1 files changed, 19 insertions, 6 deletions

diff --git a/media/java/android/mtp/MtpObjectInfo.java b/media/java/android/mtp/MtpObjectInfo.java
index 02092b177fe0..35d8dfbad84a 100644
--- a/media/java/android/mtp/MtpObjectInfo.java
+++ b/media/java/android/mtp/MtpObjectInfo.java
@@ -16,8 +16,13 @@
 
 package android.mtp;
 
+import android.annotation.NonNull;
+import android.os.Build;
+
 import com.android.internal.util.Preconditions;
 
+import dalvik.system.VMRuntime;
+
 /**
  * This class encapsulates information about an object on an MTP device.
  * This corresponds to the ObjectInfo Dataset described in
@@ -40,10 +45,10 @@ public final class MtpObjectInfo {
     private int mAssociationType;
     private int mAssociationDesc;
     private int mSequenceNumber;
-    private String mName;
+    private String mName = "";
     private long mDateCreated;
     private long mDateModified;
-    private String mKeywords;
+    private String mKeywords = "";
 
     // only instantiated via JNI or via a builder
     private MtpObjectInfo() {
@@ -311,7 +316,7 @@ public final class MtpObjectInfo {
      *
      * @return the object's name
      */
-    public final String getName() {
+    public final @NonNull String getName() {
         return mName;
     }
 
@@ -340,7 +345,7 @@ public final class MtpObjectInfo {
      *
      * @return the object's keyword list
      */
-    public final String getKeywords() {
+    public final @NonNull String getKeywords() {
         return mKeywords;
     }
 
@@ -435,12 +440,20 @@ public final class MtpObjectInfo {
             return this;
         }
 
-        public Builder setKeywords(String value) {
+        public Builder setKeywords(@NonNull String value) {
+            if (VMRuntime.getRuntime().getTargetSdkVersion() > Build.VERSION_CODES.N_MR1) {
+                Preconditions.checkNotNull(value);
+            } else if (value == null) {
+                // Before N_MR1 we accept null value and it was regarded as an empty string in
+                // MtpDevice#sendObjectInfo.
+                value = "";
+            }
             mObjectInfo.mKeywords = value;
             return this;
         }
 
-        public Builder setName(String value) {
+        public Builder setName(@NonNull String value) {
+            Preconditions.checkNotNull(value);
             mObjectInfo.mName = value;
             return this;
         }