diff --git a/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/ActionFields.java b/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/ActionFields.java
index 3a1e49bed..5b40f7ad5 100644
--- a/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/ActionFields.java
+++ b/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/ActionFields.java
@@ -9,7 +9,6 @@
  */
 package org.eclipse.hawkbit.repository;
 
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 
diff --git a/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/FieldValueConverter.java b/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/FieldValueConverter.java
index 9283784e0..4d84fa638 100644
--- a/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/FieldValueConverter.java
+++ b/hawkbit-core/src/main/java/org/eclipse/hawkbit/repository/FieldValueConverter.java
@@ -23,9 +23,9 @@ public interface FieldValueConverter<T extends Enum<T>> {
     /**
      * Converts the given {@code value} into the representation to build ageneric query.
      *
-     * @param enumValue the enum to build the value for
+     * @param enumValue the enum value to build the value for
      * @param value the value in string representation
-     * @return the converted object or {@code null} if conversation fails, if given enum does not need to be converted the
+     * @return the converted object if conversion is applicable, or if the given enum value does not need to be converted the
      *         unmodified {@code value} is returned.
      * @throws IllegalArgumentException if the value is not supported
      */
diff --git a/hawkbit-repository/hawkbit-repository-api/src/main/java/org/eclipse/hawkbit/repository/rsql/RsqlConfigHolder.java b/hawkbit-repository/hawkbit-repository-api/src/main/java/org/eclipse/hawkbit/repository/rsql/RsqlConfigHolder.java
index 3835ac33e..b72094be1 100644
--- a/hawkbit-repository/hawkbit-repository-api/src/main/java/org/eclipse/hawkbit/repository/rsql/RsqlConfigHolder.java
+++ b/hawkbit-repository/hawkbit-repository-api/src/main/java/org/eclipse/hawkbit/repository/rsql/RsqlConfigHolder.java
@@ -11,7 +11,6 @@ package org.eclipse.hawkbit.repository.rsql;
 
 import lombok.Getter;
 import lombok.NoArgsConstructor;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.beans.factory.annotation.Value;
 
 /**