From 737a25b2ea315302fecde010633ca1689788c577 Mon Sep 17 00:00:00 2001
From: Thomas Kuehne <thomas.kuehne@gmx.li>
Date: Mon, 1 Jun 2026 03:44:07 +0000
Subject: [PATCH] InstallHandler: add @Nullable / @NonNull annotations

---
 .../gadgetbridge/devices/GpxRouteInstallHandler.java        | 4 ++--
 .../freeyourgadget/gadgetbridge/devices/InstallHandler.java | 6 +++---
 .../devices/atcbleoepl/ATCBLEOEPLInstallHandler.java        | 4 ++--
 .../gadgetbridge/devices/divoom/PixooInstallHandler.java    | 4 ++--
 .../devices/garmin/GarminFitFileInstallHandler.java         | 4 ++--
 .../devices/garmin/GarminPrgFileInstallHandler.java         | 4 ++--
 .../devices/huami/miband2/MiBand2FWInstallHandler.java      | 4 +++-
 .../devices/huami/zeppos/ZeppOsAgpsInstallHandler.java      | 4 ++--
 .../devices/huami/zeppos/ZeppOsMapsInstallHandler.java      | 4 ++--
 .../devices/huami/zeppos/ZeppOsMusicInstallHandler.java     | 4 ++--
 .../gadgetbridge/devices/huawei/HuaweiInstallHandler.java   | 4 ++--
 .../devices/igpsport/IGPSportRouteInstallHandler.java       | 4 ++--
 .../devices/miband/AbstractMiBandFWInstallHandler.java      | 4 ++--
 .../gadgetbridge/devices/pebble/PBWInstallHandler.java      | 5 ++---
 .../devices/pinetime/PineTimeInstallHandler.java            | 4 ++--
 .../devices/qhybrid/FossilHRInstallHandler.java             | 4 ++--
 .../gadgetbridge/devices/qhybrid/FossilInstallHandler.java  | 4 ++--
 .../devices/thermalprinter/ImageFilePrinterHandler.java     | 4 ++--
 .../gadgetbridge/devices/xiaomi/XiaomiInstallHandler.java   | 4 ++--
 .../service/devices/cmfwatchpro/CmfInstallHandler.java      | 4 ++--
 .../devices/huami/zeppos/ZeppOsFwInstallHandler.java        | 4 ++--
 21 files changed, 44 insertions(+), 43 deletions(-)

diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/GpxRouteInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/GpxRouteInstallHandler.java
index bb38236064..b3b9450a65 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/GpxRouteInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/GpxRouteInstallHandler.java
@@ -74,7 +74,7 @@ public abstract class GpxRouteInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -112,7 +112,7 @@ public abstract class GpxRouteInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
     }
 
     @Nullable
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/InstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/InstallHandler.java
index a996d4f613..ed4e272d32 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/InstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/InstallHandler.java
@@ -1,4 +1,4 @@
-/*  Copyright (C) 2015-2024 Andreas Shimokawa, Carsten Pfeiffer
+/*  Copyright (C) 2015-2026 Andreas Shimokawa, Carsten Pfeiffer, Thomas Kuehne
 
     This file is part of Gadgetbridge.
 
@@ -48,10 +48,10 @@ public interface InstallHandler {
      * @param installActivity the activity to interact with
      * @param device          the device to which the element shall be installed
      */
-    void validateInstallation(InstallActivity installActivity, GBDevice device);
+    void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device);
 
     /**
      * Allows device specific code to be executed just before the installation starts
      */
-    void onStartInstall(GBDevice device);
+    void onStartInstall(@NonNull GBDevice device);
 }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/atcbleoepl/ATCBLEOEPLInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/atcbleoepl/ATCBLEOEPLInstallHandler.java
index 4666ec2484..3bf240de26 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/atcbleoepl/ATCBLEOEPLInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/atcbleoepl/ATCBLEOEPLInstallHandler.java
@@ -49,12 +49,12 @@ public class ATCBLEOEPLInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         installActivity.setInstallEnabled(true);
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
 
     }
 }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/divoom/PixooInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/divoom/PixooInstallHandler.java
index c45d79caf3..6f1b3441ce 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/divoom/PixooInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/divoom/PixooInstallHandler.java
@@ -66,12 +66,12 @@ public class PixooInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         installActivity.setInstallEnabled(true);
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
 
     }
 }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminFitFileInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminFitFileInstallHandler.java
index 335871b863..09c8c59c9e 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminFitFileInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminFitFileInstallHandler.java
@@ -128,7 +128,7 @@ public class GarminFitFileInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (fitParseException != null) {
             installActivity.setInfoText(fitParseException.getLocalizedMessage());
             installActivity.setInstallEnabled(false);
@@ -170,7 +170,7 @@ public class GarminFitFileInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
     }
 
     public byte[] getRawBytes() {
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminPrgFileInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminPrgFileInstallHandler.java
index 2da73a00c9..215f2f0d03 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminPrgFileInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/garmin/GarminPrgFileInstallHandler.java
@@ -58,7 +58,7 @@ public class GarminPrgFileInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -115,7 +115,7 @@ public class GarminPrgFileInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
     }
 
     public byte[] getRawBytes() {
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/miband2/MiBand2FWInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/miband2/MiBand2FWInstallHandler.java
index b7a29bce5f..7972867abd 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/miband2/MiBand2FWInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/miband2/MiBand2FWInstallHandler.java
@@ -19,6 +19,8 @@ package nodomain.freeyourgadget.gadgetbridge.devices.huami.miband2;
 import android.content.Context;
 import android.net.Uri;
 
+import androidx.annotation.NonNull;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -42,7 +44,7 @@ public class MiBand2FWInstallHandler extends AbstractMiBandFWInstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         super.validateInstallation(installActivity, device);
         maybeAddFw53Hint(installActivity, device);
         maybeAddFontHint(installActivity);
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsAgpsInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsAgpsInstallHandler.java
index f497b9f0cc..cec0e5ede5 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsAgpsInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsAgpsInstallHandler.java
@@ -87,7 +87,7 @@ public class ZeppOsAgpsInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -134,7 +134,7 @@ public class ZeppOsAgpsInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
     }
 
     public ZeppOsAgpsFile getFile() {
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMapsInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMapsInstallHandler.java
index cb0e7a344f..a51cd7d5b1 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMapsInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMapsInstallHandler.java
@@ -58,7 +58,7 @@ public class ZeppOsMapsInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -101,7 +101,7 @@ public class ZeppOsMapsInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
     }
 
     public ZeppOsMapsFile getFile() {
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMusicInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMusicInstallHandler.java
index 71c58e1d14..c3f58d7d9d 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMusicInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huami/zeppos/ZeppOsMusicInstallHandler.java
@@ -69,7 +69,7 @@ public class ZeppOsMusicInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -104,7 +104,7 @@ public class ZeppOsMusicInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
     }
 
     public AudioInfo getAudioInfo() {
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiInstallHandler.java
index 9c8f7ecd29..0980e9e073 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/huawei/HuaweiInstallHandler.java
@@ -110,7 +110,7 @@ public class HuaweiInstallHandler implements InstallHandler {
 
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         final HuaweiState huaweiDeviceState = HuaweiDeviceStateManager.get(device);
 
         if (helper.isFirmware) {
@@ -304,7 +304,7 @@ public class HuaweiInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
         helper.unsetFwBytes();
     }
 }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/igpsport/IGPSportRouteInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/igpsport/IGPSportRouteInstallHandler.java
index c88c9226be..d9adee768a 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/igpsport/IGPSportRouteInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/igpsport/IGPSportRouteInstallHandler.java
@@ -97,7 +97,7 @@ public class IGPSportRouteInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -138,7 +138,7 @@ public class IGPSportRouteInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
 
     }
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/AbstractMiBandFWInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/AbstractMiBandFWInstallHandler.java
index c9a8aff440..fe36dacaac 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/AbstractMiBandFWInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/miband/AbstractMiBandFWInstallHandler.java
@@ -80,7 +80,7 @@ public abstract class AbstractMiBandFWInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -147,7 +147,7 @@ public abstract class AbstractMiBandFWInstallHandler implements InstallHandler {
     protected abstract boolean isSupportedDeviceType(GBDevice device);
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
 
     }
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWInstallHandler.java
index dea34e55c8..385dc50235 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pebble/PBWInstallHandler.java
@@ -46,7 +46,6 @@ import nodomain.freeyourgadget.gadgetbridge.impl.GBDeviceApp;
 import nodomain.freeyourgadget.gadgetbridge.model.DeviceType;
 import nodomain.freeyourgadget.gadgetbridge.model.GenericItem;
 import nodomain.freeyourgadget.gadgetbridge.util.FileUtils;
-import nodomain.freeyourgadget.gadgetbridge.devices.pebble.PebbleHardware;
 import nodomain.freeyourgadget.gadgetbridge.util.PebbleUtils;
 import nodomain.freeyourgadget.gadgetbridge.deviceevents.GBDeviceEventVersionInfo;
 
@@ -63,7 +62,7 @@ public class PBWInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -162,7 +161,7 @@ public class PBWInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
         if (mPBWReader.isFirmware() || mPBWReader.isLanguage()) {
             return;
         }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pinetime/PineTimeInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pinetime/PineTimeInstallHandler.java
index 2ef19d7679..6cacf48b47 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pinetime/PineTimeInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/pinetime/PineTimeInstallHandler.java
@@ -92,7 +92,7 @@ public class PineTimeInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         installActivity.setInstallEnabled(true);
 
         if (device.isBusy()) {
@@ -131,7 +131,7 @@ public class PineTimeInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
     }
 
     @NonNull
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilHRInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilHRInstallHandler.java
index 395456aafb..123198aff2 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilHRInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilHRInstallHandler.java
@@ -68,7 +68,7 @@ public class FossilHRInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -106,7 +106,7 @@ public class FossilHRInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
         DeviceCoordinator mCoordinator = device.getDeviceCoordinator();
         LocalBroadcastManager manager = LocalBroadcastManager.getInstance(mContext);
         manager.sendBroadcast(new Intent(GB.ACTION_SET_PROGRESS_BAR).putExtra(GB.PROGRESS_BAR_INDETERMINATE, true));
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilInstallHandler.java
index 6f43d86ed7..2698965c67 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/qhybrid/FossilInstallHandler.java
@@ -82,7 +82,7 @@ public class FossilInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -105,7 +105,7 @@ public class FossilInstallHandler implements InstallHandler {
 
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
     }
 
     @NonNull
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/thermalprinter/ImageFilePrinterHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/thermalprinter/ImageFilePrinterHandler.java
index 6e2a1582df..de033b940e 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/thermalprinter/ImageFilePrinterHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/thermalprinter/ImageFilePrinterHandler.java
@@ -56,13 +56,13 @@ public class ImageFilePrinterHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         installActivity.setPreview(incomingBitmap);
         installActivity.setInstallEnabled(true);
     }
 
     @Override
-    public void onStartInstall(GBDevice device) {
+    public void onStartInstall(@NonNull GBDevice device) {
 
     }
 }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/xiaomi/XiaomiInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/xiaomi/XiaomiInstallHandler.java
index f317eeafaa..4e8d68ddb4 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/xiaomi/XiaomiInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/devices/xiaomi/XiaomiInstallHandler.java
@@ -53,7 +53,7 @@ public class XiaomiInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -100,7 +100,7 @@ public class XiaomiInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
         helper.unsetFwBytes(); // free up memory
     }
 }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/cmfwatchpro/CmfInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/cmfwatchpro/CmfInstallHandler.java
index 671faeba91..e7440fcda0 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/cmfwatchpro/CmfInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/cmfwatchpro/CmfInstallHandler.java
@@ -52,7 +52,7 @@ public class CmfInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(final InstallActivity installActivity, final GBDevice device) {
+    public void validateInstallation(@NonNull final InstallActivity installActivity, @NonNull final GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -94,7 +94,7 @@ public class CmfInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
         helper.unsetFwBytes(); // free up memory
     }
 }
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huami/zeppos/ZeppOsFwInstallHandler.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huami/zeppos/ZeppOsFwInstallHandler.java
index 99359df57e..c00f198fbb 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huami/zeppos/ZeppOsFwInstallHandler.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/huami/zeppos/ZeppOsFwInstallHandler.java
@@ -75,7 +75,7 @@ public class ZeppOsFwInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void validateInstallation(InstallActivity installActivity, GBDevice device) {
+    public void validateInstallation(@NonNull InstallActivity installActivity, @NonNull GBDevice device) {
         if (device.isBusy()) {
             installActivity.setInfoText(device.getBusyTask());
             installActivity.setInstallEnabled(false);
@@ -132,7 +132,7 @@ public class ZeppOsFwInstallHandler implements InstallHandler {
     }
 
     @Override
-    public void onStartInstall(final GBDevice device) {
+    public void onStartInstall(@NonNull final GBDevice device) {
         final boolean shouldCache = mHelper.getFirmwareType().isApp() || mHelper.getFirmwareType().isWatchface();
         if (shouldCache) {
             saveToCache(device);