diff --git a/pom.xml b/pom.xml
index 1bb5a43..b231cd7 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,7 +5,7 @@
 
     <groupId>com.featureprobe</groupId>
     <artifactId>server-sdk-java</artifactId>
-    <version>2.2.2</version>
+    <version>2.3.0</version>
     <name>server-sdk-java</name>
     <description>FeatureProbe Server Side SDK for Java</description>
 
diff --git a/src/main/java/com/featureprobe/sdk/server/model/Toggle.java b/src/main/java/com/featureprobe/sdk/server/model/Toggle.java
index 8f88fbf..6afdb59 100644
--- a/src/main/java/com/featureprobe/sdk/server/model/Toggle.java
+++ b/src/main/java/com/featureprobe/sdk/server/model/Toggle.java
@@ -27,7 +27,7 @@
 import java.util.Objects;
 import java.util.Optional;
 
-public final class Toggle {
+public class Toggle {
 
     private String key;
 
@@ -53,7 +53,7 @@ public final class Toggle {
 
     public EvaluationResult eval(FPUser user, Map<String, Toggle> toggles, Map<String, Segment> segments,
                                  Object defaultValue, int deep) {
-        EvaluationResult result = createDefaultResult(user, key, defaultValue, "");
+        EvaluationResult result = createDisabledResult(user, key, defaultValue);
         try {
             return doEval(user, toggles, segments, defaultValue, deep);
         } catch (PrerequisiteException e) {
@@ -66,7 +66,7 @@ public EvaluationResult eval(FPUser user, Map<String, Toggle> toggles, Map<Strin
     }
 
     public EvaluationResult doEval(FPUser user, Map<String, Toggle> toggles, Map<String, Segment> segments,
-                                   Object defaultValue, int deep) {
+                                   Object defaultValue, int depth) {
 
         String warning = "";
 
@@ -74,15 +74,15 @@ public EvaluationResult doEval(FPUser user, Map<String, Toggle> toggles, Map<Str
             return createDisabledResult(user, this.key, defaultValue);
         }
 
-        if (deep <= 0) {
-            throw new PrerequisiteException("prerequisite deep overflow");
+        if (depth <= 0) {
+            throw new PrerequisiteException("prerequisite depth overflow");
         }
 
-        if (!prerequisite(user, toggles, segments, deep)) {
-            return createDefaultResult(user, key, defaultValue, warning);
+        if (!meetPrerequisite(user, toggles, segments, depth)) {
+            return createDisabledResult(user, key, defaultValue);
         }
 
-        if (rules != null && rules.size() > 0) {
+        if (rules != null && !rules.isEmpty()) {
             for (int i = 0; i < rules.size(); i++) {
                 Rule rule = rules.get(i);
                 HitResult hitResult = rule.hit(user, segments, this.key);
@@ -110,7 +110,8 @@ private EvaluationResult createDefaultResult(FPUser user, String toggleKey, Obje
         return defaultResult;
     }
 
-    private boolean prerequisite(FPUser user, Map<String, Toggle> toggles, Map<String, Segment> segments, int deep) {
+    protected boolean meetPrerequisite(FPUser user, Map<String, Toggle> toggles, Map<String, Segment> segments,
+                                       int depth) {
         if (Objects.isNull(prerequisites) || prerequisites.isEmpty()) {
             return true;
         }
@@ -118,7 +119,7 @@ private boolean prerequisite(FPUser user, Map<String, Toggle> toggles, Map<Strin
             Toggle toggle = toggles.get(prerequisite.getKey());
             if (Objects.isNull(toggle))
                 throw new PrerequisiteException("prerequisite not exist: " + this.key);
-            EvaluationResult eval = toggle.doEval(user, toggles, segments, null, deep - 1);
+            EvaluationResult eval = toggle.doEval(user, toggles, segments, null, depth - 1);
             if (Objects.isNull(eval.getValue()))
                 return false;
             if (!eval.getValue().equals(prerequisite.getValue()))
diff --git a/src/test/groovy/com/featureprobe/sdk/server/FeatureProbeSpec.groovy b/src/test/groovy/com/featureprobe/sdk/server/FeatureProbeSpec.groovy
index ea854ea..027cb60 100644
--- a/src/test/groovy/com/featureprobe/sdk/server/FeatureProbeSpec.groovy
+++ b/src/test/groovy/com/featureprobe/sdk/server/FeatureProbeSpec.groovy
@@ -46,9 +46,11 @@ class FeatureProbeSpec extends Specification {
     }
 
 
-    def "FeatureProbe case test"() {
+    def "FeatureProbe Server Side Java SDK specification test"() {
         when:
         def tests = testCase.get("tests").asList()
+
+        then:
         for (int i = 0; i < tests.size(); i++) {
             def scenario = tests.get(i)
             def name = scenario.get("scenario").asText()
@@ -118,19 +120,13 @@ class FeatureProbeSpec extends Specification {
                         def stringDetailRes = featureProbe.stringDetail(toggleKey, user,
                                 defaultValue.asText())
                         assert stringDetailRes.value == expectValue.asText()
+                        if (expectResult.get("reason") != null) {
+                            assert stringDetailRes.reason.containsIgnoreCase(expectResult.get("reason").asText())
+                        }
                         break
                 }
             }
         }
-        then:
-        with(FeatureProbe) {
-
-        }
-    }
-
-
-    def "FeatureProbe repository uninitialized"() {
-
     }
 
 }
diff --git a/src/test/groovy/com/featureprobe/sdk/server/ToggleTest.groovy b/src/test/groovy/com/featureprobe/sdk/server/ToggleTest.groovy
new file mode 100644
index 0000000..31a7be4
--- /dev/null
+++ b/src/test/groovy/com/featureprobe/sdk/server/ToggleTest.groovy
@@ -0,0 +1,83 @@
+package com.featureprobe.sdk.server
+
+import com.featureprobe.sdk.server.model.Serve
+import com.featureprobe.sdk.server.model.Toggle
+import spock.lang.Specification
+
+class ToggleTest extends Specification {
+    def toggle = new Toggle()
+    def user = new FPUser();
+
+    def setup() {
+        toggle.setEnabled(Boolean.TRUE);
+        toggle.setVariations([0,1])
+        toggle.setDisabledServe(new Serve(0))
+        toggle.setDefaultServe(new Serve(1))
+    }
+
+    def "If toggle is disabled serve disabled variation"() {
+        given:
+        toggle.setEnabled(Boolean.FALSE)
+
+        when:
+        def result = toggle.doEval(user, null, null, null, 1)
+
+        then:
+        0 == result.variationIndex.get()
+    }
+
+    def "If toggle is enabled serve default variation"() {
+        given:
+        toggle.setEnabled(Boolean.TRUE)
+
+        when:
+        def result = toggle.doEval(user, null, null, null, 1)
+
+        then:
+        1 == result.variationIndex.get()
+    }
+
+    def "When meetPrerequisite returns false should act like disabled"() {
+        setup:
+        Toggle toggleSpy = Spy()
+        toggleSpy.enabled = true
+
+        final DEFAULT_VARIATION = 1
+        final DISABLED_VARIATION = 0
+
+        toggleSpy.variations = [DEFAULT_VARIATION, DISABLED_VARIATION]
+        toggleSpy.defaultServe = new Serve(DEFAULT_VARIATION)
+        toggleSpy.disabledServe = new Serve(DISABLED_VARIATION)
+
+        // Make meetPrerequisite return false
+        toggleSpy.meetPrerequisite(user, null, null, 1) >> false
+
+        when:
+        def result = toggleSpy.doEval(user, null, null, null, 1)
+
+        then:
+        DISABLED_VARIATION == result.variationIndex.get()
+    }
+
+    def "When meetPrerequisite returns true should not act like disabled"() {
+        setup:
+        Toggle toggleSpy = Spy()
+        toggleSpy.enabled = true
+        final DEFAULT_VARIATION = 1
+        final DISABLED_VARIATION = 0
+
+        toggleSpy.variations = [DEFAULT_VARIATION, DISABLED_VARIATION]
+        toggleSpy.defaultServe = new Serve(DEFAULT_VARIATION)
+        toggleSpy.disabledServe = new Serve(DISABLED_VARIATION)
+
+        // Make meetPrerequisite return false
+        toggleSpy.meetPrerequisite(user, null, null, 1) >> true
+
+        when:
+        def result = toggleSpy.doEval(user, null, null, null, 1)
+
+        then:
+        DISABLED_VARIATION != result.variationIndex.get()
+    }
+
+}
diff --git a/src/test/resources/test b/src/test/resources/test
index 90d81ec..503eec9 160000
--- a/src/test/resources/test
+++ b/src/test/resources/test
@@ -1 +1 @@
-Subproject commit 90d81ec82259a9814e3436efbfe899969b5b17e3
+Subproject commit 503eec9218dc0d2af9439ceaf652316ed1e500fa