diff --git a/services/core/jni/BroadcastRadio/NativeCallbackThread.h b/services/core/jni/BroadcastRadio/NativeCallbackThread.h
index 53990be065354..0f62de9c39dfd 100644
--- a/services/core/jni/BroadcastRadio/NativeCallbackThread.h
+++ b/services/core/jni/BroadcastRadio/NativeCallbackThread.h
@@ -41,7 +41,7 @@ class NativeCallbackThread {
     DISALLOW_COPY_AND_ASSIGN(NativeCallbackThread);
 
 public:
-    NativeCallbackThread(JavaVM *vm);
+    explicit NativeCallbackThread(JavaVM *vm);
     virtual ~NativeCallbackThread();
 
     void enqueue(const Task &task);
diff --git a/services/core/jni/BroadcastRadio/Tuner.cpp b/services/core/jni/BroadcastRadio/Tuner.cpp
index 9c2e1e59dd32b..a2a7f7d9645d0 100644
--- a/services/core/jni/BroadcastRadio/Tuner.cpp
+++ b/services/core/jni/BroadcastRadio/Tuner.cpp
@@ -73,7 +73,8 @@ class HalDeathRecipient : public hidl_death_recipient {
     wp<V1_1::ITunerCallback> mTunerCallback;
 
 public:
-    HalDeathRecipient(wp<V1_1::ITunerCallback> tunerCallback):mTunerCallback(tunerCallback) {}
+    explicit HalDeathRecipient(wp<V1_1::ITunerCallback> tunerCallback)
+        : mTunerCallback(tunerCallback) {}
 
     virtual void serviceDied(uint64_t cookie, const wp<hidl::base::V1_0::IBase>& who);
 };
diff --git a/services/core/jni/com_android_server_hdmi_HdmiCecController.cpp b/services/core/jni/com_android_server_hdmi_HdmiCecController.cpp
index c22109c7816a2..b08d13f234ced 100644
--- a/services/core/jni/com_android_server_hdmi_HdmiCecController.cpp
+++ b/services/core/jni/com_android_server_hdmi_HdmiCecController.cpp
@@ -89,7 +89,7 @@ public:
 private:
     class HdmiCecCallback : public IHdmiCecCallback {
     public:
-        HdmiCecCallback(HdmiCecController* controller) : mController(controller) {};
+        explicit HdmiCecCallback(HdmiCecController* controller) : mController(controller) {};
         Return<void> onCecMessage(const CecMessage& event)  override;
         Return<void> onHotplugEvent(const HotplugEvent& event)  override;
     private:
diff --git a/services/core/jni/com_android_server_storage_AppFuseBridge.cpp b/services/core/jni/com_android_server_storage_AppFuseBridge.cpp
index c8f842dde7ae5..e51963340ae14 100644
--- a/services/core/jni/com_android_server_storage_AppFuseBridge.cpp
+++ b/services/core/jni/com_android_server_storage_AppFuseBridge.cpp
@@ -74,7 +74,7 @@ public:
         }
     }
 
-    operator bool() {
+    explicit operator bool() {
         return mLocked;
     }
 
diff --git a/services/core/jni/com_android_server_tv_TvInputHal.cpp b/services/core/jni/com_android_server_tv_TvInputHal.cpp
index 6c2a894a3a6af..098b2ef6439dd 100644
--- a/services/core/jni/com_android_server_tv_TvInputHal.cpp
+++ b/services/core/jni/com_android_server_tv_TvInputHal.cpp
@@ -292,7 +292,7 @@ private:
 
     class TvInputCallback : public ITvInputCallback {
     public:
-        TvInputCallback(JTvInputHal* hal);
+        explicit TvInputCallback(JTvInputHal* hal);
         Return<void> notify(const TvInputEvent& event) override;
     private:
         JTvInputHal* mHal;