diff --git a/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/FeatureChangesPgListener.java b/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/FeatureChangesPgListener.java
index 26e21888a..448013c80 100644
--- a/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/FeatureChangesPgListener.java
+++ b/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/FeatureChangesPgListener.java
@@ -27,9 +27,9 @@
 import de.ii.xtraplatform.features.sql.domain.SqlClient;
 import de.ii.xtraplatform.features.sql.domain.SqlConnector;
 import de.ii.xtraplatform.features.sql.domain.SqlDbmsPgis;
-import java.sql.Connection;
-import java.sql.SQLException;
-import java.sql.Statement;
+import java.sql.Connection; // NOPMD
+import java.sql.SQLException; // NOPMD
+import java.sql.Statement; // NOPMD
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -78,6 +78,7 @@
  */
 @Singleton
 @AutoBind
+@SuppressWarnings("PMD.DoNotUseThreads")
 public class FeatureChangesPgListener implements FeatureQueriesExtension {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(FeatureChangesPgListener.class);
@@ -105,9 +106,11 @@ public boolean isSupported(
       return false;
     }
     if (!((FeatureProviderSqlData) data).getDatasetChanges().isModeTrigger()) {
-      LOGGER.warn(
-          "Feature provider with id '{}' does not support change listeners: datasetChanges.mode is not 'TRIGGER'",
-          data.getId());
+      if (LOGGER.isWarnEnabled()) {
+        LOGGER.warn(
+            "Feature provider with id '{}' does not support change listeners: datasetChanges.mode is not 'TRIGGER'",
+            data.getId());
+      }
       return false;
     }
 
@@ -122,15 +125,10 @@ public void on(
     Optional<FeatureChangesPgConfiguration> configuration =
         getConfiguration(provider.getData().getExtensions());
 
-    if (configuration.isPresent()) {
+    if (configuration.isPresent() && hook == LIFECYCLE_HOOK.STARTED) {
       SqlClient sqlClient = ((SqlConnector) connector).getSqlClient();
-
-      switch (hook) {
-        case STARTED:
-          subscribe(
-              provider, configuration.get(), sqlClient::getConnection, sqlClient::getNotifications);
-          break;
-      }
+      subscribe(
+          provider, configuration.get(), sqlClient::getConnection, sqlClient::getNotifications);
     }
   }
 
@@ -211,7 +209,9 @@ private void poll(String provider, FeatureChanges featureChangeHandler) {
   private void poll(
       String provider, FeatureChanges featureChangeHandler, Subscription subscription) {
     if (!subscription.isConnected()) {
-      LOGGER.debug("Lost connection to retrieve feature changes for {}", subscription.getLabel());
+      if (LOGGER.isDebugEnabled()) {
+        LOGGER.debug("Lost connection to retrieve feature changes for {}", subscription.getLabel());
+      }
       subscriptions.get(provider).remove(subscription.getChannel());
       subscribe(provider, subscription);
 
@@ -250,8 +250,9 @@ private List<Subscription> getSubscriptions(
     includes.forEach(
         include -> {
           if (types.stream()
-              .map(FeatureSchema::getName)
-              .noneMatch(type -> Objects.equals(type, include))) {
+                  .map(FeatureSchema::getName)
+                  .noneMatch(type -> Objects.equals(type, include))
+              && LOGGER.isWarnEnabled()) {
             LOGGER.warn("Change listener: unknown type '{}' in listenForTypes", include);
           }
         });
diff --git a/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Notification.java b/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Notification.java
index 599eab514..6ab177119 100644
--- a/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Notification.java
+++ b/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Notification.java
@@ -24,6 +24,8 @@
 @Value.Immutable
 public interface Notification {
 
+  Splitter SPLITTER = Splitter.on(",").trimResults();
+
   static Notification from(String featureType, String payload) {
     return ImmutableNotification.builder().featureType(featureType).payload(payload).build();
   }
@@ -55,22 +57,22 @@ default FeatureChange asFeatureChange() {
         .build();
   }
 
-  Splitter SPLITTER = Splitter.on(",").trimResults();
-
   private static List<String> parseFeatureId(String featureId) {
-    if (featureId.isEmpty() || featureId.equalsIgnoreCase("NULL")) return ImmutableList.of();
+    if (featureId.isEmpty() || "NULL".equalsIgnoreCase(featureId)) {
+      return ImmutableList.of();
+    }
 
     return ImmutableList.of(featureId);
   }
 
   private static Optional<Interval> parseInterval(List<String> interval) {
-    if (interval.get(0).isEmpty()) {
-      // no instant or interval, ignore
-    } else if (interval.get(1).isEmpty()) {
+    if (interval.get(1).isEmpty()) {
       // an instant
       try {
         Instant instant = parseTimestamp(interval.get(0));
-        if (Objects.nonNull(instant)) return Optional.of(Interval.of(instant, instant));
+        if (Objects.nonNull(instant)) {
+          return Optional.of(Interval.of(instant, instant));
+        }
       } catch (Exception e) {
         // ignore
       }
diff --git a/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Subscription.java b/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Subscription.java
index ff6d30647..60a248bbe 100644
--- a/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Subscription.java
+++ b/xtraplatform-feature-changes-sql/src/main/java/de/ii/xtraplatform/feature/changes/sql/app/Subscription.java
@@ -9,8 +9,8 @@
 
 import com.google.common.base.Strings;
 import de.ii.xtraplatform.base.domain.util.Tuple;
-import java.sql.Connection;
-import java.sql.SQLException;
+import java.sql.Connection; // NOPMD
+import java.sql.SQLException; // NOPMD
 import java.util.List;
 import java.util.Optional;
 import java.util.function.Function;