diff --git a/drm/drmserver/DrmManager.cpp b/drm/drmserver/DrmManager.cpp
index f7989bd..9b27737 100644
--- a/drm/drmserver/DrmManager.cpp
+++ b/drm/drmserver/DrmManager.cpp
@@ -127,7 +127,7 @@
         }
     }
 
-    if (!mimeType.isEmpty()) {
+    if (!mimeType.empty()) {
         metrics.mMimeTypes.insert(mimeType.c_str());
     } else if (NULL != info) {
         DrmSupportInfo::MimeTypeIterator mimeIter = info->getMimeTypeIterator();
@@ -395,7 +395,7 @@
         IDrmEngine& rDrmEngine = mPlugInManager.getPlugIn(plugInId);
         mimeType = rDrmEngine.getOriginalMimeType(uniqueId, path, fd);
     }
-    if (!mimeType.isEmpty()) {
+    if (!mimeType.empty()) {
         recordEngineMetrics(__func__, plugInId, mimeType);
     }
     return mimeType;
diff --git a/drm/libmediadrm/DrmHalAidl.cpp b/drm/libmediadrm/DrmHalAidl.cpp
index 9e30708..7106d66 100644
--- a/drm/libmediadrm/DrmHalAidl.cpp
+++ b/drm/libmediadrm/DrmHalAidl.cpp
@@ -375,7 +375,7 @@
     sp<DrmHalAidl> drm = mDrm.promote();
     if (drm == NULL) {
         name.append("<deleted>");
-    } else if (drm->getPropertyStringInternal(String8("vendor"), name) != OK || name.isEmpty()) {
+    } else if (drm->getPropertyStringInternal(String8("vendor"), name) != OK || name.empty()) {
         name.append("<Get vendor failed or is empty>");
     }
     name.append("[");
@@ -947,12 +947,12 @@
 
     String8 vendor;
     String8 description;
-    if (getPropertyStringInternal(String8("vendor"), vendor) != OK || vendor.isEmpty()) {
+    if (getPropertyStringInternal(String8("vendor"), vendor) != OK || vendor.empty()) {
         ALOGE("Get vendor failed or is empty");
         vendor = "NONE";
     }
     if (getPropertyStringInternal(String8("description"), description) != OK ||
-        description.isEmpty()) {
+        description.empty()) {
         ALOGE("Get description failed or is empty.");
         description = "NONE";
     }
diff --git a/drm/libmediadrm/DrmHalHidl.cpp b/drm/libmediadrm/DrmHalHidl.cpp
index 29dde96..9317345 100644
--- a/drm/libmediadrm/DrmHalHidl.cpp
+++ b/drm/libmediadrm/DrmHalHidl.cpp
@@ -273,7 +273,7 @@
     sp<DrmHalHidl> drm = mDrm.promote();
     if (drm == NULL) {
         name.append("<deleted>");
-    } else if (drm->getPropertyStringInternal(String8("vendor"), name) != OK || name.isEmpty()) {
+    } else if (drm->getPropertyStringInternal(String8("vendor"), name) != OK || name.empty()) {
         name.append("<Get vendor failed or is empty>");
     }
     name.append("[");
@@ -1261,12 +1261,12 @@
     if (mPluginV1_1 != NULL) {
         String8 vendor;
         String8 description;
-        if (getPropertyStringInternal(String8("vendor"), vendor) != OK || vendor.isEmpty()) {
+        if (getPropertyStringInternal(String8("vendor"), vendor) != OK || vendor.empty()) {
             ALOGE("Get vendor failed or is empty");
             vendor = "NONE";
         }
         if (getPropertyStringInternal(String8("description"), description) != OK ||
-            description.isEmpty()) {
+            description.empty()) {
             ALOGE("Get description failed or is empty.");
             description = "NONE";
         }
diff --git a/drm/mediacas/plugins/clearkey/ClearKeyCasPlugin.cpp b/drm/mediacas/plugins/clearkey/ClearKeyCasPlugin.cpp
index 37051d5..c364bbb 100644
--- a/drm/mediacas/plugins/clearkey/ClearKeyCasPlugin.cpp
+++ b/drm/mediacas/plugins/clearkey/ClearKeyCasPlugin.cpp
@@ -131,7 +131,7 @@
     for (size_t i = 0; i < array.size(); i++) {
         result.appendFormat("%02x ", array[i]);
     }
-    if (result.isEmpty()) {
+    if (result.empty()) {
         result.append("(null)");
     }
     return result;
diff --git a/drm/mediacas/plugins/clearkey/JsonAssetLoader.cpp b/drm/mediacas/plugins/clearkey/JsonAssetLoader.cpp
index a54ae47..07de1d2 100644
--- a/drm/mediacas/plugins/clearkey/JsonAssetLoader.cpp
+++ b/drm/mediacas/plugins/clearkey/JsonAssetLoader.cpp
@@ -187,7 +187,7 @@
  */
 bool JsonAssetLoader::parseJsonAssetString(const String8& jsonAsset,
         Vector<String8>* jsonObjects) {
-    if (jsonAsset.isEmpty()) {
+    if (jsonAsset.empty()) {
         ALOGE("Empty JSON Web Key");
         return false;
     }
diff --git a/drm/mediacas/plugins/mock/MockCasPlugin.cpp b/drm/mediacas/plugins/mock/MockCasPlugin.cpp
index 671fba1..cbff6cb 100644
--- a/drm/mediacas/plugins/mock/MockCasPlugin.cpp
+++ b/drm/mediacas/plugins/mock/MockCasPlugin.cpp
@@ -96,7 +96,7 @@
     for (size_t i = 0; i < array.size(); i++) {
         result.appendFormat("%02x ", array[i]);
     }
-    if (result.isEmpty()) {
+    if (result.empty()) {
         result.append("(null)");
     }
     return result;
diff --git a/drm/mediadrm/plugins/clearkey/default/JsonWebKey.cpp b/drm/mediadrm/plugins/clearkey/default/JsonWebKey.cpp
index a12b1d1..6db70c1 100644
--- a/drm/mediadrm/plugins/clearkey/default/JsonWebKey.cpp
+++ b/drm/mediadrm/plugins/clearkey/default/JsonWebKey.cpp
@@ -77,7 +77,7 @@
             return false;
 
         if (findKey(mJsonObjects[i], &encodedKeyId, &encodedKey)) {
-            if (encodedKeyId.isEmpty() || encodedKey.isEmpty()) {
+            if (encodedKeyId.empty() || encodedKey.empty()) {
                 ALOGE("Must have both key id and key in the JsonWebKey set.");
                 continue;
             }
@@ -225,7 +225,7 @@
  */
 bool JsonWebKey::parseJsonWebKeySet(const String8& jsonWebKeySet,
         Vector<String8>* jsonObjects) {
-    if (jsonWebKeySet.isEmpty()) {
+    if (jsonWebKeySet.empty()) {
         ALOGE("Empty JSON Web Key");
         return false;
     }