Fixed region cloning per #26

Author: davidgyoung

src/main/java/org/altbeacon/beacon/Region.java

@@ -208,10 +208,12 @@ protected Region(Region otherRegion) {
         super();
         mIdentifiers = new ArrayList<Identifier>(otherRegion.mIdentifiers.size());
         for (int i = 0; i < otherRegion.mIdentifiers.size(); i++) {
-            mIdentifiers.add(new Identifier(otherRegion.mIdentifiers.get(i)));
+            Identifier otherIdentifier = otherRegion.mIdentifiers.get(i);
+            mIdentifiers.add(otherIdentifier != null ? new Identifier(otherIdentifier) : null);
         }
         mUniqueId = otherRegion.mUniqueId;
     }
+    
     protected Region() {
     }
 

src/test/java/org/altbeacon/beacon/RegionTest.java

@@ -82,6 +82,15 @@ public void testToString() {
         assertEquals("id1: 1 id2: 2 id3: null", region.toString());
     }
 
+    @Test
+    public void testCopyConstructor() {
+        Region region = new Region("myRegion", Identifier.parse("1"), Identifier.parse("2"), null);
+        Region region2 = new Region(region);
+        assertEquals(region, region2);
+        assertNull(region2.getId3());
+    }
+
+
     @Test
     public void testConvenienceIdentifierAccessors() {
         Region region = new Region("myRegion", Identifier.parse("1"), Identifier.parse("2"), Identifier.parse("3"));