Merge "Define MacAddress class" am: 925349ac8f am: 37caaaa705

am: 491a93b5ac

Change-Id: I0e09e64bb2a6306c0422443038351fabf10e2d6e

core/java/android/net/MacAddress.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2017 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 android.net;
+
+import com.android.internal.annotations.VisibleForTesting;
+
+import java.util.Arrays;
+
+/**
+ * @hide
+ */
+public final class MacAddress {
+
+    // TODO: add isLocallyAssigned().
+    // TODO: add getRandomAddress() factory method.
+
+    private static final int ETHER_ADDR_LEN = 6;
+    private static final byte FF = (byte) 0xff;
+    @VisibleForTesting
+    static final byte[] ETHER_ADDR_BROADCAST = { FF, FF, FF, FF, FF, FF };
+
+    public enum MacAddressType {
+        UNICAST,
+        MULTICAST,
+        BROADCAST;
+    }
+
+    /** Return true if the given byte array is not null and has the length of a mac address. */
+    public static boolean isMacAddress(byte[] addr) {
+        return addr != null && addr.length == ETHER_ADDR_LEN;
+    }
+
+    /**
+     * Return the MacAddressType of the mac address represented by the given byte array,
+     * or null if the given byte array does not represent an mac address. */
+    public static MacAddressType macAddressType(byte[] addr) {
+        if (!isMacAddress(addr)) {
+            return null;
+        }
+        if (Arrays.equals(addr, ETHER_ADDR_BROADCAST)) {
+            return MacAddressType.BROADCAST;
+        }
+        if ((addr[0] & 0x01) == 1) {
+            return MacAddressType.MULTICAST;
+        }
+        return MacAddressType.UNICAST;
+    }
+}

tests/net/java/android/net/MacAddressTest.java

@@ -0,0 +1,77 @@
+/*
+ * Copyright 2017 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 android.net;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertFalse;
+
+import android.net.MacAddress.MacAddressType;
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+
+import java.util.Arrays;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+@SmallTest
+@RunWith(AndroidJUnit4.class)
+public class MacAddressTest {
+
+    static class AddrTypeTestCase {
+        byte[] addr;
+        MacAddressType expected;
+
+        static AddrTypeTestCase of(MacAddressType expected, int... addr) {
+            AddrTypeTestCase t = new AddrTypeTestCase();
+            t.expected = expected;
+            t.addr = toByteArray(addr);
+            return t;
+        }
+    }
+
+    @Test
+    public void testMacAddrTypes() {
+        AddrTypeTestCase[] testcases = {
+            AddrTypeTestCase.of(null),
+            AddrTypeTestCase.of(null, 0),
+            AddrTypeTestCase.of(null, 1, 2, 3, 4, 5),
+            AddrTypeTestCase.of(null, 1, 2, 3, 4, 5, 6, 7),
+            AddrTypeTestCase.of(MacAddressType.UNICAST, 0xa0, 0xb0, 0xc0, 0xd0, 0xe0, 0xf0),
+            AddrTypeTestCase.of(MacAddressType.BROADCAST, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff),
+            AddrTypeTestCase.of(MacAddressType.MULTICAST, 1, 2, 3, 4, 5, 6),
+            AddrTypeTestCase.of(MacAddressType.MULTICAST, 11, 22, 33, 44, 55, 66),
+            AddrTypeTestCase.of(MacAddressType.MULTICAST, 33, 33, 0xaa, 0xbb, 0xcc, 0xdd)
+        };
+
+        for (AddrTypeTestCase t : testcases) {
+            MacAddressType got = MacAddress.macAddressType(t.addr);
+            String msg = String.format("expected type of %s to be %s, but got %s",
+                    Arrays.toString(t.addr), t.expected, got);
+            assertEquals(msg, t.expected, got);
+        }
+    }
+
+    static byte[] toByteArray(int[] in) {
+        byte[] out = new byte[in.length];
+        for (int i = 0; i < in.length; i++) {
+            out[i] = (byte) in[i];
+        }
+        return out;
+    }
+}