Merge "Sensor: Make getId() more varied" into nyc-dev (94b61cb3) · Commits · e / os / android_frameworks_base

core/java/android/hardware/Sensor.java

+21 −40

Original line number	Diff line number	Diff line
		@@ -20,8 +20,6 @@ package android.hardware;
		import android.annotation.SystemApi;
		import android.os.Build;

		import java.util.UUID;

		/**
		* Class representing a sensor. Use {@link SensorManager#getSensorList} to get
		* the list of available Sensors.
		@@ -806,7 +804,7 @@ public final class Sensor {
		private String mRequiredPermission;
		private int mMaxDelay;
		private int mFlags;
		private UUID mUuid;
		private int mId;

		Sensor() {
		}
		@@ -895,34 +893,28 @@ public final class Sensor {
		}

		/**
		* @return The UUID of the sensor. If the sensor does not support UUID, the returned value will
		* be an all zero UUID; if the sensor's combination of type and name is guaranteed to be unique
		* in system, the return value will be an all "F" UUID.
		* Do not use.
		*
		* This method throws an UnsupportedOperationException.
		*
		* Use getId() if you want a unique ID.
		*
		* @see getId
		*
		* @hide
		*/
		@SystemApi
		public UUID getUuid() {
		return mUuid;
		public java.util.UUID getUuid() {
		throw new UnsupportedOperationException();
		}

		/**
		* @return The unique id of sensor. Return value of 0 means this sensor does not support UUID;
		* return value of -1 means this sensor can be uniquely identified in system by combination of
		* its type and name.
		* @return The sensor id that will be unique for the same app unless the device is factory
		* reset. Return value of 0 means this sensor does not support this function; return value of -1
		* means this sensor can be uniquely identified in system by combination of its type and name.
		*/
		public int getId() {
		if (mUuid.equals(ALL_0_UUID)) {
		return 0;
		} else if (mUuid.equals(ALL_F_UUID)) {
		return -1;
		} else {
		int id = Math.abs(mUuid.hashCode()) + 1;
		if (id <= 0) { // catch corner case when hash is Integer.MIN_VALUE and Integer.MAX_VALUE
		id = 1;
		}
		return id;
		}
		return mId;
		}

		/**
		@@ -1038,10 +1030,6 @@ public final class Sensor {
		+ ", power=" + mPower + ", minDelay=" + mMinDelay + "}";
		}

		//special UUID hash constant
		private final static UUID ALL_0_UUID = new UUID(0,0);
		private final static UUID ALL_F_UUID = new UUID(~0L, ~0L);

		/**
		* Sets the Type associated with the sensor.
		* NOTE: to be used only by native bindings in SensorManager.
		@@ -1141,24 +1129,17 @@ public final class Sensor {
		}

		/**
		* Sets the UUID associated with the sensor.
		* Sets the ID associated with the sensor.
		*
		* The method name is misleading; while this ID is based on the UUID,
		* we do not pass in the actual UUID.
		*
		* NOTE: to be used only by native bindings in SensorManager.
		*
		* @see #getUuid
		* @see UUID
		* @see #getId
		*/
		private void setUuid(long msb, long lsb) {
		// reuse static object if possible
		if (msb == lsb) {
		if (msb == 0L) {
		mUuid = ALL_0_UUID;
		return;
		} else if (msb == ~0L) {
		mUuid = ALL_F_UUID;
		return;
		}
		}
		mUuid = new UUID(msb, lsb);
		// TODO(b/29547335): Rename this method to setId.
		mId = (int)msb;
		}
		}

core/jni/android_hardware_SensorManager.cpp

+3 −14

Original line number	Diff line number	Diff line
		@@ -30,7 +30,6 @@
		#include <utils/Looper.h>
		#include <utils/Vector.h>

		#include <endian.h> // htobe64
		#include <map>

		namespace {
		@@ -200,19 +199,9 @@ translateNativeSensorToJavaSensor(JNIEnv *env, jobject sensor, const Sensor& nat
		env->SetObjectField(sensor, sensorOffsets.stringType, stringType);
		}

		// java.util.UUID constructor UUID(long a, long b) assumes the two long inputs a and b
		// correspond to first half and second half of the 16-byte stream in big-endian,
		// respectively, if the byte stream is serialized according to RFC 4122 (Sec. 4.1.2).
		//
		// For Java UUID 12345678-90AB-CDEF-1122-334455667788, the byte stream will be
		// (uint8_t) {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF, ....} according RFC 4122.
		//
		// According to Java UUID constructor document, the long parameter a should be always
		// 0x12345678980ABCDEF regardless of host machine endianess. Thus, htobe64 is used to
		// convert int64_t read directly, which will be in host-endian, to the big-endian required
		// by Java constructor.
		const int64_t (&uuid)[2] = nativeSensor.getUuid().i64;
		env->CallVoidMethod(sensor, sensorOffsets.setUuid, htobe64(uuid[0]), htobe64(uuid[1]));
		// TODO(b/29547335): Rename "setUuid" method to "setId".
		int64_t id = nativeSensor.getId();
		env->CallVoidMethod(sensor, sensorOffsets.setUuid, id, 0);
		}
		return sensor;
		}