Add LinkAddress

LinkAddress stores IP address + prefix for a network link

Change-Id: Id3e74e9d0a62121d097ebdc9be064eeea257ba1f

1 files changed, 149 insertions, 0 deletions

diff --git a/core/java/android/net/LinkAddress.java b/core/java/android/net/LinkAddress.java
new file mode 100644
index 000000000000..cb302da56b8f
--- /dev/null
+++ b/core/java/android/net/LinkAddress.java
@@ -0,0 +1,149 @@
+/*
+ * Copyright (C) 2010 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 android.os.Parcel;
+import android.os.Parcelable;
+
+import java.net.InetAddress;
+import java.net.InterfaceAddress;
+import java.net.UnknownHostException;
+
+/**
+ * Identifies an address of a network link
+ * @hide
+ */
+public class LinkAddress implements Parcelable {
+    /**
+     * IPv4 or IPv6 address.
+     */
+    private final InetAddress address;
+
+    /**
+     * Network prefix
+     */
+    private final int prefix;
+
+    public LinkAddress(InetAddress address, InetAddress mask) {
+        this.address = address;
+        this.prefix = computeprefix(mask);
+    }
+
+    public LinkAddress(InetAddress address, int prefix) {
+        this.address = address;
+        this.prefix = prefix;
+    }
+
+    public LinkAddress(InterfaceAddress interfaceAddress) {
+        this.address = interfaceAddress.getAddress();
+        this.prefix = interfaceAddress.getNetworkPrefixLength();
+    }
+
+    private static int computeprefix(InetAddress mask) {
+        int count = 0;
+        for (byte b : mask.getAddress()) {
+            for (int i = 0; i < 8; ++i) {
+                if ((b & (1 << i)) != 0) {
+                    ++count;
+                }
+            }
+        }
+        return count;
+    }
+
+    @Override
+    public String toString() {
+        return (address == null ? "" : (address.getHostAddress() + "/" + prefix));
+    }
+
+    /**
+     * Compares this {@code LinkAddress} instance against the specified address
+     * in {@code obj}. Two addresses are equal if their InetAddress and prefix
+     * are equal
+     *
+     * @param obj the object to be tested for equality.
+     * @return {@code true} if both objects are equal, {@code false} otherwise.
+     */
+    @Override
+    public boolean equals(Object obj) {
+        if (!(obj instanceof LinkAddress)) {
+            return false;
+        }
+        LinkAddress linkAddress = (LinkAddress) obj;
+        return this.address.equals(linkAddress.address) &&
+            this.prefix == linkAddress.prefix;
+    }
+
+    /**
+     * Returns the InetAddress for this address.
+     */
+    public InetAddress getAddress() {
+        return address;
+    }
+
+    /**
+     * Get network prefix length
+     */
+    public int getNetworkPrefix() {
+        return prefix;
+    }
+
+    /**
+     * Implement the Parcelable interface
+     * @hide
+     */
+    public int describeContents() {
+        return 0;
+    }
+
+    /**
+     * Implement the Parcelable interface.
+     * @hide
+     */
+    public void writeToParcel(Parcel dest, int flags) {
+        if (address != null) {
+            dest.writeByte((byte)1);
+            dest.writeByteArray(address.getAddress());
+            dest.writeInt(prefix);
+        } else {
+            dest.writeByte((byte)0);
+        }
+    }
+
+    /**
+     * Implement the Parcelable interface.
+     * @hide
+     */
+    public static final Creator<LinkAddress> CREATOR =
+        new Creator<LinkAddress>() {
+            public LinkAddress createFromParcel(Parcel in) {
+                InetAddress address = null;
+                int prefix = 0;
+                if (in.readByte() == 1) {
+                    try {
+                        address = InetAddress.getByAddress(in.createByteArray());
+                        prefix = in.readInt();
+                    } catch (UnknownHostException e) { }
+                }
+                return new LinkAddress(address, prefix);
+            }
+
+            public LinkAddress[] newArray(int size) {
+                return new LinkAddress[size];
+            }
+        };
+}