Use StringUtils.defaultString().

src/org/kde/kdeconnect/Device.java

@@ -41,6 +41,7 @@ import androidx.core.content.ContextCompat;
 
 import org.apache.commons.collections4.MultiValuedMap;
 import org.apache.commons.collections4.multimap.ArrayListValuedHashMap;
+import org.apache.commons.lang3.StringUtils;
 import org.kde.kdeconnect.Backends.BaseLink;
 import org.kde.kdeconnect.Backends.BasePairingHandler;
 import org.kde.kdeconnect.Helpers.DeviceHelper;
@@ -188,7 +189,7 @@ public class Device implements BaseLink.PacketReceiver {
     }
 
     public String getName() {
-        return name != null ? name : context.getString(R.string.unknown_device);
+        return StringUtils.defaultString(name, context.getString(R.string.unknown_device));
     }
 
     public Drawable getIcon() {

src/org/kde/kdeconnect/Helpers/FilesHelper.java

@@ -32,6 +32,7 @@ import android.util.Log;
 import android.webkit.MimeTypeMap;
 
 import org.apache.commons.io.FilenameUtils;
+import org.apache.commons.lang3.StringUtils;
 import org.kde.kdeconnect.NetworkPacket;
 
 import java.io.File;
@@ -43,8 +44,7 @@ public class FilesHelper {
 
     public static String getMimeTypeFromFile(String file) {
         String mime = MimeTypeMap.getSingleton().getMimeTypeFromExtension(FilenameUtils.getExtension(file));
-        if (mime == null) mime = "*/*";
+        return StringUtils.defaultString(mime, "*/*");
-        return mime;
     }
 
     public static String findNonExistingNameForNewFile(String path, String filename) {

src/org/kde/kdeconnect/Plugins/MprisReceiverPlugin/MprisReceiverPlayer.java

@@ -28,6 +28,8 @@ import android.text.TextUtils;
 
 import androidx.annotation.RequiresApi;
 
+import org.apache.commons.lang3.StringUtils;
+
 @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
 class MprisReceiverPlayer {
 
@@ -102,8 +104,7 @@ class MprisReceiverPlayer {
         MediaMetadata metadata = controller.getMetadata();
         if (metadata == null) return "";
 
-        String album = metadata.getString(MediaMetadata.METADATA_KEY_ALBUM);
+        return StringUtils.defaultString(metadata.getString(MediaMetadata.METADATA_KEY_ALBUM));
-        return album != null ? album : "";
     }
 
     String getArtist() {
@@ -115,7 +116,7 @@ class MprisReceiverPlayer {
         if (TextUtils.isEmpty(artist)) artist = metadata.getString(MediaMetadata.METADATA_KEY_AUTHOR);
         if (TextUtils.isEmpty(artist)) artist = metadata.getString(MediaMetadata.METADATA_KEY_WRITER);
 
-        return artist != null ? artist : "";
+        return StringUtils.defaultString(artist);
     }
 
     String getTitle() {
@@ -124,7 +125,7 @@ class MprisReceiverPlayer {
 
         String title = metadata.getString(MediaMetadata.METADATA_KEY_TITLE);
         if (TextUtils.isEmpty(title)) title = metadata.getString(MediaMetadata.METADATA_KEY_DISPLAY_TITLE);
-        return title != null ? title : "";
+        return StringUtils.defaultString(title);
     }
 
     void previous() {

src/org/kde/kdeconnect/Plugins/NotificationsPlugin/NotificationsPlugin.java

@@ -243,7 +243,7 @@ public class NotificationsPlugin extends Plugin implements NotificationReceiver.
         np.set("id", key);
         np.set("onlyOnce", (notification.flags & NotificationCompat.FLAG_ONLY_ALERT_ONCE) != 0);
         np.set("isClearable", statusBarNotification.isClearable());
-        np.set("appName", appName == null ? packageName : appName);
+        np.set("appName", StringUtils.defaultString(appName, packageName));
         np.set("time", Long.toString(statusBarNotification.getPostTime()));
 
         if (!appDatabase.getPrivacy(packageName, AppDatabase.PrivacyOptions.BLOCK_CONTENTS)) {
@@ -624,9 +624,8 @@ public class NotificationsPlugin extends Plugin implements NotificationReceiver.
         } else {
             String packageName = statusBarNotification.getPackageName();
             int id = statusBarNotification.getId();
-            String safePackageName = (packageName == null) ? "" : packageName;
+            result = StringUtils.defaultString(packageName) + ":" + StringUtils.defaultString(tag) +
-            String safeTag = (tag == null) ? "" : tag;
+                    ":" + id;
-            result = safePackageName + ":" + safeTag + ":" + id;
         }
         return result;
     }