeedMedia.java
index 73d2bb34d..39994ec16 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/feed/FeedMedia.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/feed/FeedMedia.java
@@ -532,8 +532,8 @@ public class FeedMedia extends FeedFile implements Playable {
                     UserPreferences.isAutoFlattr() &&
                     item.getPaymentLink() != null &&
                     item.getFlattrStatus().getUnflattred() &&
-                    (completed && autoFlattrThreshold <= 1.0f ||
-                            played_duration >= autoFlattrThreshold * duration)) {
+                    ((completed && autoFlattrThreshold <= 1.0f) ||
+                            (played_duration >= autoFlattrThreshold * duration))) {
                 DBTasks.flattrItemIfLoggedIn(context, item);
             }
         }
@@ -626,6 +626,9 @@ public class FeedMedia extends FeedFile implements Playable {
 
     @Override
     public boolean equals(Object o) {
+        if (o == null) {
+            return false;
+        }
         if (FeedMediaFlavorHelper.instanceOfRemoteMedia(o)) {
             return o.equals(this);
         }
diff --git a/core/src/main/java/de/danoeh/antennapod/core/glide/ApGlideSettings.java b/core/src/main/java/de/danoeh/antennapod/core/glide/ApGlideSettings.java
index fc1acd0e1..d0061af99 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/glide/ApGlideSettings.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/glide/ApGlideSettings.java
@@ -6,6 +6,7 @@ import com.bumptech.glide.load.engine.DiskCacheStrategy;
  * The settings that AntennaPod will use for various Glide options
  */
 public class ApGlideSettings {
+    private ApGlideSettings(){}
 
     public static final DiskCacheStrategy AP_DISK_CACHE_STRATEGY = DiskCacheStrategy.ALL;
 }
diff --git a/core/src/main/java/de/danoeh/antennapod/core/gpoddernet/model/GpodnetEpisodeAction.java b/core/src/main/java/de/danoeh/antennapod/core/gpoddernet/model/GpodnetEpisodeAction.java
index b76988fd8..330cde525 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/gpoddernet/model/GpodnetEpisodeAction.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/gpoddernet/model/GpodnetEpisodeAction.java
@@ -169,7 +169,7 @@ public class GpodnetEpisodeAction {
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
+        if (o == null || !(o instanceof GpodnetEpisodeAction)) return false;
 
         GpodnetEpisodeAction that = (GpodnetEpisodeAction) o;
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/preferences/GpodnetPreferences.java b/core/src/main/java/de/danoeh/antennapod/core/preferences/GpodnetPreferences.java
index b51b8d996..5b17dd338 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/preferences/GpodnetPreferences.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/preferences/GpodnetPreferences.java
@@ -24,6 +24,8 @@ import de.danoeh.antennapod.core.service.GpodnetSyncService;
  */
 public class GpodnetPreferences {
 
+    private GpodnetPreferences(){}
+
     private static final String TAG = "GpodnetPreferences";
 
     private static final String PREF_NAME = "gpodder.net";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/preferences/SleepTimerPreferences.java b/core/src/main/java/de/danoeh/antennapod/core/preferences/SleepTimerPreferences.java
index b7ed890f5..0f3a9fcb3 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/preferences/SleepTimerPreferences.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/preferences/SleepTimerPreferences.java
@@ -23,7 +23,6 @@ public class SleepTimerPreferences {
     private static final String DEFAULT_VALUE = "15";
     private static final int DEFAULT_TIME_UNIT = 1;
 
-    private static Context context;
     private static SharedPreferences prefs;
 
     /**
diff --git a/core/src/main/java/de/danoeh/antennapod/core/preferences/UserPreferences.java b/core/src/main/java/de/danoeh/antennapod/core/preferences/UserPreferences.java
index 6aaf65e18..e6b5f9e1b 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/preferences/UserPreferences.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/preferences/UserPreferences.java
@@ -8,14 +8,7 @@ import android.support.annotation.NonNull;
 import android.support.v4.app.NotificationCompat;
 import android.text.TextUtils;
 import android.util.Log;
-import de.danoeh.antennapod.core.R;
-import de.danoeh.antennapod.core.service.download.ProxyConfig;
-import de.danoeh.antennapod.core.storage.APCleanupAlgorithm;
-import de.danoeh.antennapod.core.storage.APNullCleanupAlgorithm;
-import de.danoeh.antennapod.core.storage.APQueueCleanupAlgorithm;
-import de.danoeh.antennapod.core.storage.EpisodeCleanupAlgorithm;
-import de.danoeh.antennapod.core.util.Converter;
-import de.danoeh.antennapod.core.util.download.AutoUpdateManager;
+
 import org.json.JSONArray;
 import org.json.JSONException;
 
@@ -27,6 +20,15 @@ import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.TimeUnit;
 
+import de.danoeh.antennapod.core.R;
+import de.danoeh.antennapod.core.service.download.ProxyConfig;
+import de.danoeh.antennapod.core.storage.APCleanupAlgorithm;
+import de.danoeh.antennapod.core.storage.APNullCleanupAlgorithm;
+import de.danoeh.antennapod.core.storage.APQueueCleanupAlgorithm;
+import de.danoeh.antennapod.core.storage.EpisodeCleanupAlgorithm;
+import de.danoeh.antennapod.core.util.Converter;
+import de.danoeh.antennapod.core.util.download.AutoUpdateManager;
+
 /**
  * Provides access to preferences set by the user in the settings screen. A
  * private instance of this class must first be instantiated via
@@ -34,6 +36,7 @@ import java.util.concurrent.TimeUnit;
  * when called.
  */
 public class UserPreferences {
+    private UserPreferences(){}
 
     private static final String IMPORT_DIR = "import/";
 
@@ -44,7 +47,7 @@ public class UserPreferences {
     public static final String PREF_HIDDEN_DRAWER_ITEMS = "prefHiddenDrawerItems";
     private static final String PREF_DRAWER_FEED_ORDER = "prefDrawerFeedOrder";
     private static final String PREF_DRAWER_FEED_COUNTER = "prefDrawerFeedIndicator";
-    private static final String PREF_EXPANDED_NOTIFICATION = "prefExpandNotify";
+    public static final String PREF_EXPANDED_NOTIFICATION = "prefExpandNotify";
     private static final String PREF_PERSISTENT_NOTIFICATION = "prefPersistNotify";
     public static final String PREF_COMPACT_NOTIFICATION_BUTTONS = "prefCompactNotificationButtons";
     public static final String PREF_LOCKSCREEN_BACKGROUND = "prefLockscreenBackground";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/receiver/PlayerWidget.java b/core/src/main/java/de/danoeh/antennapod/core/receiver/PlayerWidget.java
index edc2ea3e0..7663cdbe4 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/receiver/PlayerWidget.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/receiver/PlayerWidget.java
@@ -6,10 +6,11 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.util.Log;
-import de.danoeh.antennapod.core.service.PlayerWidgetJobService;
 
 import java.util.Arrays;
 
+import de.danoeh.antennapod.core.service.PlayerWidgetJobService;
+
 
 public class PlayerWidget extends AppWidgetProvider {
     private static final String TAG = "PlayerWidget";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/FeedUpdateJobService.java b/core/src/main/java/de/danoeh/antennapod/core/service/FeedUpdateJobService.java
index 55a8d6b86..7d80d4e7c 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/FeedUpdateJobService.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/FeedUpdateJobService.java
@@ -5,6 +5,7 @@ import android.app.job.JobService;
 import android.os.Build;
 import android.support.annotation.RequiresApi;
 import android.util.Log;
+
 import de.danoeh.antennapod.core.ClientConfig;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.util.FeedUpdateUtils;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/GpodnetSyncService.java b/core/src/main/java/de/danoeh/antennapod/core/service/GpodnetSyncService.java
index fe6e8c400..5584991ca 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/GpodnetSyncService.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/GpodnetSyncService.java
@@ -6,8 +6,8 @@ import android.app.PendingIntent;
 import android.content.Context;
 import android.content.Intent;
 import android.support.annotation.NonNull;
-import android.support.v4.app.JobIntentService;
 import android.support.v4.app.NotificationCompat;
+import android.support.v4.app.SafeJobIntentService;
 import android.support.v4.util.ArrayMap;
 import android.util.Log;
 import android.util.Pair;
@@ -44,7 +44,7 @@ import de.danoeh.antennapod.core.util.gui.NotificationUtils;
  * Synchronizes local subscriptions with gpodder.net service. The service should be started with ACTION_SYNC as an action argument.
  * This class also provides static methods for starting the GpodnetSyncService.
  */
-public class GpodnetSyncService extends JobIntentService {
+public class GpodnetSyncService extends SafeJobIntentService {
 
     private static final String TAG = "GpodnetSyncService";
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/PlayerWidgetJobService.java b/core/src/main/java/de/danoeh/antennapod/core/service/PlayerWidgetJobService.java
index d2214cac8..6dab9a561 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/PlayerWidgetJobService.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/PlayerWidgetJobService.java
@@ -9,23 +9,24 @@ import android.content.ServiceConnection;
 import android.os.Build;
 import android.os.IBinder;
 import android.support.annotation.NonNull;
-import android.support.v4.app.JobIntentService;
+import android.support.v4.app.SafeJobIntentService;
 import android.util.Log;
 import android.view.KeyEvent;
 import android.view.View;
 import android.widget.RemoteViews;
+
 import de.danoeh.antennapod.core.R;
 import de.danoeh.antennapod.core.receiver.MediaButtonReceiver;
+import de.danoeh.antennapod.core.receiver.PlayerWidget;
 import de.danoeh.antennapod.core.service.playback.PlaybackService;
 import de.danoeh.antennapod.core.service.playback.PlayerStatus;
 import de.danoeh.antennapod.core.util.Converter;
 import de.danoeh.antennapod.core.util.playback.Playable;
-import de.danoeh.antennapod.core.receiver.PlayerWidget;
 
 /**
  * Updates the state of the player widget
  */
-public class PlayerWidgetJobService extends JobIntentService {
+public class PlayerWidgetJobService extends SafeJobIntentService {
 
     private static final String TAG = "PlayerWidgetJobService";
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/download/AntennapodHttpClient.java b/core/src/main/java/de/danoeh/antennapod/core/service/download/AntennapodHttpClient.java
index 57d099dfc..97007a214 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/download/AntennapodHttpClient.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/download/AntennapodHttpClient.java
@@ -40,6 +40,9 @@ import okhttp3.internal.http.StatusLine;
  * Provides access to a HttpClient singleton.
  */
 public class AntennapodHttpClient {
+
+    private AntennapodHttpClient(){}
+
     private static final String TAG = "AntennapodHttpClient";
 
     private static final int CONNECTION_TIMEOUT = 30000;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java b/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java
index 75c28564e..48234c387 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadRequest.java
@@ -124,7 +124,7 @@ public class DownloadRequest implements Parcelable {
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
-        if (o == null || getClass() != o.getClass()) return false;
+        if (o == null || !(o instanceof DownloadRequest)) return false;
 
         DownloadRequest that = (DownloadRequest) o;
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadService.java b/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadService.java
index 4bd2d8f19..ffbe7e7d1 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadService.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/download/DownloadService.java
@@ -14,14 +14,13 @@ import android.os.Handler;
 import android.os.IBinder;
 import android.support.annotation.NonNull;
 import android.support.annotation.VisibleForTesting;
+import android.support.annotation.Nullable;
 import android.support.v4.app.NotificationCompat;
 import android.text.TextUtils;
 import android.util.Log;
 import android.util.Pair;
 import android.webkit.URLUtil;
 
-import de.danoeh.antennapod.core.storage.PodDBAdapter;
-import de.danoeh.antennapod.core.util.gui.NotificationUtils;
 import org.apache.commons.io.FileUtils;
 import org.xml.sax.SAXException;
 
@@ -31,10 +30,8 @@ import java.net.HttpURLConnection;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Date;
-import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
-import java.util.Set;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.Callable;
 import java.util.concurrent.CompletionService;
@@ -69,12 +66,14 @@ import de.danoeh.antennapod.core.storage.DBTasks;
 import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.storage.DownloadRequestException;
 import de.danoeh.antennapod.core.storage.DownloadRequester;
+import de.danoeh.antennapod.core.storage.PodDBAdapter;
 import de.danoeh.antennapod.core.syndication.handler.FeedHandler;
 import de.danoeh.antennapod.core.syndication.handler.FeedHandlerResult;
 import de.danoeh.antennapod.core.syndication.handler.UnsupportedFeedtypeException;
 import de.danoeh.antennapod.core.util.ChapterUtils;
 import de.danoeh.antennapod.core.util.DownloadError;
 import de.danoeh.antennapod.core.util.InvalidFeedException;
+import de.danoeh.antennapod.core.util.gui.NotificationUtils;
 import de.greenrobot.event.EventBus;
 
 /**
@@ -117,11 +116,6 @@ public class DownloadService extends Service {
     private CompletionService<Downloader> downloadExecutor;
     private FeedSyncThread feedSyncThread;
 
-    /**
-     * Number of threads of downloadExecutor.
-     */
-    private static final int NUM_PARALLEL_DOWNLOADS = 6;
-
     private DownloadRequester requester;
 
 
@@ -862,22 +856,6 @@ public class DownloadService extends Service {
             return true;
         }
 
-        /**
-         * Delete files that aren't needed anymore
-         */
-        private void cleanup(Feed feed) {
-            if (feed.getFile_url() != null) {
-                if (new File(feed.getFile_url()).delete()) {
-                    Log.d(TAG, "Successfully deleted cache file.");
-                } else {
-                    Log.e(TAG, "Failed to delete cache file.");
-                }
-                feed.setFile_url(null);
-            } else {
-                Log.d(TAG, "Didn't delete cache file: File url is not set.");
-            }
-        }
-
         public void shutdown() {
             isActive = false;
             if (isCollectingRequests) {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java b/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java
index 8cce02155..842ad0c60 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/download/HttpDownloader.java
@@ -304,7 +304,7 @@ public class HttpDownloader extends Downloader {
             String encoded = ByteString.of(bytes).base64();
             return "Basic " + encoded;
         } catch (UnsupportedEncodingException e) {
-            throw new AssertionError();
+            throw new AssertionError(e);
         }
     }
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/playback/ExoPlayerWrapper.java b/core/src/main/java/de/danoeh/antennapod/core/service/playback/ExoPlayerWrapper.java
index cc9d2ce2d..e1d87e1d5 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/playback/ExoPlayerWrapper.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/playback/ExoPlayerWrapper.java
@@ -3,6 +3,7 @@ package de.danoeh.antennapod.core.service.playback;
 import android.content.Context;
 import android.net.Uri;
 import android.view.SurfaceHolder;
+
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.DefaultLoadControl;
 import com.google.android.exoplayer2.DefaultRenderersFactory;
@@ -22,9 +23,11 @@ import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
 import com.google.android.exoplayer2.util.Util;
-import de.danoeh.antennapod.core.util.playback.IPlayer;
+
 import org.antennapod.audio.MediaPlayer;
 
+import de.danoeh.antennapod.core.util.playback.IPlayer;
+
 
 public class ExoPlayerWrapper implements IPlayer {
     private final Context mContext;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlaybackService.java b/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlaybackService.java
index 0b4caf0c8..f2be7fbb1 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlaybackService.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlaybackService.java
@@ -24,13 +24,13 @@ import android.os.Vibrator;
 import android.preference.PreferenceManager;
 import android.support.annotation.NonNull;
 import android.support.annotation.StringRes;
+import android.support.v4.app.NotificationCompat;
 import android.support.v4.media.MediaBrowserCompat;
 import android.support.v4.media.MediaBrowserServiceCompat;
 import android.support.v4.media.MediaDescriptionCompat;
 import android.support.v4.media.MediaMetadataCompat;
 import android.support.v4.media.session.MediaSessionCompat;
 import android.support.v4.media.session.PlaybackStateCompat;
-import android.support.v4.app.NotificationCompat;
 import android.text.TextUtils;
 import android.util.Log;
 import android.util.Pair;
@@ -67,8 +67,8 @@ import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.storage.FeedSearcher;
 import de.danoeh.antennapod.core.util.IntList;
 import de.danoeh.antennapod.core.util.IntentUtils;
-import de.danoeh.antennapod.core.util.gui.NotificationUtils;
 import de.danoeh.antennapod.core.util.QueueAccess;
+import de.danoeh.antennapod.core.util.gui.NotificationUtils;
 import de.danoeh.antennapod.core.util.playback.ExternalMedia;
 import de.danoeh.antennapod.core.util.playback.Playable;
 import de.greenrobot.event.EventBus;
@@ -603,14 +603,6 @@ public class PlaybackService extends MediaBrowserServiceCompat {
         mediaPlayer.setVideoSurface(sh);
     }
 
-    /**
-     * Called when the surface holder of the mediaplayer has to be changed.
-     */
-    private void resetVideoSurface() {
-        taskManager.cancelPositionSaver();
-        mediaPlayer.resetVideoSurface();
-    }
-
     public void notifyVideoSurfaceAbandoned() {
         mediaPlayer.pause(true, false);
         mediaPlayer.resetVideoSurface();
@@ -1808,7 +1800,7 @@ public class PlaybackService extends MediaBrowserServiceCompat {
         public boolean onMediaButtonEvent(final Intent mediaButton) {
             Log.d(TAG, "onMediaButtonEvent(" + mediaButton + ")");
             if (mediaButton != null) {
-                KeyEvent keyEvent = (KeyEvent) mediaButton.getParcelableExtra(Intent.EXTRA_KEY_EVENT);
+                KeyEvent keyEvent = mediaButton.getParcelableExtra(Intent.EXTRA_KEY_EVENT);
                 if (keyEvent != null &&
                         keyEvent.getAction() == KeyEvent.ACTION_DOWN &&
                         keyEvent.getRepeatCount() == 0) {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlayerStatus.java b/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlayerStatus.java
index 8a222d7ec..4f2ae34f8 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlayerStatus.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/service/playback/PlayerStatus.java
@@ -12,7 +12,7 @@ public enum PlayerStatus {
 	INITIALIZING(9),			// playback service is loading the Playable's metadata
 	INITIALIZED(10);	// playback service was started, data source of media player was set.
 
-	private int statusValue;
+	private final int statusValue;
     private static final PlayerStatus[] fromOrdinalLookup;
 
     static {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/DBReader.java b/core/src/main/java/de/danoeh/antennapod/core/storage/DBReader.java
index 456d05ded..718459db8 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/DBReader.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/DBReader.java
@@ -75,7 +75,7 @@ public final class DBReader {
             cursor = adapter.getAllFeedsCursor();
             List<Feed> feeds = new ArrayList<>(cursor.getCount());
             while (cursor.moveToNext()) {
-                Feed feed = extractFeedFromCursorRow(adapter, cursor);
+                Feed feed = extractFeedFromCursorRow(cursor);
                 feeds.add(feed);
             }
             return feeds;
@@ -243,7 +243,7 @@ public final class DBReader {
         return result;
     }
 
-    private static Feed extractFeedFromCursorRow(PodDBAdapter adapter, Cursor cursor) {
+    private static Feed extractFeedFromCursorRow(Cursor cursor) {
         Feed feed = Feed.fromCursor(cursor);
         FeedPreferences preferences = FeedPreferences.fromCursor(cursor);
         feed.setPreferences(preferences);
@@ -580,7 +580,7 @@ public final class DBReader {
         try {
             cursor = adapter.getFeedCursor(feedId);
             if (cursor.moveToNext()) {
-                feed = extractFeedFromCursorRow(adapter, cursor);
+                feed = extractFeedFromCursorRow(cursor);
                 feed.setItems(getFeedItemList(feed));
             } else {
                 Log.e(TAG, "getFeed could not find feed with id " + feedId);
@@ -1007,7 +1007,7 @@ public final class DBReader {
         Cursor feedCursor = adapter.getFeedsInFlattrQueueCursor();
         if (feedCursor.moveToFirst()) {
             do {
-                result.add(extractFeedFromCursorRow(adapter, feedCursor));
+                result.add(extractFeedFromCursorRow(feedCursor));
             } while (feedCursor.moveToNext());
         }
         feedCursor.close();
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java b/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java
index 8eed10cd7..ba7d4b47b 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/DBTasks.java
@@ -1,11 +1,9 @@
 package de.danoeh.antennapod.core.storage;
 
 import android.content.Context;
-import android.content.Intent;
 import android.content.SharedPreferences;
 import android.database.Cursor;
 import android.support.annotation.Nullable;
-import android.support.v4.content.ContextCompat;
 import android.util.Log;
 
 import java.util.ArrayList;
@@ -777,10 +775,8 @@ public final class DBTasks {
      */
     abstract static class QueryTask<T> implements Callable<T> {
         private T result;
-        private final Context context;
 
         public QueryTask(Context context) {
-            this.context = context;
         }
 
         @Override
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/DBUpgrader.java b/core/src/main/java/de/danoeh/antennapod/core/storage/DBUpgrader.java
index 29ed5f7f9..0beb765e7 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/DBUpgrader.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/DBUpgrader.java
@@ -5,6 +5,7 @@ import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
 import android.media.MediaMetadataRetriever;
 import android.util.Log;
+
 import de.danoeh.antennapod.core.feed.FeedItem;
 
 class DBUpgrader {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/DBWriter.java b/core/src/main/java/de/danoeh/antennapod/core/storage/DBWriter.java
index 8bb5bc31a..bbe6145ea 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/DBWriter.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/DBWriter.java
@@ -7,7 +7,6 @@ import android.content.SharedPreferences;
 import android.preference.PreferenceManager;
 import android.util.Log;
 
-import de.danoeh.antennapod.core.util.IntentUtils;
 import org.shredzone.flattr4j.model.Flattr;
 
 import java.io.File;
@@ -42,6 +41,7 @@ import de.danoeh.antennapod.core.preferences.PlaybackPreferences;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.service.download.DownloadStatus;
 import de.danoeh.antennapod.core.service.playback.PlaybackService;
+import de.danoeh.antennapod.core.util.IntentUtils;
 import de.danoeh.antennapod.core.util.LongList;
 import de.danoeh.antennapod.core.util.Permutor;
 import de.danoeh.antennapod.core.util.flattr.FlattrStatus;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java b/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java
index 827874f54..892a4675a 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/DownloadRequester.java
@@ -9,8 +9,6 @@ import android.text.TextUtils;
 import android.util.Log;
 import android.webkit.URLUtil;
 
-import de.danoeh.antennapod.core.service.playback.PlaybackService;
-import de.danoeh.antennapod.core.util.IntentUtils;
 import org.apache.commons.io.FilenameUtils;
 
 import java.io.File;
@@ -25,6 +23,7 @@ import de.danoeh.antennapod.core.preferences.UserPreferences;
 import de.danoeh.antennapod.core.service.download.DownloadRequest;
 import de.danoeh.antennapod.core.service.download.DownloadService;
 import de.danoeh.antennapod.core.util.FileNameGenerator;
+import de.danoeh.antennapod.core.util.IntentUtils;
 import de.danoeh.antennapod.core.util.URLChecker;
 
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/FeedSearcher.java b/core/src/main/java/de/danoeh/antennapod/core/storage/FeedSearcher.java
index aa5706ad0..f91e2ad08 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/FeedSearcher.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/FeedSearcher.java
@@ -19,6 +19,8 @@ import de.danoeh.antennapod.core.util.comparator.SearchResultValueComparator;
  * Performs search on Feeds and FeedItems
  */
 public class FeedSearcher {
+    private FeedSearcher(){}
+
     private static final String TAG = "FeedSearcher";
 
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/storage/PodDBAdapter.java b/core/src/main/java/de/danoeh/antennapod/core/storage/PodDBAdapter.java
index 51b41d3b3..8ebd8eeb5 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/storage/PodDBAdapter.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/storage/PodDBAdapter.java
@@ -12,8 +12,20 @@ import android.database.sqlite.SQLiteDatabase;
 import android.database.sqlite.SQLiteDatabase.CursorFactory;
 import android.database.sqlite.SQLiteOpenHelper;
 import android.media.MediaMetadataRetriever;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
 import android.text.TextUtils;
 import android.util.Log;
+
+import org.apache.commons.io.FileUtils;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+
 import de.danoeh.antennapod.core.R;
 import de.danoeh.antennapod.core.event.ProgressEvent;
 import de.danoeh.antennapod.core.feed.Chapter;
@@ -26,14 +38,6 @@ import de.danoeh.antennapod.core.service.download.DownloadStatus;
 import de.danoeh.antennapod.core.util.LongIntMap;
 import de.danoeh.antennapod.core.util.flattr.FlattrStatus;
 import de.greenrobot.event.EventBus;
-import org.apache.commons.io.FileUtils;
-
-import java.io.File;
-import java.io.IOException;
-import java.util.Arrays;
-import java.util.Collections;
-import java.util.List;
-import java.util.Set;
 
 // TODO Remove media column from feeditem table
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/NSRSS20.java b/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/NSRSS20.java
index a1100a976..e391af1b2 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/NSRSS20.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/NSRSS20.java
@@ -5,7 +5,6 @@ import android.util.Log;
 
 import org.xml.sax.Attributes;
 
-import de.danoeh.antennapod.core.feed.Feed;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
 import de.danoeh.antennapod.core.syndication.handler.HandlerState;
@@ -22,9 +21,6 @@ public class NSRSS20 extends Namespace {
 
     private static final String TAG = "NSRSS20";
 
-    private static final String NSTAG = "rss";
-	private static final String NSURI = "";
-
     public static final String CHANNEL = "channel";
 	public static final String ITEM = "item";
     private static final String GUID = "guid";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/Namespace.java b/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/Namespace.java
index 1836bbec1..e5fbdb9bb 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/Namespace.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/Namespace.java
@@ -15,7 +15,6 @@ public abstract class Namespace {
 	public abstract SyndElement handleElementStart(String localName, HandlerState state, Attributes attributes);
 	
 	/** Called by a Feedhandler when in endElement and it detects a namespace element 
-	 * 	@return true if namespace handled the element, false if it ignored it
 	 * */
 	public abstract void handleElementEnd(String localName, HandlerState state);
 	
diff --git a/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/atom/NSAtom.java b/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/atom/NSAtom.java
index aab1b1a5b..83957456a 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/atom/NSAtom.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/syndication/namespace/atom/NSAtom.java
@@ -47,8 +47,6 @@ public class NSAtom extends Namespace {
     private static final String LINK_REL_ARCHIVES = "archives";
     private static final String LINK_REL_ENCLOSURE = "enclosure";
     private static final String LINK_REL_PAYMENT = "payment";
-    private static final String LINK_REL_RELATED = "related";
-    private static final String LINK_REL_SELF = "self";
     private static final String LINK_REL_NEXT = "next";
     // type-values
     private static final String LINK_TYPE_ATOM = "application/atom+xml";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/Converter.java b/core/src/main/java/de/danoeh/antennapod/core/util/Converter.java
index b513fbe99..3cb226add 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/Converter.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/Converter.java
@@ -28,7 +28,6 @@ public final class Converter {
     /** Determines the length of the number for best readability.*/
     private static final int NUM_LENGTH = 1024;
     
-    private static final int DAYS_MIL = 86400000;
     private static final int HOURS_MIL = 3600000;
 	private static final int MINUTES_MIL = 60000;
 	private static final int SECONDS_MIL = 1000;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/DateUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/DateUtils.java
index e17d8de3e..5141e3a78 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/DateUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/DateUtils.java
@@ -17,7 +17,9 @@ import java.util.TimeZone;
  */
 public class DateUtils {
 
-    private static final String TAG = "DateUtils";
+    private DateUtils(){}
+
+	private static final String TAG = "DateUtils";
 
     private static final TimeZone defaultTimezone = TimeZone.getTimeZone("GMT");
 
@@ -135,7 +137,7 @@ public class DateUtils {
         if (parts.length >= 2) {
             result += Integer.parseInt(parts[idx]) * 60000L;
             idx++;
-            result += (Float.parseFloat(parts[idx])) * 1000L;
+            result += (long) (Float.parseFloat(parts[idx]) * 1000L);
         }
         return result;
     }
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/FeedItemUtil.java b/core/src/main/java/de/danoeh/antennapod/core/util/FeedItemUtil.java
index 76a6549ae..826c06822 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/FeedItemUtil.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/FeedItemUtil.java
@@ -5,6 +5,7 @@ import java.util.List;
 import de.danoeh.antennapod.core.feed.FeedItem;
 
 public class FeedItemUtil {
+    private FeedItemUtil(){}
 
     public static int indexOfItemWithDownloadUrl(List<FeedItem> items, String downloadUrl) {
         if(items == null) {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/IntentUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/IntentUtils.java
index aaaaf8f4d..e81ab47ed 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/IntentUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/IntentUtils.java
@@ -8,6 +8,7 @@ import android.content.pm.ResolveInfo;
 import java.util.List;
 
 public class IntentUtils {
+    private IntentUtils(){}
 
     /*
      *  Checks if there is at least one exported activity that can be performed for the intent
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/LangUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/LangUtils.java
index 7ec7f84c4..90e0b0981 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/LangUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/LangUtils.java
@@ -5,6 +5,9 @@ import android.support.v4.util.ArrayMap;
 import java.nio.charset.Charset;
 
 public class LangUtils {
+
+	private LangUtils(){}
+
 	public static final Charset UTF_8 = Charset.forName("UTF-8");
 
 	private static final ArrayMap<String, String> languages;
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/NetworkUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/NetworkUtils.java
index cbda583fa..0120790ed 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/NetworkUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/NetworkUtils.java
@@ -22,11 +22,11 @@ import okhttp3.OkHttpClient;
 import okhttp3.Request;
 import okhttp3.Response;
 import rx.Observable;
-import rx.Subscriber;
 import rx.android.schedulers.AndroidSchedulers;
 import rx.schedulers.Schedulers;
 
 public class NetworkUtils {
+    private NetworkUtils(){}
 
 	private static final String TAG = NetworkUtils.class.getSimpleName();
 
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/RewindAfterPauseUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/RewindAfterPauseUtils.java
index ee306a401..d1818aeef 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/RewindAfterPauseUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/RewindAfterPauseUtils.java
@@ -9,6 +9,7 @@ import java.util.concurrent.TimeUnit;
  * Media file should be "rewinded" x seconds after user resumes the playback.
  */
 public class RewindAfterPauseUtils {
+    private RewindAfterPauseUtils(){}
 
     public static final long ELAPSED_TIME_FOR_SHORT_REWIND = TimeUnit.MINUTES.toMillis(1);
     public static final long ELAPSED_TIME_FOR_MEDIUM_REWIND = TimeUnit.HOURS.toMillis(1);
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/StorageUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/StorageUtils.java
index 1ef81bf64..3a6bf5755 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/StorageUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/StorageUtils.java
@@ -14,6 +14,8 @@ import de.danoeh.antennapod.core.preferences.UserPreferences;
  * Utility functions for handling storage errors
  */
 public class StorageUtils {
+    private StorageUtils(){}
+
     private static final String TAG = "StorageUtils";
 
     public static boolean storageAvailable() {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/ThemeUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/ThemeUtils.java
index 03d0f10ff..14f091249 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/ThemeUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/ThemeUtils.java
@@ -3,14 +3,15 @@ package de.danoeh.antennapod.core.util;
 import android.content.Context;
 import android.support.annotation.AttrRes;
 import android.support.annotation.ColorInt;
-import android.support.annotation.ColorRes;
 import android.util.Log;
-
 import android.util.TypedValue;
+
 import de.danoeh.antennapod.core.R;
 import de.danoeh.antennapod.core.preferences.UserPreferences;
 
 public class ThemeUtils {
+    private ThemeUtils(){}
+
     private static final String TAG = "ThemeUtils";
 
     public static int getSelectionBackgroundColor() {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/download/AutoUpdateManager.java b/core/src/main/java/de/danoeh/antennapod/core/util/download/AutoUpdateManager.java
index ad723c685..3a2a4ac80 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/download/AutoUpdateManager.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/download/AutoUpdateManager.java
@@ -11,12 +11,13 @@ import android.os.Build;
 import android.os.SystemClock;
 import android.support.annotation.RequiresApi;
 import android.util.Log;
-import de.danoeh.antennapod.core.receiver.FeedUpdateReceiver;
-import de.danoeh.antennapod.core.service.FeedUpdateJobService;
 
 import java.util.Calendar;
 import java.util.concurrent.TimeUnit;
 
+import de.danoeh.antennapod.core.receiver.FeedUpdateReceiver;
+import de.danoeh.antennapod.core.service.FeedUpdateJobService;
+
 public class AutoUpdateManager {
     private static final int JOB_ID_FEED_UPDATE = 42;
     private static final String TAG = "AutoUpdateManager";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrServiceCreator.java b/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrServiceCreator.java
index 45cb56988..d4d5843d2 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrServiceCreator.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrServiceCreator.java
@@ -11,7 +11,9 @@ import de.danoeh.antennapod.core.BuildConfig;
 /** Ensures that only one instance of the FlattrService class exists at a time */
 
 class FlattrServiceCreator {
-	private static final String TAG = "FlattrServiceCreator";
+	private FlattrServiceCreator(){}
+
+	public static final String TAG = "FlattrServiceCreator";
 	
 	private static volatile FlattrService flattrService;
 	
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrUtils.java
index 313d1c2f2..919fc82f2 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/flattr/FlattrUtils.java
@@ -1,8 +1,6 @@
 package de.danoeh.antennapod.core.util.flattr;
 
 import android.content.Context;
-import android.content.DialogInterface;
-import android.content.DialogInterface.OnClickListener;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.net.Uri;
@@ -36,6 +34,8 @@ import de.danoeh.antennapod.core.storage.DBWriter;
  */
 
 public class FlattrUtils {
+    private FlattrUtils(){}
+
     private static final String TAG = "FlattrUtils";
 
     private static final String HOST_NAME = "de.danoeh.antennapod";
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/gui/MoreContentListFooterUtil.java b/core/src/main/java/de/danoeh/antennapod/core/util/gui/MoreContentListFooterUtil.java
index 386f46724..6e5c3e84b 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/gui/MoreContentListFooterUtil.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/gui/MoreContentListFooterUtil.java
@@ -27,8 +27,8 @@ public class MoreContentListFooterUtil {
     }
 
     public void setLoadingState(boolean newState) {
-        final ImageView imageView = (ImageView) root.findViewById(R.id.imgExpand);
-        final ProgressBar progressBar = (ProgressBar) root.findViewById(R.id.progBar);
+        final ImageView imageView = root.findViewById(R.id.imgExpand);
+        final ProgressBar progressBar = root.findViewById(R.id.progBar);
         if (newState) {
             imageView.setVisibility(View.GONE);
             progressBar.setVisibility(View.VISIBLE);
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/gui/NotificationUtils.java b/core/src/main/java/de/danoeh/antennapod/core/util/gui/NotificationUtils.java
index 2a537dc62..52a43aab2 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/gui/NotificationUtils.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/gui/NotificationUtils.java
@@ -6,6 +6,7 @@ import android.app.NotificationManager;
 import android.content.Context;
 import android.os.Build;
 import android.support.annotation.RequiresApi;
+
 import de.danoeh.antennapod.core.R;
 
 public class NotificationUtils {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/playback/MediaPlayerError.java b/core/src/main/java/de/danoeh/antennapod/core/util/playback/MediaPlayerError.java
index a576dd497..b04c02075 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/playback/MediaPlayerError.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/playback/MediaPlayerError.java
@@ -7,6 +7,7 @@ import de.danoeh.antennapod.core.R;
 
 /** Utility class for MediaPlayer errors. */
 public class MediaPlayerError {
+	private MediaPlayerError(){}
 
 	/** Get a human-readable string for a specific error code. */
 	public static String getErrorString(Context context, int code) {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/playback/Playable.java b/core/src/main/java/de/danoeh/antennapod/core/util/playback/Playable.java
index ff7f5b79d..da9b96430 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/playback/Playable.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/playback/Playable.java
@@ -176,6 +176,8 @@ public interface Playable extends Parcelable,
      * Provides utility methods for Playable objects.
      */
     class PlayableUtils {
+        private PlayableUtils(){}
+
         private static final String TAG = "PlayableUtils";
 
         /**
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackController.java b/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackController.java
index 31067839a..408789cc9 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackController.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackController.java
@@ -7,12 +7,10 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.ServiceConnection;
-import android.content.SharedPreferences;
 import android.content.res.TypedArray;
 import android.media.MediaPlayer;
 import android.os.Build;
 import android.os.IBinder;
-import android.preference.PreferenceManager;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 import android.support.v4.content.ContextCompat;
@@ -24,10 +22,8 @@ import android.widget.ImageButton;
 import android.widget.SeekBar;
 import android.widget.TextView;
 
-import java.util.concurrent.RejectedExecutionHandler;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.ScheduledThreadPoolExecutor;
-import java.util.concurrent.ThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 
 import de.danoeh.antennapod.core.R;
@@ -42,12 +38,10 @@ import de.danoeh.antennapod.core.service.playback.PlayerStatus;
 import de.danoeh.antennapod.core.storage.DBTasks;
 import de.danoeh.antennapod.core.util.Converter;
 import de.danoeh.antennapod.core.util.playback.Playable.PlayableUtils;
-import rx.Completable;
 import rx.Observable;
 import rx.Single;
 import rx.Subscription;
 import rx.android.schedulers.AndroidSchedulers;
-import rx.observers.Subscribers;
 import rx.schedulers.Schedulers;
 
 /**
@@ -702,7 +696,7 @@ public abstract class PlaybackController {
         return org.antennapod.audio.MediaPlayer.isPrestoLibraryInstalled(activity.getApplicationContext())
                 || UserPreferences.useSonic()
                 || Build.VERSION.SDK_INT >= 23
-                || playbackService != null && playbackService.canSetSpeed();
+                || (playbackService != null && playbackService.canSetSpeed());
     }
 
     public void setPlaybackSpeed(float speed) {
diff --git a/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackServiceStarter.java b/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackServiceStarter.java
index 3ba553d12..f7d2ee409 100644
--- a/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackServiceStarter.java
+++ b/core/src/main/java/de/danoeh/antennapod/core/util/playback/PlaybackServiceStarter.java
@@ -3,7 +3,9 @@ package de.danoeh.antennapod.core.util.playback;
 import android.content.Context;
 import android.content.Intent;
 import android.media.MediaPlayer;
+import android.support.annotation.NonNull;
 import android.support.v4.content.ContextCompat;
+
 import de.danoeh.antennapod.core.preferences.PlaybackPreferences;
 import de.danoeh.antennapod.core.service.playback.PlaybackService;