diff --git a/libwvdrmengine/aidl_include/WVDrmFactory.h b/libwvdrmengine/aidl_include/WVDrmFactory.h
index 7dcf0a00..3c839f80 100644
--- a/libwvdrmengine/aidl_include/WVDrmFactory.h
+++ b/libwvdrmengine/aidl_include/WVDrmFactory.h
@@ -19,7 +19,8 @@ namespace hardware {
 namespace drm {
 namespace widevine {
 
-struct WVDrmFactory : public ::aidl::android::hardware::drm::BnDrmFactory {
+class WVDrmFactory : public ::aidl::android::hardware::drm::BnDrmFactory {
+ public:
   WVDrmFactory() {}
   virtual ~WVDrmFactory() {}
 
diff --git a/libwvdrmengine/build_all_unit_tests.sh b/libwvdrmengine/build_all_unit_tests.sh
index 1daa8cde..42636f0f 100755
--- a/libwvdrmengine/build_all_unit_tests.sh
+++ b/libwvdrmengine/build_all_unit_tests.sh
@@ -52,7 +52,7 @@ WV_UNITTESTS="base64_test \
      file_store_unittest \
      file_utils_unittest \
      generic_crypto_unittest \
-     hidl_metrics_adapter_unittest \
+     hal_metrics_adapter_unittest \
      http_socket_test \
      initialization_data_unittest \
      keybox_ota_test \
diff --git a/libwvdrmengine/mediacrypto/aidl_include/WVCryptoPlugin.h b/libwvdrmengine/mediacrypto/aidl_include/WVCryptoPlugin.h
index b3f9a5d6..96c4e1c4 100644
--- a/libwvdrmengine/mediacrypto/aidl_include/WVCryptoPlugin.h
+++ b/libwvdrmengine/mediacrypto/aidl_include/WVCryptoPlugin.h
@@ -23,14 +23,21 @@ namespace hardware {
 namespace drm {
 namespace widevine {
 
-struct SharedBufferBase {
-  uint8_t* mBase;
-  int64_t mSize;
+class SharedBufferBase {
+ public:
   SharedBufferBase(const ::aidl::android::hardware::drm::SharedBuffer& mem);
   ~SharedBufferBase();
+  uint8_t* base() const { return mBase; }
+  int64_t size() const { return mSize; }
+  void set_base(uint8_t* base) { mBase = base; }
+  void set_size(uint64_t size) { mSize = size; }
+ private:
+  uint8_t* mBase;
+  int64_t mSize;
 };
 
-struct WVCryptoPlugin : public ::aidl::android::hardware::drm::BnCryptoPlugin {
+class WVCryptoPlugin : public ::aidl::android::hardware::drm::BnCryptoPlugin {
+ public:
   WVCryptoPlugin(const void* data, size_t size,
                  const ::android::sp<wvcdm::WvContentDecryptionModule>& cdm);
   virtual ~WVCryptoPlugin();
diff --git a/libwvdrmengine/mediacrypto/aidl_src/WVCryptoPlugin.cpp b/libwvdrmengine/mediacrypto/aidl_src/WVCryptoPlugin.cpp
index d2f4ab49..fffda83f 100644
--- a/libwvdrmengine/mediacrypto/aidl_src/WVCryptoPlugin.cpp
+++ b/libwvdrmengine/mediacrypto/aidl_src/WVCryptoPlugin.cpp
@@ -64,8 +64,9 @@ WVCryptoPlugin::~WVCryptoPlugin() {
 }
 
 SharedBufferBase::SharedBufferBase(
-    const ::aidl::android::hardware::drm::SharedBuffer& mem)
-    : mBase(nullptr), mSize(mem.size) {
+    const ::aidl::android::hardware::drm::SharedBuffer& mem) {
+  set_base(nullptr);
+  set_size(mem.size);
   if (mem.handle.fds.empty()) {
     return;
   }
@@ -75,13 +76,13 @@ SharedBufferBase::SharedBufferBase(
   if (addr == MAP_FAILED) {
     ALOGE("mmap err: fd %d; errno %s", fd, strerror(errno));
   } else {
-    mBase = static_cast<uint8_t*>(addr);
+    set_base(static_cast<uint8_t*>(addr));
   }
 }
 
 SharedBufferBase::~SharedBufferBase() {
-  if (munmap(mBase, mSize)) {
-    ALOGE("munmap err: base %p; errno %s", mBase, strerror(errno));
+  if (munmap(base(), size())) {
+    ALOGE("munmap err: base %p; errno %s", base(), strerror(errno));
   }
 }
 
@@ -183,7 +184,7 @@ SharedBufferBase::~SharedBufferBase() {
     }
 
     auto src = mSharedBufferMap[in_args.source.bufferId];
-    if (src->mBase == nullptr) {
+    if (src->base() == nullptr) {
       detailedError = "source is a nullptr";
       return toNdkScopedAStatus(Status::ERROR_DRM_CANNOT_HANDLE, detailedError);
     }
@@ -193,18 +194,18 @@ SharedBufferBase::~SharedBufferBase() {
                                &totalSrcSize) ||
         __builtin_add_overflow(totalSrcSize, in_args.source.size,
                                &totalSrcSize) ||
-        totalSrcSize > src->mSize) {
+        totalSrcSize > src->size()) {
       android_errorWriteLog(0x534e4554, "176496160");
       detailedError = "invalid source buffer size";
       return toNdkScopedAStatus(Status::ERROR_DRM_CANNOT_HANDLE, detailedError);
     }
 
-    srcPtr = src->mBase + in_args.source.offset + in_args.offset;
+    srcPtr = src->base() + in_args.source.offset + in_args.offset;
 
     if (in_args.destination.getTag() == NON_SECURE) {
       const SharedBuffer& destBuffer = in_args.destination.get<NON_SECURE>();
       auto dest = mSharedBufferMap[destBuffer.bufferId];
-      if (dest->mBase == nullptr) {
+      if (dest->base() == nullptr) {
         detailedError = "destination is a nullptr";
         return toNdkScopedAStatus(Status::ERROR_DRM_CANNOT_HANDLE,
                                   detailedError);
@@ -212,14 +213,14 @@ SharedBufferBase::~SharedBufferBase() {
       size_t totalDstSize = 0;
       if (__builtin_add_overflow(destBuffer.offset, destBuffer.size,
                                  &totalDstSize) ||
-          totalDstSize > dest->mSize) {
+          totalDstSize > dest->size()) {
         android_errorWriteLog(0x534e4554, "176444622");
         detailedError = "invalid buffer size";
         return toNdkScopedAStatus(Status::ERROR_DRM_FRAME_TOO_LARGE,
                                   detailedError);
       }
       destPtr = static_cast<void*>(
-          dest->mBase + in_args.destination.get<NON_SECURE>().offset);
+          dest->base() + in_args.destination.get<NON_SECURE>().offset);
     } else if (in_args.destination.getTag() == SECURE) {
       handle = android::makeFromAidl(in_args.destination.get<SECURE>());
       destPtr = static_cast<void*>(handle);
diff --git a/libwvdrmengine/mediadrm/aidl_include/WVDrmPlugin.h b/libwvdrmengine/mediadrm/aidl_include/WVDrmPlugin.h
index a66c1a52..f101841a 100644
--- a/libwvdrmengine/mediadrm/aidl_include/WVDrmPlugin.h
+++ b/libwvdrmengine/mediadrm/aidl_include/WVDrmPlugin.h
@@ -40,8 +40,9 @@ using wvcdm::WvContentDecryptionModule;
 const OEMCrypto_Algorithm kInvalidCryptoAlgorithm =
     static_cast<OEMCrypto_Algorithm>(-1);
 
-struct WVDrmPlugin : public ::aidl::android::hardware::drm::BnDrmPlugin,
+class WVDrmPlugin : public ::aidl::android::hardware::drm::BnDrmPlugin,
                      wvcdm::WvCdmEventListener {
+ public:
   WVDrmPlugin(const android::sp<WvContentDecryptionModule>& cdm,
               const std::string& appPackageName,
               WVGenericCryptoInterface* crypto, bool useSpoid);