Allow sample rate UNSPECIFIED to mean a route-dependent value

Bug: 25641253
Bug: 21019153
Change-Id: I3b8e01b6ea09f42c813ab1a0f3f625dc3803cc0b
diff --git a/api/current.txt b/api/current.txt
index 691ec04a..bb2c332 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -19772,6 +19772,7 @@
     field public static final int ENCODING_PCM_16BIT = 2; // 0x2
     field public static final int ENCODING_PCM_8BIT = 3; // 0x3
     field public static final int ENCODING_PCM_FLOAT = 4; // 0x4
+    field public static final int SAMPLE_RATE_UNSPECIFIED = 0; // 0x0
   }
 
   public static class AudioFormat.Builder {
diff --git a/api/system-current.txt b/api/system-current.txt
index 2374f01..defb4c5 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -21268,6 +21268,7 @@
     field public static final int ENCODING_PCM_16BIT = 2; // 0x2
     field public static final int ENCODING_PCM_8BIT = 3; // 0x3
     field public static final int ENCODING_PCM_FLOAT = 4; // 0x4
+    field public static final int SAMPLE_RATE_UNSPECIFIED = 0; // 0x0
   }
 
   public static class AudioFormat.Builder {
diff --git a/api/test-current.txt b/api/test-current.txt
index a86be54..da6fa6c 100644
--- a/api/test-current.txt
+++ b/api/test-current.txt
@@ -19781,6 +19781,7 @@
     field public static final int ENCODING_PCM_16BIT = 2; // 0x2
     field public static final int ENCODING_PCM_8BIT = 3; // 0x3
     field public static final int ENCODING_PCM_FLOAT = 4; // 0x4
+    field public static final int SAMPLE_RATE_UNSPECIFIED = 0; // 0x0
   }
 
   public static class AudioFormat.Builder {
diff --git a/core/jni/android_media_AudioRecord.cpp b/core/jni/android_media_AudioRecord.cpp
index d0326f1..6904fda 100644
--- a/core/jni/android_media_AudioRecord.cpp
+++ b/core/jni/android_media_AudioRecord.cpp
@@ -180,9 +180,13 @@
 // ----------------------------------------------------------------------------
 static jint
 android_media_AudioRecord_setup(JNIEnv *env, jobject thiz, jobject weak_this,
-        jobject jaa, jint sampleRateInHertz, jint channelMask, jint channelIndexMask,
+        jobject jaa, jintArray jSampleRate, jint channelMask, jint channelIndexMask,
         jint audioFormat, jint buffSizeInBytes, jintArray jSession, jstring opPackageName)
 {
+    jint elements[1];
+    env->GetIntArrayRegion(jSampleRate, 0, 1, elements);
+    int sampleRateInHertz = elements[0];
+
     //ALOGV(">> Entering android_media_AudioRecord_setup");
     //ALOGV("sampleRate=%d, audioFormat=%d, channel mask=%x, buffSizeInBytes=%d",
     //     sampleRateInHertz, audioFormat, channelMask, buffSizeInBytes);
@@ -304,6 +308,11 @@
     env->ReleasePrimitiveArrayCritical(jSession, nSession, 0);
     nSession = NULL;
 
+    {
+        const jint elements[1] = { (jint) lpRecorder->getSampleRate() };
+        env->SetIntArrayRegion(jSampleRate, 0, 1, elements);
+    }
+
     {   // scope for the lock
         Mutex::Autolock l(sLock);
         sAudioRecordCallBackCookies.add(lpCallbackData);
@@ -717,7 +726,7 @@
     // name,               signature,  funcPtr
     {"native_start",         "(II)I",    (void *)android_media_AudioRecord_start},
     {"native_stop",          "()V",    (void *)android_media_AudioRecord_stop},
-    {"native_setup",         "(Ljava/lang/Object;Ljava/lang/Object;IIIII[ILjava/lang/String;)I",
+    {"native_setup",         "(Ljava/lang/Object;Ljava/lang/Object;[IIIII[ILjava/lang/String;)I",
                                        (void *)android_media_AudioRecord_setup},
     {"native_finalize",      "()V",    (void *)android_media_AudioRecord_finalize},
     {"native_release",       "()V",    (void *)android_media_AudioRecord_release},
diff --git a/core/jni/android_media_AudioTrack.cpp b/core/jni/android_media_AudioTrack.cpp
index 1ab9504..84cc185 100644
--- a/core/jni/android_media_AudioTrack.cpp
+++ b/core/jni/android_media_AudioTrack.cpp
@@ -215,9 +215,13 @@
 static jint
 android_media_AudioTrack_setup(JNIEnv *env, jobject thiz, jobject weak_this,
         jobject jaa,
-        jint sampleRateInHertz, jint channelPositionMask, jint channelIndexMask,
+        jintArray jSampleRate, jint channelPositionMask, jint channelIndexMask,
         jint audioFormat, jint buffSizeInBytes, jint memoryMode, jintArray jSession) {
 
+    jint elements[1];
+    env->GetIntArrayRegion(jSampleRate, 0, 1, elements);
+    int sampleRateInHertz = elements[0];
+
     ALOGV("sampleRate=%d, channel mask=%x, index mask=%x, audioFormat(Java)=%d, buffSize=%d",
         sampleRateInHertz, channelPositionMask, channelIndexMask, audioFormat, buffSizeInBytes);
 
@@ -370,6 +374,11 @@
     env->ReleasePrimitiveArrayCritical(jSession, nSession, 0);
     nSession = NULL;
 
+    {
+        const jint elements[1] = { (jint) lpTrack->getSampleRate() };
+        env->SetIntArrayRegion(jSampleRate, 0, 1, elements);
+    }
+
     {   // scope for the lock
         Mutex::Autolock l(sLock);
         sAudioTrackCallBackCookies.add(&lpJniStorage->mCallbackData);
@@ -1114,7 +1123,7 @@
     {"native_stop",          "()V",      (void *)android_media_AudioTrack_stop},
     {"native_pause",         "()V",      (void *)android_media_AudioTrack_pause},
     {"native_flush",         "()V",      (void *)android_media_AudioTrack_flush},
-    {"native_setup",     "(Ljava/lang/Object;Ljava/lang/Object;IIIIII[I)I",
+    {"native_setup",     "(Ljava/lang/Object;Ljava/lang/Object;[IIIIII[I)I",
                                          (void *)android_media_AudioTrack_setup},
     {"native_finalize",      "()V",      (void *)android_media_AudioTrack_finalize},
     {"native_release",       "()V",      (void *)android_media_AudioTrack_release},
diff --git a/media/java/android/media/AudioFormat.java b/media/java/android/media/AudioFormat.java
index 22f4f04..a0dfaa0f 100644
--- a/media/java/android/media/AudioFormat.java
+++ b/media/java/android/media/AudioFormat.java
@@ -335,6 +335,24 @@
             CHANNEL_OUT_LOW_FREQUENCY);
     // CHANNEL_OUT_ALL is not yet defined; if added then it should match AUDIO_CHANNEL_OUT_ALL
 
+    /** Minimum value for sample rate,
+     *  assuming AudioTrack and AudioRecord share the same limitations.
+     * @hide
+     */
+    // never unhide
+    public static final int SAMPLE_RATE_HZ_MIN = 4000;
+    /** Maximum value for sample rate,
+     *  assuming AudioTrack and AudioRecord share the same limitations.
+     * @hide
+     */
+    // never unhide
+    public static final int SAMPLE_RATE_HZ_MAX = 192000;
+    /** Sample rate will be a route-dependent value.
+     * For AudioTrack, it is usually the sink sample rate,
+     * and for AudioRecord it is usually the source sample rate.
+     */
+    public static final int SAMPLE_RATE_UNSPECIFIED = 0;
+
     /**
      * @hide
      * Return the input channel mask corresponding to an output channel mask.
@@ -561,7 +579,7 @@
     }
 
     /**
-     * Constructor used by the JNI
+     * Constructor used by the JNI.  Parameters are not checked for validity.
      */
     // Update sound trigger JNI in core/jni/android_hardware_SoundTrigger.cpp when modifying this
     // constructor
@@ -610,12 +628,9 @@
     /**
      * Return the sample rate.
      * @return one of the values that can be set in {@link Builder#setSampleRate(int)} or
-     * 0 if not set.
+     * {@link #SAMPLE_RATE_UNSPECIFIED} if not set.
      */
     public int getSampleRate() {
-        if ((mPropertySetMask & AUDIO_FORMAT_HAS_PROPERTY_SAMPLE_RATE) == 0) {
-            return 0;
-        }
         return mSampleRate;
     }
 
@@ -687,7 +702,7 @@
      */
     public static class Builder {
         private int mEncoding = ENCODING_INVALID;
-        private int mSampleRate = 0;
+        private int mSampleRate = SAMPLE_RATE_UNSPECIFIED;
         private int mChannelMask = CHANNEL_INVALID;
         private int mChannelIndexMask = 0;
         private int mPropertySetMask = AUDIO_FORMAT_HAS_PROPERTY_NONE;
@@ -718,6 +733,8 @@
         public AudioFormat build() {
             AudioFormat af = new AudioFormat(1980/*ignored*/);
             af.mEncoding = mEncoding;
+            // not calling setSampleRate is equivalent to calling
+            // setSampleRate(SAMPLE_RATE_UNSPECIFIED)
             af.mSampleRate = mSampleRate;
             af.mChannelMask = mChannelMask;
             af.mChannelIndexMask = mChannelIndexMask;
@@ -795,7 +812,7 @@
          *    are specified but do not have the same channel count.
          */
         public @NonNull Builder setChannelMask(int channelMask) {
-            if (channelMask == 0) {
+            if (channelMask == CHANNEL_INVALID) {
                 throw new IllegalArgumentException("Invalid zero channel mask");
             } else if (/* channelMask != 0 && */ mChannelIndexMask != 0 &&
                     Integer.bitCount(channelMask) != Integer.bitCount(mChannelIndexMask)) {
@@ -867,7 +884,11 @@
          * @throws java.lang.IllegalArgumentException
          */
         public Builder setSampleRate(int sampleRate) throws IllegalArgumentException {
-            if ((sampleRate <= 0) || (sampleRate > 192000)) {
+            // TODO Consider whether to keep the MIN and MAX range checks here.
+            // It is not necessary and poses the problem of defining the limits independently from
+            // native implementation or platform capabilities.
+            if (((sampleRate < SAMPLE_RATE_HZ_MIN) || (sampleRate > SAMPLE_RATE_HZ_MAX)) &&
+                    sampleRate != SAMPLE_RATE_UNSPECIFIED) {
                 throw new IllegalArgumentException("Invalid sample rate " + sampleRate);
             }
             mSampleRate = sampleRate;
diff --git a/media/java/android/media/AudioManager.java b/media/java/android/media/AudioManager.java
index dc534be..38e3b15 100644
--- a/media/java/android/media/AudioManager.java
+++ b/media/java/android/media/AudioManager.java
@@ -3321,6 +3321,7 @@
      * Used as a key for {@link #getProperty} to request the native or optimal output sample rate
      * for this device's primary output stream, in decimal Hz.
      */
+    // FIXME Deprecate
     public static final String PROPERTY_OUTPUT_SAMPLE_RATE =
             "android.media.property.OUTPUT_SAMPLE_RATE";
 
@@ -3328,6 +3329,7 @@
      * Used as a key for {@link #getProperty} to request the native or optimal output buffer size
      * for this device's primary output stream, in decimal PCM frames.
      */
+    // FIXME Deprecate
     public static final String PROPERTY_OUTPUT_FRAMES_PER_BUFFER =
             "android.media.property.OUTPUT_FRAMES_PER_BUFFER";
 
diff --git a/media/java/android/media/AudioRecord.java b/media/java/android/media/AudioRecord.java
index e342385..8f6b178 100644
--- a/media/java/android/media/AudioRecord.java
+++ b/media/java/android/media/AudioRecord.java
@@ -57,10 +57,6 @@
     // Constants
     //--------------------
 
-    /** Minimum value for sample rate */
-    private static final int SAMPLE_RATE_HZ_MIN = 4000;
-    /** Maximum value for sample rate */
-    private static final int SAMPLE_RATE_HZ_MAX = 192000;
 
     /**
      *  indicates AudioRecord state is not successfully initialized.
@@ -168,8 +164,9 @@
     //--------------------
     /**
      * The audio data sampling rate in Hz.
+     * Never {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED}.
      */
-    private int mSampleRate;
+    private int mSampleRate; // initialized by all constructors via audioParamCheck()
     /**
      * The number of input audio channels (1 is mono, 2 is stereo)
      */
@@ -251,6 +248,9 @@
      * @param sampleRateInHz the sample rate expressed in Hertz. 44100Hz is currently the only
      *   rate that is guaranteed to work on all devices, but other rates such as 22050,
      *   16000, and 11025 may work on some devices.
+     *   {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED} means to use a route-dependent value
+     *   which is usually the sample rate of the source.
+     *   {@link #getSampleRate()} can be used to retrieve the actual sample rate chosen.
      * @param channelConfig describes the configuration of the audio channels.
      *   See {@link AudioFormat#CHANNEL_IN_MONO} and
      *   {@link AudioFormat#CHANNEL_IN_STEREO}.  {@link AudioFormat#CHANNEL_IN_MONO} is guaranteed
@@ -337,16 +337,9 @@
             mAudioAttributes = attributes;
         }
 
-        int rate = 0;
-        if ((format.getPropertySetMask()
-                & AudioFormat.AUDIO_FORMAT_HAS_PROPERTY_SAMPLE_RATE) != 0)
-        {
-            rate = format.getSampleRate();
-        } else {
-            rate = AudioSystem.getPrimaryOutputSamplingRate();
-            if (rate <= 0) {
-                rate = 44100;
-            }
+        int rate = format.getSampleRate();
+        if (rate == AudioFormat.SAMPLE_RATE_UNSPECIFIED) {
+            rate = 0;
         }
 
         int encoding = AudioFormat.ENCODING_DEFAULT;
@@ -373,12 +366,13 @@
 
         audioBuffSizeCheck(bufferSizeInBytes);
 
+        int[] sampleRate = new int[] {mSampleRate};
         int[] session = new int[1];
         session[0] = sessionId;
         //TODO: update native initialization when information about hardware init failure
         //      due to capture device already open is available.
         int initResult = native_setup( new WeakReference<AudioRecord>(this),
-                mAudioAttributes, mSampleRate, mChannelMask, mChannelIndexMask,
+                mAudioAttributes, sampleRate, mChannelMask, mChannelIndexMask,
                 mAudioFormat, mNativeBufferSizeInBytes,
                 session, ActivityThread.currentOpPackageName());
         if (initResult != SUCCESS) {
@@ -386,6 +380,7 @@
             return; // with mState == STATE_UNINITIALIZED
         }
 
+        mSampleRate = sampleRate[0];
         mSessionId = session[0];
 
         mState = STATE_INITIALIZED;
@@ -623,6 +618,7 @@
 
         return mask;
     }
+
     // postconditions:
     //    mRecordSource is valid
     //    mAudioFormat is valid
@@ -642,7 +638,9 @@
 
         //--------------
         // sample rate
-        if ((sampleRateInHz < SAMPLE_RATE_HZ_MIN) || (sampleRateInHz > SAMPLE_RATE_HZ_MAX)) {
+        if ((sampleRateInHz < AudioFormat.SAMPLE_RATE_HZ_MIN ||
+                sampleRateInHz > AudioFormat.SAMPLE_RATE_HZ_MAX) &&
+                sampleRateInHz != AudioFormat.SAMPLE_RATE_UNSPECIFIED) {
             throw new IllegalArgumentException(sampleRateInHz
                     + "Hz is not a supported sample rate.");
         }
@@ -714,7 +712,11 @@
     // Getters
     //--------------------
     /**
-     * Returns the configured audio data sample rate in Hz
+     * Returns the configured audio sink sample rate in Hz.
+     * The sink sample rate never changes after construction.
+     * If the constructor had a specific sample rate, then the sink sample rate is that value.
+     * If the constructor had {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED},
+     * then the sink sample rate is a route-dependent default value based on the source [sic].
      */
     public int getSampleRate() {
         return mSampleRate;
@@ -861,6 +863,7 @@
      * See {@link #AudioRecord(int, int, int, int, int)} for more information on valid
      * configuration values.
      * @param sampleRateInHz the sample rate expressed in Hertz.
+     *   {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED} is not permitted.
      * @param channelConfig describes the configuration of the audio channels.
      *   See {@link AudioFormat#CHANNEL_IN_MONO} and
      *   {@link AudioFormat#CHANNEL_IN_STEREO}
@@ -1708,7 +1711,7 @@
 
     private native final int native_setup(Object audiorecord_this,
             Object /*AudioAttributes*/ attributes,
-            int sampleRate, int channelMask, int channelIndexMask, int audioFormat,
+            int[] sampleRate, int channelMask, int channelIndexMask, int audioFormat,
             int buffSizeInBytes, int[] sessionId, String opPackageName);
 
     // TODO remove: implementation calls directly into implementation of native_release()
diff --git a/media/java/android/media/AudioTrack.java b/media/java/android/media/AudioTrack.java
index 6fc2f87..708768c 100644
--- a/media/java/android/media/AudioTrack.java
+++ b/media/java/android/media/AudioTrack.java
@@ -91,11 +91,6 @@
      */
     private static final float GAIN_MAX = 1.0f;
 
-    /** Minimum value for sample rate */
-    private static final int SAMPLE_RATE_HZ_MIN = 4000;
-    /** Maximum value for sample rate */
-    private static final int SAMPLE_RATE_HZ_MAX = 192000;
-
     /** Maximum value for AudioTrack channel count
      * @hide public for MediaCode only, do not un-hide or change to a numeric literal
      */
@@ -254,6 +249,7 @@
     private final Looper mInitializationLooper;
     /**
      * The audio data source sampling rate in Hz.
+     * Never {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED}.
      */
     private int mSampleRate; // initialized by all constructors via audioParamCheck()
     /**
@@ -340,6 +336,9 @@
      *   {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC},
      *   {@link AudioManager#STREAM_ALARM}, and {@link AudioManager#STREAM_NOTIFICATION}.
      * @param sampleRateInHz the initial source sample rate expressed in Hz.
+     *   {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED} means to use a route-dependent value
+     *   which is usually the sample rate of the sink.
+     *   {@link #getSampleRate()} can be used to retrieve the actual sample rate chosen.
      * @param channelConfig describes the configuration of the audio channels.
      *   See {@link AudioFormat#CHANNEL_OUT_MONO} and
      *   {@link AudioFormat#CHANNEL_OUT_STEREO}
@@ -389,6 +388,8 @@
      *   {@link AudioManager#STREAM_RING}, {@link AudioManager#STREAM_MUSIC},
      *   {@link AudioManager#STREAM_ALARM}, and {@link AudioManager#STREAM_NOTIFICATION}.
      * @param sampleRateInHz the initial source sample rate expressed in Hz.
+     *   {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED} means to use a route-dependent value
+     *   which is usually the sample rate of the sink.
      * @param channelConfig describes the configuration of the audio channels.
      *   See {@link AudioFormat#CHANNEL_OUT_MONO} and
      *   {@link AudioFormat#CHANNEL_OUT_STEREO}
@@ -461,16 +462,11 @@
             looper = Looper.getMainLooper();
         }
 
-        int rate = 0;
-        if ((format.getPropertySetMask() & AudioFormat.AUDIO_FORMAT_HAS_PROPERTY_SAMPLE_RATE) != 0)
-        {
-            rate = format.getSampleRate();
-        } else {
-            rate = AudioSystem.getPrimaryOutputSamplingRate();
-            if (rate <= 0) {
-                rate = 44100;
-            }
+        int rate = format.getSampleRate();
+        if (rate == AudioFormat.SAMPLE_RATE_UNSPECIFIED) {
+            rate = 0;
         }
+
         int channelIndexMask = 0;
         if ((format.getPropertySetMask()
                 & AudioFormat.AUDIO_FORMAT_HAS_PROPERTY_CHANNEL_INDEX_MASK) != 0) {
@@ -503,17 +499,19 @@
             throw new IllegalArgumentException("Invalid audio session ID: "+sessionId);
         }
 
+        int[] sampleRate = new int[] {mSampleRate};
         int[] session = new int[1];
         session[0] = sessionId;
         // native initialization
         int initResult = native_setup(new WeakReference<AudioTrack>(this), mAttributes,
-                mSampleRate, mChannelMask, mChannelIndexMask, mAudioFormat,
+                sampleRate, mChannelMask, mChannelIndexMask, mAudioFormat,
                 mNativeBufferSizeInBytes, mDataLoadMode, session);
         if (initResult != SUCCESS) {
             loge("Error code "+initResult+" when initializing AudioTrack.");
             return; // with mState == STATE_UNINITIALIZED
         }
 
+        mSampleRate = sampleRate[0];
         mSessionId = session[0];
 
         if (mDataLoadMode == MODE_STATIC) {
@@ -712,7 +710,7 @@
             if (mFormat == null) {
                 mFormat = new AudioFormat.Builder()
                         .setChannelMask(AudioFormat.CHANNEL_OUT_STEREO)
-                        .setSampleRate(AudioSystem.getPrimaryOutputSamplingRate())
+                        //.setSampleRate(AudioFormat.SAMPLE_RATE_UNSPECIFIED)
                         .setEncoding(AudioFormat.ENCODING_DEFAULT)
                         .build();
             }
@@ -762,7 +760,9 @@
                                  int audioFormat, int mode) {
         //--------------
         // sample rate, note these values are subject to change
-        if (sampleRateInHz < SAMPLE_RATE_HZ_MIN || sampleRateInHz > SAMPLE_RATE_HZ_MAX) {
+        if ((sampleRateInHz < AudioFormat.SAMPLE_RATE_HZ_MIN ||
+                sampleRateInHz > AudioFormat.SAMPLE_RATE_HZ_MAX) &&
+                sampleRateInHz != AudioFormat.SAMPLE_RATE_UNSPECIFIED) {
             throw new IllegalArgumentException(sampleRateInHz
                     + "Hz is not a supported sample rate.");
         }
@@ -948,7 +948,13 @@
     }
 
     /**
-     * Returns the configured audio data sample rate in Hz
+     * Returns the configured audio source sample rate in Hz.
+     * The initial source sample rate depends on the constructor parameters,
+     * but the source sample rate may change if {@link #setPlaybackRate(int)} is called.
+     * If the constructor had a specific sample rate, then the initial sink sample rate is that
+     * value.
+     * If the constructor had {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED},
+     * then the initial sink sample rate is a route-dependent default value based on the source [sic].
      */
     public int getSampleRate() {
         return mSampleRate;
@@ -1218,6 +1224,7 @@
      * to a higher value than the initial source sample rate, be sure to configure the buffer size
      * based on the highest planned sample rate.
      * @param sampleRateInHz the source sample rate expressed in Hz.
+     *   {@link AudioFormat#SAMPLE_RATE_UNSPECIFIED} is not permitted.
      * @param channelConfig describes the configuration of the audio channels.
      *   See {@link AudioFormat#CHANNEL_OUT_MONO} and
      *   {@link AudioFormat#CHANNEL_OUT_STEREO}
@@ -1255,7 +1262,9 @@
         }
 
         // sample rate, note these values are subject to change
-        if ( (sampleRateInHz < SAMPLE_RATE_HZ_MIN) || (sampleRateInHz > SAMPLE_RATE_HZ_MAX) ) {
+        // Note: AudioFormat.SAMPLE_RATE_UNSPECIFIED is not allowed
+        if ( (sampleRateInHz < AudioFormat.SAMPLE_RATE_HZ_MIN) ||
+                (sampleRateInHz > AudioFormat.SAMPLE_RATE_HZ_MAX) ) {
             loge("getMinBufferSize(): " + sampleRateInHz + " Hz is not a supported sample rate.");
             return ERROR_BAD_VALUE;
         }
@@ -2763,7 +2772,7 @@
     //     AudioAttributes.USAGE_MEDIA will map to AudioManager.STREAM_MUSIC
     private native final int native_setup(Object /*WeakReference<AudioTrack>*/ audiotrack_this,
             Object /*AudioAttributes*/ attributes,
-            int sampleRate, int channelMask, int channelIndexMask, int audioFormat,
+            int[] sampleRate, int channelMask, int channelIndexMask, int audioFormat,
             int buffSizeInBytes, int mode, int[] sessionId);
 
     private native final void native_finalize();
diff --git a/media/java/android/media/audiopolicy/AudioMix.java b/media/java/android/media/audiopolicy/AudioMix.java
index 4ffac6d..55fb82b 100644
--- a/media/java/android/media/audiopolicy/AudioMix.java
+++ b/media/java/android/media/audiopolicy/AudioMix.java
@@ -277,6 +277,7 @@
                 mRouteFlags = ROUTE_FLAG_RENDER;
             }
             if (mFormat == null) {
+                // FIXME Can we eliminate this?  Will AudioMix work with an unspecified sample rate?
                 int rate = AudioSystem.getPrimaryOutputSamplingRate();
                 if (rate <= 0) {
                     rate = 44100;