1 files changed, 29 insertions, 12 deletions

diff --git a/android/hardware/location/ContextHubClient.java b/android/hardware/location/ContextHubClient.java
index 52527ed6..0a21083a 100644
--- a/android/hardware/location/ContextHubClient.java
+++ b/android/hardware/location/ContextHubClient.java
@@ -15,9 +15,13 @@
  */
 package android.hardware.location;
 
+import android.annotation.NonNull;
 import android.annotation.RequiresPermission;
+import android.annotation.SystemApi;
 import android.os.RemoteException;
 
+import com.android.internal.util.Preconditions;
+
 import dalvik.system.CloseGuard;
 
 import java.io.Closeable;
@@ -31,16 +35,12 @@ import java.util.concurrent.atomic.AtomicBoolean;
  *
  * @hide
  */
+@SystemApi
 public class ContextHubClient implements Closeable {
     /*
      * The proxy to the client interface at the service.
      */
-    private final IContextHubClient mClientProxy;
-
-    /*
-     * The callback interface associated with this client.
-     */
-    private final IContextHubClientCallback mCallbackInterface;
+    private IContextHubClient mClientProxy = null;
 
     /*
      * The Context Hub that this client is attached to.
@@ -51,20 +51,33 @@ public class ContextHubClient implements Closeable {
 
     private final AtomicBoolean mIsClosed = new AtomicBoolean(false);
 
-    /* package */ ContextHubClient(
-            IContextHubClient clientProxy, IContextHubClientCallback callback,
-            ContextHubInfo hubInfo) {
-        mClientProxy = clientProxy;
-        mCallbackInterface = callback;
+    /* package */ ContextHubClient(ContextHubInfo hubInfo) {
         mAttachedHub = hubInfo;
         mCloseGuard.open("close");
     }
 
     /**
+     * Sets the proxy interface of the client at the service. This method should always be called
+     * by the ContextHubManager after the client is registered at the service, and should only be
+     * called once.
+     *
+     * @param clientProxy the proxy of the client at the service
+     */
+    /* package */ void setClientProxy(IContextHubClient clientProxy) {
+        Preconditions.checkNotNull(clientProxy, "IContextHubClient cannot be null");
+        if (mClientProxy != null) {
+            throw new IllegalStateException("Cannot change client proxy multiple times");
+        }
+
+        mClientProxy = clientProxy;
+    }
+
+    /**
      * Returns the hub that this client is attached to.
      *
      * @return the ContextHubInfo of the attached hub
      */
+    @NonNull
     public ContextHubInfo getAttachedHub() {
         return mAttachedHub;
     }
@@ -96,12 +109,16 @@ public class ContextHubClient implements Closeable {
      *
      * @return the result of sending the message defined as in ContextHubTransaction.Result
      *
+     * @throws NullPointerException if NanoAppMessage is null
+     *
      * @see NanoAppMessage
      * @see ContextHubTransaction.Result
      */
     @RequiresPermission(android.Manifest.permission.LOCATION_HARDWARE)
     @ContextHubTransaction.Result
-    public int sendMessageToNanoApp(NanoAppMessage message) {
+    public int sendMessageToNanoApp(@NonNull NanoAppMessage message) {
+        Preconditions.checkNotNull(message, "NanoAppMessage cannot be null");
+
         try {
             return mClientProxy.sendMessageToNanoApp(message);
         } catch (RemoteException e) {