diff --git a/src/main/java/com/eclipsesource/v8/V8.java b/src/main/java/com/eclipsesource/v8/V8.java
index 117934c74..eeaedd206 100644
--- a/src/main/java/com/eclipsesource/v8/V8.java
+++ b/src/main/java/com/eclipsesource/v8/V8.java
@@ -100,7 +100,7 @@ public void executeVoidScript(final String script) throws V8RuntimeException {
         _executeVoidScript(v8RuntimeHandle, script);
     }
 
-    void checkThread() {
+    static void checkThread() {
         if (thread != Thread.currentThread()) {
             throw new Error("Invalid V8 thread access.");
         }
diff --git a/src/main/java/com/eclipsesource/v8/V8Array.java b/src/main/java/com/eclipsesource/v8/V8Array.java
index 0294ca4e5..b0479e652 100644
--- a/src/main/java/com/eclipsesource/v8/V8Array.java
+++ b/src/main/java/com/eclipsesource/v8/V8Array.java
@@ -10,50 +10,50 @@ public class V8Array {
 
     public V8Array(final V8 v8) {
         this.v8 = v8;
-        this.v8.checkThread();
+        V8.checkThread();
         arrayHandle = v8ArrayInstanceCounter++;
         this.v8._initNewV8Array(v8.getV8RuntimeHandle(), arrayHandle);
         this.v8.addObjRef();
     }
 
     public void release() {
-        v8.checkThread();
+        V8.checkThread();
         v8._releaseArray(v8.getV8RuntimeHandle(), arrayHandle);
         v8.releaseObjRef();
     }
 
     public int getSize() {
-        v8.checkThread();
+        V8.checkThread();
         return v8._arrayGetSize(v8.getV8RuntimeHandle(), getHandle());
     }
 
     public int getType(final int index) {
-        v8.checkThread();
+        V8.checkThread();
         return v8._getType(v8.getV8RuntimeHandle(), getHandle(), index);
     }
 
     public int getInteger(final int index) {
-        v8.checkThread();
+        V8.checkThread();
         return v8._arrayGetInteger(v8.getV8RuntimeHandle(), getHandle(), index);
     }
 
     public boolean getBoolean(final int index) {
-        v8.checkThread();
+        V8.checkThread();
         return v8._arrayGetBoolean(v8.getV8RuntimeHandle(), getHandle(), index);
     }
 
     public double getDouble(final int index) {
-        v8.checkThread();
+        V8.checkThread();
         return v8._arrayGetDouble(v8.getV8RuntimeHandle(), getHandle(), index);
     }
 
     public String getString(final int index) {
-        v8.checkThread();
+        V8.checkThread();
         return v8._arrayGetString(v8.getV8RuntimeHandle(), getHandle(), index);
     }
 
     public V8Array getArray(final int index) {
-        v8.checkThread();
+        V8.checkThread();
         V8Array result = new V8Array(v8);
         try {
             v8._arrayGetArray(v8.getV8RuntimeHandle(), getHandle(), index, result.getHandle());
@@ -65,7 +65,7 @@ public V8Array getArray(final int index) {
     }
 
     public V8Object getObject(final int index) {
-        v8.checkThread();
+        V8.checkThread();
         V8Object result = new V8Object(v8);
         try {
             v8._arrayGetObject(v8.getV8RuntimeHandle(), getHandle(), index, result.getHandle());
@@ -77,32 +77,32 @@ public V8Object getObject(final int index) {
     }
 
     public void add(final int value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addArrayIntItem(v8.getV8RuntimeHandle(), getHandle(), value);
     }
 
     public void add(final boolean value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addArrayBooleanItem(v8.getV8RuntimeHandle(), getHandle(), value);
     }
 
     public void add(final double value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addArrayDoubleItem(v8.getV8RuntimeHandle(), getHandle(), value);
     }
 
     public void add(final String value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addArrayStringItem(v8.getV8RuntimeHandle(), getHandle(), value);
     }
 
     public void add(final V8Object value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addArrayObjectItem(v8.getV8RuntimeHandle(), getHandle(), value.getHandle());
     }
 
     public void add(final V8Array value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addArrayArrayItem(v8.getV8RuntimeHandle(), getHandle(), value.getHandle());
     }
 
diff --git a/src/main/java/com/eclipsesource/v8/V8Object.java b/src/main/java/com/eclipsesource/v8/V8Object.java
index 69d10ec24..81a50badd 100644
--- a/src/main/java/com/eclipsesource/v8/V8Object.java
+++ b/src/main/java/com/eclipsesource/v8/V8Object.java
@@ -25,7 +25,7 @@ protected V8Object() {
 
     public V8Object(final V8 v8) {
         this.v8 = v8;
-        this.v8.checkThread();
+        V8.checkThread();
         objectHandle = v8ObjectInstanceCounter++;
         this.v8._initNewV8Object(v8.getV8RuntimeHandle(), objectHandle);
         this.v8.addObjRef();
@@ -36,48 +36,48 @@ public int getHandle() {
     }
 
     public void release() {
-        v8.checkThread();
+        V8.checkThread();
         v8._release(v8.getV8RuntimeHandle(), objectHandle);
         v8.releaseObjRef();
     }
 
     public boolean contains(final String key) {
-        v8.checkThread();
+        V8.checkThread();
         return v8._contains(v8.getV8RuntimeHandle(), objectHandle, key);
     }
 
     public String[] getKeys() {
-        v8.checkThread();
+        V8.checkThread();
         return v8._getKeys(v8.getV8RuntimeHandle(), objectHandle);
     }
 
     public int getType(final String key) throws V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         return v8._getType(v8.getV8RuntimeHandle(), objectHandle, key);
     }
 
     public int getInteger(final String key) throws V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         return v8._getInteger(v8.getV8RuntimeHandle(), objectHandle, key);
     }
 
     public boolean getBoolean(final String key) throws V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         return v8._getBoolean(v8.getV8RuntimeHandle(), objectHandle, key);
     }
 
     public double getDouble(final String key) throws V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         return v8._getDouble(v8.getV8RuntimeHandle(), objectHandle, key);
     }
 
     public String getString(final String key) throws V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         return v8._getString(v8.getV8RuntimeHandle(), objectHandle, key);
     }
 
     public V8Array getArray(final String key) throws V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         V8Array result = new V8Array(v8);
         try {
             v8._getArray(v8.getV8RuntimeHandle(), getHandle(), key, result.getHandle());
@@ -89,7 +89,7 @@ public V8Array getArray(final String key) throws V8ResultUndefined {
     }
 
     public V8Object getObject(final String key) throws V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         V8Object result = new V8Object(v8);
         try {
             v8._getObject(v8.getV8RuntimeHandle(), objectHandle, key, result.getHandle());
@@ -101,37 +101,37 @@ public V8Object getObject(final String key) throws V8ResultUndefined {
     }
 
     public V8Array createParameterList(final int size) {
-        v8.checkThread();
+        V8.checkThread();
         return null;
     }
 
     public int executeIntFunction(final String name, final V8Array parameters) throws V8ExecutionException, V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         int parametersHandle = parameters == null ? -1 : parameters.getHandle();
         return v8._executeIntFunction(v8.getV8RuntimeHandle(), getHandle(), name, parametersHandle);
     }
 
     public double executeDoubleFunction(final String name, final V8Array parameters) throws V8ExecutionException, V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         int parametersHandle = parameters == null ? -1 : parameters.getHandle();
         return v8._executeDoubleFunction(v8.getV8RuntimeHandle(), getHandle(), name, parametersHandle);
     }
 
     public String executeStringFunction(final String name, final V8Array parameters) throws V8ExecutionException, V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         int parametersHandle = parameters == null ? -1 : parameters.getHandle();
         return v8._executeStringFunction(v8.getV8RuntimeHandle(), getHandle(), name, parametersHandle);
     }
 
     public boolean executeBooleanFunction(final String name, final V8Array parameters) throws V8ExecutionException,
     V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         int parametersHandle = parameters == null ? -1 : parameters.getHandle();
         return v8._executeBooleanFunction(v8.getV8RuntimeHandle(), getHandle(), name, parametersHandle);
     }
 
     public V8Array executeArrayFunction(final String name, final V8Array parameters) throws V8ExecutionException, V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         V8Array result = new V8Array(v8);
         try {
             int parametersHandle = parameters == null ? -1 : parameters.getHandle();
@@ -146,7 +146,7 @@ public V8Array executeArrayFunction(final String name, final V8Array parameters)
 
     public V8Object executeObjectFunction(final String name, final V8Array parameters) throws V8ExecutionException,
     V8ResultUndefined {
-        v8.checkThread();
+        V8.checkThread();
         V8Object result = new V8Object(v8);
         try {
             int parametersHandle = parameters == null ? -1 : parameters.getHandle();
@@ -159,48 +159,49 @@ public V8Object executeObjectFunction(final String name, final V8Array parameter
     }
 
     public void executeVoidFunction(final String name, final V8Array parameters) throws V8ExecutionException {
-        v8.checkThread();
+        V8.checkThread();
         int parametersHandle = parameters == null ? -1 : parameters.getHandle();
         v8._executeVoidFunction(v8.getV8RuntimeHandle(), objectHandle, name, parametersHandle);
     }
 
     public void add(final String key, final int value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._add(v8.getV8RuntimeHandle(), objectHandle, key, value);
     }
 
     public void add(final String key, final boolean value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._add(v8.getV8RuntimeHandle(), objectHandle, key, value);
     }
 
     public void add(final String key, final double value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._add(v8.getV8RuntimeHandle(), objectHandle, key, value);
     }
 
     public void add(final String key, final String value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._add(v8.getV8RuntimeHandle(), objectHandle, key, value);
     }
 
     public void add(final String key, final V8Object value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addObject(v8.getV8RuntimeHandle(), objectHandle, key, value.getHandle());
     }
 
     public void add(final String key, final V8Array value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._addArray(v8.getV8RuntimeHandle(), objectHandle, key, value.getHandle());
     }
 
     public void setPrototype(final V8Object value) {
-        v8.checkThread();
+        V8.checkThread();
         v8._setPrototype(v8.getV8RuntimeHandle(), objectHandle, value.getHandle());
     }
 
     public void registerJavaMethod(final Object object, final String methodName, final String jsFunctionName,
             final Class<?>[] parameterTypes) {
+        V8.checkThread();
         try {
             Method method = object.getClass().getMethod(methodName, parameterTypes);
             v8.registerCallback(object, method, 0, getHandle(), jsFunctionName);
@@ -209,7 +210,6 @@ public void registerJavaMethod(final Object object, final String methodName, fin
         } catch (SecurityException e) {
             throw new IllegalStateException(e);
         }
-        v8.checkThread();
     }
 
 }