diff --git a/src/main/java/de/tudbut/security/PermissionManager.java b/src/main/java/de/tudbut/security/PermissionManager.java
index 5d4748e..007f978 100644
--- a/src/main/java/de/tudbut/security/PermissionManager.java
+++ b/src/main/java/de/tudbut/security/PermissionManager.java
@@ -41,7 +41,7 @@ public interface PermissionManager extends Cloneable {
         return getClassName(clazz, null, 0);
     }
     default String getClassName(Class<?> clazz, boolean[] cache, int idx) {
-        if(cache != null && cache[0])
+        if(cache != null && cache[idx])
             return clazz.getName();
         try {
             // Reset the name field so that it must be cached again
diff --git a/src/main/java/de/tudbut/security/permissionmanager/CallClassRestriction.java b/src/main/java/de/tudbut/security/permissionmanager/CallClassRestriction.java
index 7e9049c..defbb61 100644
--- a/src/main/java/de/tudbut/security/permissionmanager/CallClassRestriction.java
+++ b/src/main/java/de/tudbut/security/permissionmanager/CallClassRestriction.java
@@ -55,8 +55,8 @@ public class CallClassRestriction extends Restriction {
             // is class, inner class of it, loaded by it, or lambda in it?
             Class<?> enclosingClass = lambda.getClass().getEnclosingClass();
             boolean[] cache = new boolean[2];
-            b = allow.contains(getClassName(lambda.getClass(), cache, 0))
-                    || allow.contains(getClassName(lambda.getClass(), cache, 0).replaceAll("\\$\\$Lambda.*$", ""));
+            b = allow.contains(getClassName(lambda.getClass()))
+                    || allow.contains(getClassName(lambda.getClass()).replaceAll("\\$\\$Lambda.*$", ""));
             if (enclosingClass != null)
                 b = b || allow.contains(getClassName(enclosingClass));
         }
diff --git a/src/main/java/de/tudbut/security/permissionmanager/ClassLoaderRestriction.java b/src/main/java/de/tudbut/security/permissionmanager/ClassLoaderRestriction.java
index edb1feb..5c65080 100644
--- a/src/main/java/de/tudbut/security/permissionmanager/ClassLoaderRestriction.java
+++ b/src/main/java/de/tudbut/security/permissionmanager/ClassLoaderRestriction.java
@@ -94,9 +94,8 @@ public class ClassLoaderRestriction extends Restriction {
                 b = b || allow.stream().anyMatch(x -> x.getClass() == enclosingClass);
 
             // is lambda in allowed class?
-            boolean[] cache = new boolean[1];
-            String name = getClassName(lambda.getClass(), cache, 0).replaceAll("\\$\\$Lambda.*$", "");
-            b = b || allow.stream().anyMatch(x -> getClassName(x.getClass(), cache, 0).equals(name)); // is lambda in classloader
+            String name = getClassName(lambda.getClass()).replaceAll("\\$\\$Lambda.*$", "");
+            b = b || allow.stream().anyMatch(x -> getClassName(x.getClass()).equals(name)); // is lambda in classloader
             try {
                 b = b || allow.contains(getClassObject(name).getClassLoader()); // is lambda in classloader-loaded class
             } catch (Exception e) {