From ce1099905e73478c1e6762d33afc4af7965a63a5 Mon Sep 17 00:00:00 2001
From: Florian Fendt <Florian.Fendt@bosch-si.com>
Date: Fri, 8 Mar 2019 11:42:59 +0100
Subject: [PATCH] use UnaryOperator

---
 .../messaging/persistence/ConnectionMigrationUtil.java     | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/services/connectivity/messaging/src/main/java/org/eclipse/ditto/services/connectivity/messaging/persistence/ConnectionMigrationUtil.java b/services/connectivity/messaging/src/main/java/org/eclipse/ditto/services/connectivity/messaging/persistence/ConnectionMigrationUtil.java
index 428f4939c4..8d9f693b8f 100644
--- a/services/connectivity/messaging/src/main/java/org/eclipse/ditto/services/connectivity/messaging/persistence/ConnectionMigrationUtil.java
+++ b/services/connectivity/messaging/src/main/java/org/eclipse/ditto/services/connectivity/messaging/persistence/ConnectionMigrationUtil.java
@@ -11,7 +11,6 @@
 package org.eclipse.ditto.services.connectivity.messaging.persistence;
 
 import java.util.Optional;
-import java.util.function.Function;
 import java.util.function.UnaryOperator;
 import java.util.regex.Pattern;
 import java.util.stream.IntStream;
@@ -63,9 +62,9 @@ private ConnectionMigrationUtil() {
      * @return the (potentially migrated) Connection instance
      */
     static Connection connectionFromJsonWithMigration(@Nonnull final JsonObject connectionJsonObject) {
-        final Function<JsonObject, JsonObject> migrateSourceFilters = new MigrateSourceFilters();
-        final Function<JsonObject, JsonObject> migrateTopicActionSubjectFilters = new MigrateTopicActionSubjectFilters();
-        final Function<JsonObject, JsonObject> migrateAuthorizationContexts = new MigrateAuthorizationContexts();
+        final UnaryOperator<JsonObject> migrateSourceFilters = new MigrateSourceFilters();
+        final UnaryOperator<JsonObject> migrateTopicActionSubjectFilters = new MigrateTopicActionSubjectFilters();
+        final UnaryOperator<JsonObject> migrateAuthorizationContexts = new MigrateAuthorizationContexts();
 
         return ConnectivityModelFactory.connectionFromJson(
                 migrateAuthorizationContexts