diff --git a/app/src/androidTest/java/com/os/operando/garum/sample/ApplicationTest.java b/app/src/androidTest/java/com/os/operando/garum/sample/ApplicationTest.java
deleted file mode 100755
index 0ef4a5a..0000000
--- a/app/src/androidTest/java/com/os/operando/garum/sample/ApplicationTest.java
+++ /dev/null
@@ -1,13 +0,0 @@
-package com.os.operando.garum.sample;
-
-import android.app.Application;
-import android.test.ApplicationTestCase;
-
-/**
- * <a href="http://d.android.com/tools/testing/testing_android.html">Testing Fundamentals</a>
- */
-public class ApplicationTest extends ApplicationTestCase<Application> {
-    public ApplicationTest() {
-        super(Application.class);
-    }
-}
\ No newline at end of file
diff --git a/garum/build.gradle b/garum/build.gradle
index 083bac2..e77bcca 100644
--- a/garum/build.gradle
+++ b/garum/build.gradle
@@ -27,4 +27,7 @@ dependencies {
     compile fileTree(dir: 'libs', include: ['*.jar'])
 
     androidTestCompile('junit:junit:4.11')
+    androidTestCompile 'com.android.support.test:runner:0.5'
+    // Set this dependency to use JUnit 4 rules
+    androidTestCompile 'com.android.support.test:rules:0.5'
 }
diff --git a/garum/src/androidTest/java/com/os/operando/garum/ApplicationTest.java b/garum/src/androidTest/java/com/os/operando/garum/ApplicationTest.java
deleted file mode 100755
index 3e91397..0000000
--- a/garum/src/androidTest/java/com/os/operando/garum/ApplicationTest.java
+++ /dev/null
@@ -1,13 +0,0 @@
-package com.os.operando.garum;
-
-import android.app.Application;
-import android.test.ApplicationTestCase;
-
-/**
- * <a href="http://d.android.com/tools/testing/testing_android.html">Testing Fundamentals</a>
- */
-public class ApplicationTest extends ApplicationTestCase<Application> {
-    public ApplicationTest() {
-        super(Application.class);
-    }
-}
\ No newline at end of file
diff --git a/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest1.java b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest1.java
new file mode 100644
index 0000000..20f5406
--- /dev/null
+++ b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest1.java
@@ -0,0 +1,186 @@
+package com.os.operando.garum.models;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.support.test.runner.AndroidJUnit4;
+import android.test.ApplicationTestCase;
+
+import com.os.operando.garum.Garum;
+import com.os.operando.garum.annotations.Pref;
+import com.os.operando.garum.annotations.PrefKey;
+
+import junit.framework.Assert;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+// Basic PrefModel test.
+@RunWith(AndroidJUnit4.class)
+public class PrefModelTest1 extends ApplicationTestCase<Application> {
+
+    public PrefModelTest1() {
+        super(Application.class);
+    }
+
+    @Before
+    public void setUp() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+
+        Garum.initialize(getContext());
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+    }
+
+    // Test of raw preferences.
+    @Test
+    public void test1() {
+        Model model = new Model();
+        boolean result = model.save();
+        Assert.assertTrue(result); // Check save
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertFalse(prefs.contains("stringValue")); // String value isn't exist if it's null.
+        Assert.assertTrue(prefs.contains("intValue"));
+        Assert.assertTrue(prefs.contains("floatValue"));
+        Assert.assertTrue(prefs.contains("longValue"));
+        Assert.assertTrue(prefs.contains("booleanValue"));
+    }
+
+    // Test of #save method.
+    @Test
+    public void test2() {
+        Model model = new Model();
+        model.stringValue = "keep it simple stupid.";
+        model.intValue = 34565;
+        model.floatValue = 543.22f;
+        model.longValue = 123432L;
+        model.booleanValue = true;
+        boolean result = model.save();
+        Assert.assertTrue(result); // Check save
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("stringValue"));
+        Assert.assertTrue(prefs.contains("intValue"));
+        Assert.assertTrue(prefs.contains("floatValue"));
+        Assert.assertTrue(prefs.contains("longValue"));
+        Assert.assertTrue(prefs.contains("booleanValue"));
+
+        Assert.assertEquals("keep it simple stupid.", prefs.getString("stringValue", "DEFAULT"));
+        Assert.assertEquals(34565, prefs.getInt("intValue", 6503));
+        Assert.assertEquals(543.22f, prefs.getFloat("floatValue", 204.3f));
+        Assert.assertEquals(123432L, prefs.getLong("longValue", 3407L));
+        Assert.assertEquals(true, prefs.getBoolean("booleanValue", false));
+    }
+
+    // Test of #apply method.
+    @Test
+    public void test3() {
+        Model model = new Model();
+        model.stringValue = "keep it simple stupid.";
+        model.intValue = 34565;
+        model.floatValue = 543.22f;
+        model.longValue = 123432L;
+        model.booleanValue = true;
+        model.apply();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("stringValue"));
+        Assert.assertTrue(prefs.contains("intValue"));
+        Assert.assertTrue(prefs.contains("floatValue"));
+        Assert.assertTrue(prefs.contains("longValue"));
+        Assert.assertTrue(prefs.contains("booleanValue"));
+
+        Assert.assertEquals("keep it simple stupid.", prefs.getString("stringValue", "DEFAULT"));
+        Assert.assertEquals(34565, prefs.getInt("intValue", 6503));
+        Assert.assertEquals(543.22f, prefs.getFloat("floatValue", 204.3f));
+        Assert.assertEquals(123432L, prefs.getLong("longValue", 3407L));
+        Assert.assertEquals(true, prefs.getBoolean("booleanValue", false));
+    }
+
+    // Test of load.
+    @Test
+    public void test4() {
+        Model model = new Model();
+        model.stringValue = "keep it simple stupid.";
+        model.intValue = 34565;
+        model.floatValue = 543.22f;
+        model.longValue = 123432L;
+        model.booleanValue = true;
+        model.save();
+
+        // Load data
+        model = new Model();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("stringValue"));
+        Assert.assertTrue(prefs.contains("intValue"));
+        Assert.assertTrue(prefs.contains("floatValue"));
+        Assert.assertTrue(prefs.contains("longValue"));
+        Assert.assertTrue(prefs.contains("booleanValue"));
+
+        Assert.assertEquals("keep it simple stupid.", prefs.getString("stringValue", "DEFAULT"));
+        Assert.assertEquals(34565, prefs.getInt("intValue", 6503));
+        Assert.assertEquals(543.22f, prefs.getFloat("floatValue", 204.3f));
+        Assert.assertEquals(123432L, prefs.getLong("longValue", 3407L));
+        Assert.assertEquals(true, prefs.getBoolean("booleanValue", false));
+
+        Assert.assertEquals("keep it simple stupid.", model.stringValue);
+        Assert.assertEquals(34565, model.intValue);
+        Assert.assertEquals(543.22f, model.floatValue);
+        Assert.assertEquals(123432L, model.longValue);
+        Assert.assertEquals(true, model.booleanValue);
+    }
+
+    // Test of #clear method.
+    @Test
+    public void test5() {
+        Model model = new Model();
+        model.stringValue = "keep it simple stupid.";
+        model.intValue = 34565;
+        model.floatValue = 543.22f;
+        model.longValue = 123432L;
+        model.booleanValue = true;
+        model.save();
+
+        model.clear();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertFalse(prefs.contains("stringValue"));
+        Assert.assertFalse(prefs.contains("intValue"));
+        Assert.assertFalse(prefs.contains("floatValue"));
+        Assert.assertFalse(prefs.contains("longValue"));
+        Assert.assertFalse(prefs.contains("booleanValue"));
+
+        Assert.assertNull(model.stringValue);
+        Assert.assertEquals(0, model.intValue);
+        Assert.assertEquals(0f, model.floatValue);
+        Assert.assertEquals(0L, model.longValue);
+        Assert.assertEquals(false, model.booleanValue);
+    }
+
+    @Pref(name = "model")
+    public static class Model extends PrefModel {
+        @PrefKey
+        public String stringValue;
+
+        @PrefKey
+        public int intValue;
+
+        @PrefKey
+        public float floatValue;
+
+        @PrefKey
+        public long longValue;
+
+        @PrefKey
+        public boolean booleanValue;
+    }
+}
\ No newline at end of file
diff --git a/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest2.java b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest2.java
new file mode 100644
index 0000000..bd14656
--- /dev/null
+++ b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest2.java
@@ -0,0 +1,167 @@
+package com.os.operando.garum.models;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.support.test.runner.AndroidJUnit4;
+import android.test.ApplicationTestCase;
+
+import com.os.operando.garum.Garum;
+import com.os.operando.garum.annotations.Pref;
+import com.os.operando.garum.annotations.PrefKey;
+
+import junit.framework.Assert;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+// PrefName of PrefModel test.
+@RunWith(AndroidJUnit4.class)
+public class PrefModelTest2 extends ApplicationTestCase<Application> {
+
+    public PrefModelTest2() {
+        super(Application.class);
+    }
+
+    @Before
+    public void setUp() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+
+        Garum.initialize(getContext());
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+    }
+
+    // Test of raw preferences.
+    @Test
+    public void test1() {
+        Model model = new Model();
+        boolean result = model.save();
+        Assert.assertTrue(result); // Check save
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertFalse(prefs.contains("stringValue"));
+        Assert.assertFalse(prefs.contains("intValue"));
+        Assert.assertFalse(prefs.contains("floatValue"));
+        Assert.assertFalse(prefs.contains("longValue"));
+        Assert.assertFalse(prefs.contains("booleanValue"));
+
+        Assert.assertFalse(prefs.contains("PrefA")); // String value isn't exist if it's null.
+        Assert.assertTrue(prefs.contains("PrefB"));
+        Assert.assertTrue(prefs.contains("PrefC"));
+        Assert.assertTrue(prefs.contains("PrefD"));
+        Assert.assertTrue(prefs.contains("PrefE"));
+    }
+
+    // Test of raw preferences values.
+    @Test
+    public void test2() {
+        Model model = new Model();
+        model.stringValue = "keep it simple stupid.";
+        model.intValue = 34565;
+        model.floatValue = 543.22f;
+        model.longValue = 123432L;
+        model.booleanValue = true;
+        boolean result = model.save();
+        Assert.assertTrue(result); // Check save
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("PrefA"));
+        Assert.assertTrue(prefs.contains("PrefB"));
+        Assert.assertTrue(prefs.contains("PrefC"));
+        Assert.assertTrue(prefs.contains("PrefD"));
+        Assert.assertTrue(prefs.contains("PrefE"));
+
+        Assert.assertEquals("keep it simple stupid.", prefs.getString("PrefA", "DEFAULT"));
+        Assert.assertEquals(34565, prefs.getInt("PrefB", 6503));
+        Assert.assertEquals(543.22f, prefs.getFloat("PrefC", 204.3f));
+        Assert.assertEquals(123432L, prefs.getLong("PrefD", 3407L));
+        Assert.assertEquals(true, prefs.getBoolean("PrefE", false));
+    }
+
+    // Test of load.
+    @Test
+    public void test3() {
+        Model model = new Model();
+        model.stringValue = "keep it simple stupid.";
+        model.intValue = 34565;
+        model.floatValue = 543.22f;
+        model.longValue = 123432L;
+        model.booleanValue = true;
+        model.save();
+
+        // Load data
+        model = new Model();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("PrefA"));
+        Assert.assertTrue(prefs.contains("PrefB"));
+        Assert.assertTrue(prefs.contains("PrefC"));
+        Assert.assertTrue(prefs.contains("PrefD"));
+        Assert.assertTrue(prefs.contains("PrefE"));
+
+        Assert.assertEquals("keep it simple stupid.", prefs.getString("PrefA", "DEFAULT"));
+        Assert.assertEquals(34565, prefs.getInt("PrefB", 6503));
+        Assert.assertEquals(543.22f, prefs.getFloat("PrefC", 204.3f));
+        Assert.assertEquals(123432L, prefs.getLong("PrefD", 3407L));
+        Assert.assertEquals(true, prefs.getBoolean("PrefE", false));
+
+        Assert.assertEquals("keep it simple stupid.", model.stringValue);
+        Assert.assertEquals(34565, model.intValue);
+        Assert.assertEquals(543.22f, model.floatValue);
+        Assert.assertEquals(123432L, model.longValue);
+        Assert.assertEquals(true, model.booleanValue);
+    }
+
+    // Clear check.
+    @Test
+    public void test4() {
+        Model model = new Model();
+        model.stringValue = "keep it simple stupid.";
+        model.intValue = 34565;
+        model.floatValue = 543.22f;
+        model.longValue = 123432L;
+        model.booleanValue = true;
+        model.save();
+
+        model.clear();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertFalse(prefs.contains("PrefA"));
+        Assert.assertFalse(prefs.contains("PrefB"));
+        Assert.assertFalse(prefs.contains("PrefC"));
+        Assert.assertFalse(prefs.contains("PrefD"));
+        Assert.assertFalse(prefs.contains("PrefE"));
+
+        Assert.assertNull(model.stringValue);
+        Assert.assertEquals(0, model.intValue);
+        Assert.assertEquals(0f, model.floatValue);
+        Assert.assertEquals(0L, model.longValue);
+        Assert.assertEquals(false, model.booleanValue);
+    }
+
+    @Pref(name = "model")
+    public static class Model extends PrefModel {
+        @PrefKey("PrefA")
+        public String stringValue;
+
+        @PrefKey("PrefB")
+        public int intValue;
+
+        @PrefKey("PrefC")
+        public float floatValue;
+
+        @PrefKey("PrefD")
+        public long longValue;
+
+        @PrefKey("PrefE")
+        public boolean booleanValue;
+    }
+}
\ No newline at end of file
diff --git a/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest3.java b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest3.java
new file mode 100644
index 0000000..d6612f1
--- /dev/null
+++ b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest3.java
@@ -0,0 +1,112 @@
+package com.os.operando.garum.models;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.support.test.runner.AndroidJUnit4;
+import android.test.ApplicationTestCase;
+
+import com.os.operando.garum.Garum;
+import com.os.operando.garum.annotations.DefaultBoolean;
+import com.os.operando.garum.annotations.DefaultFloat;
+import com.os.operando.garum.annotations.DefaultInt;
+import com.os.operando.garum.annotations.DefaultLong;
+import com.os.operando.garum.annotations.DefaultString;
+import com.os.operando.garum.annotations.Pref;
+import com.os.operando.garum.annotations.PrefKey;
+
+import junit.framework.Assert;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+// Default annotation test.
+@RunWith(AndroidJUnit4.class)
+public class PrefModelTest3 extends ApplicationTestCase<Application> {
+
+    public PrefModelTest3() {
+        super(Application.class);
+    }
+
+    @Before
+    public void setUp() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+
+        Garum.initialize(getContext());
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+    }
+
+    // Test of raw preferences.
+    @Test
+    public void test1() {
+        Model model = new Model();
+        boolean result = model.save();
+        Assert.assertTrue(result); // Check save
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("stringValue"));
+        Assert.assertTrue(prefs.contains("intValue"));
+        Assert.assertTrue(prefs.contains("floatValue"));
+        Assert.assertTrue(prefs.contains("longValue"));
+        Assert.assertTrue(prefs.contains("booleanValue"));
+
+        Assert.assertEquals("keep it simple stupid.", prefs.getString("stringValue", "DEFAULT"));
+        Assert.assertEquals(34565, prefs.getInt("intValue", 6503));
+        Assert.assertEquals(543.22f, prefs.getFloat("floatValue", 204.3f));
+        Assert.assertEquals(123432L, prefs.getLong("longValue", 3407L));
+        Assert.assertEquals(true, prefs.getBoolean("booleanValue", false));
+    }
+
+    // Test of #clear method.
+    @Test
+    public void test2() {
+        Model model = new Model();
+        model.save();
+
+        model.clear();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertFalse(prefs.contains("stringValue"));
+        Assert.assertFalse(prefs.contains("intValue"));
+        Assert.assertFalse(prefs.contains("floatValue"));
+        Assert.assertFalse(prefs.contains("longValue"));
+        Assert.assertFalse(prefs.contains("booleanValue"));
+
+        Assert.assertEquals("keep it simple stupid.", model.stringValue);
+        Assert.assertEquals(34565, model.intValue);
+        Assert.assertEquals(543.22f, model.floatValue);
+        Assert.assertEquals(123432L, model.longValue);
+        Assert.assertEquals(true, model.booleanValue);
+    }
+
+    @Pref(name = "model")
+    public static class Model extends PrefModel {
+        @PrefKey
+        @DefaultString("keep it simple stupid.")
+        public String stringValue;
+
+        @PrefKey
+        @DefaultInt(34565)
+        public int intValue;
+
+        @PrefKey
+        @DefaultFloat(543.22f)
+        public float floatValue;
+
+        @PrefKey
+        @DefaultLong(123432L)
+        public long longValue;
+
+        @PrefKey
+        @DefaultBoolean(true)
+        public boolean booleanValue;
+    }
+}
\ No newline at end of file
diff --git a/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest4.java b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest4.java
new file mode 100644
index 0000000..647669e
--- /dev/null
+++ b/garum/src/androidTest/java/com/os/operando/garum/models/PrefModelTest4.java
@@ -0,0 +1,132 @@
+package com.os.operando.garum.models;
+
+import android.app.Application;
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.support.test.runner.AndroidJUnit4;
+import android.test.ApplicationTestCase;
+
+import com.os.operando.garum.Garum;
+import com.os.operando.garum.annotations.Pref;
+import com.os.operando.garum.annotations.PrefKey;
+
+import junit.framework.Assert;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.util.Date;
+
+@RunWith(AndroidJUnit4.class)
+public class PrefModelTest4 extends ApplicationTestCase<Application> {
+
+    public PrefModelTest4() {
+        super(Application.class);
+    }
+
+    @Before
+    public void setUp() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+
+        Garum.initialize(getContext());
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        // Clear a model pref.
+        getContext().getSharedPreferences("model", Context.MODE_PRIVATE).edit().clear().commit();
+    }
+
+    // Test of raw preferences.
+    @Test
+    public void test1() {
+        Model model = new Model();
+        boolean result = model.save();
+        Assert.assertTrue(result); // Check save
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertFalse(prefs.contains("date"));
+        Assert.assertFalse(prefs.contains("json"));
+
+        Assert.assertNull(model.date);
+        Assert.assertNull(model.json);
+    }
+
+    @Test
+    public void test2() throws JSONException {
+        String jsonString = "{\"screen_name\":\"katty0324\",\"age\":23}";
+        JSONObject jsonObject = new JSONObject(jsonString);
+        Date date = new Date();
+
+        Model model = new Model();
+        model.date = date;
+        model.json = jsonObject;
+        model.save();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("date"));
+        Assert.assertTrue(prefs.contains("json"));
+    }
+
+    // Test of load.
+    @Test
+    public void test3() throws JSONException {
+        String jsonString = "{\"screen_name\":\"katty0324\",\"age\":23}";
+        JSONObject jsonObject = new JSONObject(jsonString);
+        Date date = new Date();
+
+        Model model = new Model();
+        model.date = date;
+        model.json = jsonObject;
+        model.save();
+
+        // Load data
+        model = new Model();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertTrue(prefs.contains("date"));
+        Assert.assertTrue(prefs.contains("json"));
+
+        Assert.assertEquals(date, model.date);
+        Assert.assertEquals("katty0324", model.json.getString("screen_name"));
+        Assert.assertEquals("katty0324", jsonObject.getString("screen_name"));
+        Assert.assertEquals(23, model.json.getInt("age"));
+        Assert.assertEquals(23, jsonObject.getInt("age"));
+    }
+
+    // Test of #clear method.
+    @Test
+    public void test4() throws JSONException {
+        String jsonString = "{\"screen_name\":\"katty0324\",\"age\":23}";
+        JSONObject jsonObject = new JSONObject(jsonString);
+        Date date = new Date();
+
+        Model model = new Model();
+        model.date = date;
+        model.json = jsonObject;
+        model.save();
+
+        model.clear();
+
+        SharedPreferences prefs = getContext().getSharedPreferences("model", Context.MODE_PRIVATE);
+        Assert.assertFalse(prefs.contains("date"));
+        Assert.assertFalse(prefs.contains("json"));
+
+        Assert.assertNull(model.date);
+        Assert.assertNull(model.json);
+    }
+
+    @Pref(name = "model")
+    public static class Model extends PrefModel {
+        @PrefKey
+        public Date date;
+
+        @PrefKey
+        public JSONObject json;
+    }
+}
\ No newline at end of file