Merge "Add Bytes.java"
diff --git a/nearby/service/Android.bp b/nearby/service/Android.bp
index 4982d1f..b33d593 100644
--- a/nearby/service/Android.bp
+++ b/nearby/service/Android.bp
@@ -60,4 +60,4 @@
apex_available: [
"com.android.nearby",
],
-}
\ No newline at end of file
+}
diff --git a/nearby/service/java/com/android/server/nearby/common/bluetooth/fastpair/Bytes.java b/nearby/service/java/com/android/server/nearby/common/bluetooth/fastpair/Bytes.java
new file mode 100644
index 0000000..637cd03
--- /dev/null
+++ b/nearby/service/java/com/android/server/nearby/common/bluetooth/fastpair/Bytes.java
@@ -0,0 +1,118 @@
+/*
+ * Copyright 2021 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.server.nearby.common.bluetooth.fastpair;
+
+import androidx.annotation.Nullable;
+
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.ShortBuffer;
+import java.util.Arrays;
+
+/** Represents a block of bytes, with hashCode and equals. */
+public abstract class Bytes {
+ private static final char[] sHexDigits = "0123456789abcdef".toCharArray();
+ private final byte[] mBytes;
+
+ /**
+ * A logical value consisting of one or more bytes in the given order (little-endian, i.e.
+ * LSO...MSO, or big-endian, i.e. MSO...LSO). E.g. the Fast Pair Model ID is a 3-byte value,
+ * and a Bluetooth device address is a 6-byte value.
+ */
+ public static class Value extends Bytes {
+ private final ByteOrder mByteOrder;
+
+ /**
+ * Constructor.
+ */
+ public Value(byte[] bytes, ByteOrder byteOrder) {
+ super(bytes);
+ this.mByteOrder = byteOrder;
+ }
+
+ /**
+ * Gets bytes.
+ */
+ public byte[] getBytes(ByteOrder byteOrder) {
+ return this.mByteOrder.equals(byteOrder) ? getBytes() : reverse(getBytes());
+ }
+
+ private static byte[] reverse(byte[] bytes) {
+ byte[] reversedBytes = new byte[bytes.length];
+ for (int i = 0; i < bytes.length; i++) {
+ reversedBytes[i] = bytes[bytes.length - i - 1];
+ }
+ return reversedBytes;
+ }
+ }
+
+ Bytes(byte[] bytes) {
+ mBytes = bytes;
+ }
+
+ private static String toHexString(byte[] bytes) {
+ StringBuilder sb = new StringBuilder(2 * bytes.length);
+ for (byte b : bytes) {
+ sb.append(sHexDigits[(b >> 4) & 0xf]).append(sHexDigits[b & 0xf]);
+ }
+ return sb.toString();
+ }
+
+ /** Returns 2-byte values in the same order, each using the given byte order. */
+ public static byte[] toBytes(ByteOrder byteOrder, short... shorts) {
+ ByteBuffer byteBuffer = ByteBuffer.allocate(shorts.length * 2).order(byteOrder);
+ for (short s : shorts) {
+ byteBuffer.putShort(s);
+ }
+ return byteBuffer.array();
+ }
+
+ /** Returns the shorts in the same order, each converted using the given byte order. */
+ static short[] toShorts(ByteOrder byteOrder, byte[] bytes) {
+ ShortBuffer shortBuffer = ByteBuffer.wrap(bytes).order(byteOrder).asShortBuffer();
+ short[] shorts = new short[shortBuffer.remaining()];
+ shortBuffer.get(shorts);
+ return shorts;
+ }
+
+ /** @return The bytes. */
+ public byte[] getBytes() {
+ return mBytes;
+ }
+
+ @Override
+ public boolean equals(@Nullable Object o) {
+ if (this == o) {
+ return true;
+ }
+ if (!(o instanceof Bytes)) {
+ return false;
+ }
+ Bytes that = (Bytes) o;
+ return Arrays.equals(mBytes, that.mBytes);
+ }
+
+ @Override
+ public int hashCode() {
+ return Arrays.hashCode(mBytes);
+ }
+
+ @Override
+ public String toString() {
+ return toHexString(mBytes);
+ }
+}