Renamed datagrid and datastore packages

net.onrc.onos.datagrid.* => net.onrc.onos.core.datagrid.*
net.onrc.onos.datastore.* => net.onrc.onos.core.datastore.*

Change-Id: Ibe1894a6fabae08ea7cfcbf6595f0c91b05ef497
diff --git a/src/main/java/net/onrc/onos/core/datastore/utils/ByteArrayComparator.java b/src/main/java/net/onrc/onos/core/datastore/utils/ByteArrayComparator.java
new file mode 100644
index 0000000..f937e50
--- /dev/null
+++ b/src/main/java/net/onrc/onos/core/datastore/utils/ByteArrayComparator.java
@@ -0,0 +1,24 @@
+package net.onrc.onos.core.datastore.utils;
+
+import java.nio.ByteBuffer;
+import java.util.Comparator;
+
+/**
+ * Comparator which will compares the content of byte[].
+ *
+ * Expected to be used with TreeMap, etc. when you want to use byte[] as a key.
+ */
+public final class ByteArrayComparator implements Comparator<byte[]> {
+
+    /**
+     * Instance which can be used, if you want to avoid instantiation per Map.
+     */
+    public static final ByteArrayComparator BYTEARRAY_COMPARATOR = new ByteArrayComparator();
+
+    @Override
+    public int compare(final byte[] o1, final byte[] o2) {
+        final ByteBuffer b1 = ByteBuffer.wrap(o1);
+        final ByteBuffer b2 = ByteBuffer.wrap(o2);
+        return b1.compareTo(b2);
+    }
+}