diff --git a/core/api/test-current.txt b/core/api/test-current.txt
index 20e91873a7e01..35cdd13f7d849 100644
--- a/core/api/test-current.txt
+++ b/core/api/test-current.txt
@@ -656,6 +656,16 @@ package android.app.usage {
     ctor public UsageStats();
   }
 
+  public static final class UsageStats.Builder {
+    ctor public UsageStats.Builder();
+    method @NonNull public android.app.usage.UsageStats build();
+    method @NonNull public android.app.usage.UsageStats.Builder setFirstTimeStamp(long);
+    method @NonNull public android.app.usage.UsageStats.Builder setLastTimeStamp(long);
+    method @NonNull public android.app.usage.UsageStats.Builder setLastTimeUsed(long);
+    method @NonNull public android.app.usage.UsageStats.Builder setPackageName(@Nullable String);
+    method @NonNull public android.app.usage.UsageStats.Builder setTotalTimeInForeground(long);
+  }
+
   public final class UsageStatsManager {
     method public void forceUsageSourceSettingRead();
   }
@@ -1897,6 +1907,16 @@ package android.os.storage {
     method public String getPath();
   }
 
+  public static final class StorageVolume.Builder {
+    ctor public StorageVolume.Builder(@NonNull String, @NonNull java.io.File, @NonNull String, @NonNull android.os.UserHandle, @NonNull String);
+    method @NonNull public android.os.storage.StorageVolume build();
+    method @NonNull public android.os.storage.StorageVolume.Builder setEmulated(boolean);
+    method @NonNull public android.os.storage.StorageVolume.Builder setPrimary(boolean);
+    method @NonNull public android.os.storage.StorageVolume.Builder setRemovable(boolean);
+    method @NonNull public android.os.storage.StorageVolume.Builder setStorageUuid(@Nullable java.util.UUID);
+    method @NonNull public android.os.storage.StorageVolume.Builder setUuid(@Nullable String);
+  }
+
 }
 
 package android.os.strictmode {
diff --git a/core/java/android/app/usage/UsageStats.java b/core/java/android/app/usage/UsageStats.java
index cda4634089550..b723140e2361c 100644
--- a/core/java/android/app/usage/UsageStats.java
+++ b/core/java/android/app/usage/UsageStats.java
@@ -31,6 +31,8 @@ import static android.app.usage.UsageEvents.Event.ROLLOVER_FOREGROUND_SERVICE;
 import static android.app.usage.UsageEvents.Event.USER_INTERACTION;
 
 import android.annotation.CurrentTimeMillisLong;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.annotation.SystemApi;
 import android.annotation.TestApi;
 import android.compat.annotation.UnsupportedAppUsage;
@@ -760,4 +762,48 @@ public final class UsageStats implements Parcelable {
             return new UsageStats[size];
         }
     };
+
+    /** @hide */
+    // This class is used by the mainline test suite, so we have to keep these APIs around across
+    // releases. Consider making this class public to help external developers to write tests as
+    // well.
+    @TestApi
+    public static final class Builder {
+        private final UsageStats mUsageStats = new UsageStats();
+
+        @NonNull
+        public UsageStats build() {
+            return mUsageStats;
+        }
+
+        @NonNull
+        public Builder setPackageName(@Nullable String packageName) {
+            mUsageStats.mPackageName = packageName;
+            return this;
+        }
+
+        @NonNull
+        public Builder setFirstTimeStamp(long firstTimeStamp) {
+            mUsageStats.mBeginTimeStamp = firstTimeStamp;
+            return this;
+        }
+
+        @NonNull
+        public Builder setLastTimeStamp(long lastTimeStamp) {
+            mUsageStats.mEndTimeStamp = lastTimeStamp;
+            return this;
+        }
+
+        @NonNull
+        public Builder setTotalTimeInForeground(long totalTimeInForeground) {
+            mUsageStats.mTotalTimeInForeground = totalTimeInForeground;
+            return this;
+        }
+
+        @NonNull
+        public Builder setLastTimeUsed(long lastTimeUsed) {
+            mUsageStats.mLastTimeUsed = lastTimeUsed;
+            return this;
+        }
+    }
 }
diff --git a/core/java/android/os/storage/StorageVolume.java b/core/java/android/os/storage/StorageVolume.java
index 36177c46ebef1..2adcbc318614a 100644
--- a/core/java/android/os/storage/StorageVolume.java
+++ b/core/java/android/os/storage/StorageVolume.java
@@ -20,6 +20,7 @@ import static android.annotation.SystemApi.Client.MODULE_LIBRARIES;
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
+import android.annotation.SuppressLint;
 import android.annotation.SystemApi;
 import android.annotation.TestApi;
 import android.compat.annotation.UnsupportedAppUsage;
@@ -551,4 +552,82 @@ public final class StorageVolume implements Parcelable {
         parcel.writeString8(mFsUuid);
         parcel.writeString8(mState);
     }
+
+    /** @hide */
+    // This class is used by the mainline test suite, so we have to keep these APIs around across
+    // releases. Consider making this class public to help external developers to write tests as
+    // well.
+    @TestApi
+    public static final class Builder {
+        private String mId;
+        private File mPath;
+        private String mDescription;
+        private boolean mPrimary;
+        private boolean mRemovable;
+        private boolean mEmulated;
+        private UserHandle mOwner;
+        private UUID mStorageUuid;
+        private String mUuid;
+        private String mState;
+
+        @SuppressLint("StreamFiles")
+        public Builder(
+                @NonNull String id, @NonNull File path, @NonNull String description,
+                @NonNull UserHandle owner, @NonNull String state) {
+            mId = id;
+            mPath = path;
+            mDescription = description;
+            mOwner = owner;
+            mState = state;
+        }
+
+        @NonNull
+        public Builder setStorageUuid(@Nullable UUID storageUuid) {
+            mStorageUuid = storageUuid;
+            return this;
+        }
+
+        @NonNull
+        public Builder setUuid(@Nullable String uuid) {
+            mUuid = uuid;
+            return this;
+        }
+
+        @NonNull
+        public Builder setPrimary(boolean primary) {
+            mPrimary = primary;
+            return this;
+        }
+
+        @NonNull
+        public Builder setRemovable(boolean removable) {
+            mRemovable = removable;
+            return this;
+        }
+
+        @NonNull
+        public Builder setEmulated(boolean emulated) {
+            mEmulated = emulated;
+            return this;
+        }
+
+        @NonNull
+        public StorageVolume build() {
+            return new StorageVolume(
+                    mId,
+                    mPath,
+                    /* internalPath= */ mPath,
+                    mDescription,
+                    mPrimary,
+                    mRemovable,
+                    mEmulated,
+                    /* allowMassStorage= */ false,
+                    /* maxFileSize= */ 0,
+                    mOwner,
+                    mStorageUuid,
+                    mUuid,
+                    mState);
+        }
+    }
+
 }