diff --git a/Zutil.iml b/Zutil.iml
index 789635f..28d731d 100644
--- a/Zutil.iml
+++ b/Zutil.iml
@@ -6,7 +6,7 @@
       <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
       <sourceFolder url="file://$MODULE_DIR$/test" isTestSource="true" />
     </content>
-    <orderEntry type="inheritedJdk" />
+    <orderEntry type="jdk" jdkName="1.8" jdkType="JavaSDK" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="module-library" scope="TEST">
       <library name="JUnit4">
diff --git a/src/zutil/parser/json/JSONObjectInputStream.java b/src/zutil/parser/json/JSONObjectInputStream.java
old mode 100644
new mode 100755
index 1f49358..2070c9e
--- a/src/zutil/parser/json/JSONObjectInputStream.java
+++ b/src/zutil/parser/json/JSONObjectInputStream.java
@@ -130,6 +130,8 @@ public class JSONObjectInputStream extends InputStream implements ObjectInput, C
 
     @SuppressWarnings({ "rawtypes", "unchecked" })
     protected Object readType(Class<?> type, Class<?>[] genType, String key, DataNode json) throws IllegalAccessException, ClassNotFoundException, InstantiationException, UnsupportedDataTypeException, NoSuchFieldException {
+        if(json == null)
+            return null;
         // Field type is a primitive?
         if(type.isPrimitive() || String.class.isAssignableFrom(type)){
             return readPrimitive(type, json);
@@ -171,7 +173,7 @@ public class JSONObjectInputStream extends InputStream implements ObjectInput, C
 
     protected Object readObject(Class<?> type, String key, DataNode json) throws IllegalAccessException, InstantiationException, ClassNotFoundException, IllegalArgumentException, UnsupportedDataTypeException, NoSuchFieldException {
         // Only parse if json is a map
-        if(!json.isMap())
+        if(json == null || !json.isMap())
             return null;
         // See if the Object id is in the cache before continuing
         if(json.getString("@object_id") != null && objectCache.containsKey(json.getInt(MD_OBJECT_ID)))
diff --git a/test/zutil/test/JSONSerializerTest.java b/test/zutil/test/JSONSerializerTest.java
index c692f36..802f4ca 100755
--- a/test/zutil/test/JSONSerializerTest.java
+++ b/test/zutil/test/JSONSerializerTest.java
@@ -48,7 +48,7 @@ public class JSONSerializerTest{
         data = data.replace("\"", "'");
 
         assertEquals(
-                "{'str': 'abcd', '@class': 'zutil.test.JSONSerializerTest$TestClass', 'obj2': {'@class': 'zutil.test.JSONSerializerTest$TestObj', '@object_id': 3, 'value': 42}, '@object_id': 1, 'obj1': {'@class': 'zutil.test.JSONSerializerTest$TestObj', '@object_id': 2, 'value': 42}, 'decimal': 1.1}\n",
+                "{'str': 'abcd', '@class': 'zutil.test.JSONSerializerTest$TestClass', 'obj1': {'@class': 'zutil.test.JSONSerializerTest$TestObj', 'value': 42, '@object_id': 2}, 'obj2': {'@class': 'zutil.test.JSONSerializerTest$TestObj', 'value': 42, '@object_id': 3}, 'decimal': 1.1, '@object_id': 1}\n",
                 data);
     }
 	
@@ -69,7 +69,7 @@ public class JSONSerializerTest{
         data = data.replace("\"", "'");
 
         assertEquals(
-                "{'@class': 'zutil.test.JSONSerializerTest$TestClassObjClone', 'obj2': {'@object_id': 2}, '@object_id': 1, 'obj1': {'@class': 'zutil.test.JSONSerializerTest$TestObj', '@object_id': 2, 'value': 42}}\n",
+                "{'@class': 'zutil.test.JSONSerializerTest$TestClassObjClone', 'obj1': {'@class': 'zutil.test.JSONSerializerTest$TestObj', 'value': 42, '@object_id': 2}, 'obj2': {'@object_id': 2}, '@object_id': 1}\n",
                 data);
     }
 	
@@ -113,7 +113,7 @@ public class JSONSerializerTest{
     }
 
 	@Test
-	public void testSerializerWithNullFields() throws InterruptedException, IOException, ClassNotFoundException{
+	public void testSerializerWithNullFieldsHidden() throws InterruptedException, IOException, ClassNotFoundException{
 		TestClass sourceObj = new TestClass();
 
 		String data = writeObjectToJson(sourceObj, false);
@@ -133,13 +133,28 @@ public class JSONSerializerTest{
 		String data = writeObjectToJson(sourceObj, false);
 		data = data.replace("\"", "'");
 		assertEquals(
-				"{'map': {'key1': 'value1', 'key2': 'value2'}}\n",
+				"{'map': {'key2': 'value2', 'key1': 'value1'}}\n",
 				data);
 
         TestClassMap targetObj = sendReceiveObject(sourceObj);
         TestClassMap.assertEquals(sourceObj, targetObj);
 	}
 
+    @Test
+    public void testSerializerWithMapFieldWithNullEntry() throws InterruptedException, IOException, ClassNotFoundException{
+        TestClassMap sourceObj = new TestClassMap().init();
+        sourceObj.map.put("key1", null);
+
+        String data = writeObjectToJson(sourceObj, false);
+        data = data.replace("\"", "'");
+        assertEquals(
+                "{'map': {'key2': 'value2', 'key1': null}}\n",
+                data);
+
+        TestClassMap targetObj = sendReceiveObject(sourceObj);
+        TestClassMap.assertEquals(sourceObj, targetObj);
+    }
+
     @Test
     public void testSerializerWithListField() throws InterruptedException, IOException, ClassNotFoundException{
         TestClassList sourceObj = new TestClassList().init();