Collections.emptyXXX + Collections.singletonXXX => List/Set/Map.of

2 files changed, 3 insertions, 5 deletions

diff --git a/config-model/src/main/java/com/yahoo/schema/derived/Deriver.java b/config-model/src/main/java/com/yahoo/schema/derived/Deriver.java
index 9774868db9c..0c669e29538 100644
--- a/config-model/src/main/java/com/yahoo/schema/derived/Deriver.java
+++ b/config-model/src/main/java/com/yahoo/schema/derived/Deriver.java
@@ -7,7 +7,6 @@ import com.yahoo.schema.parser.ParseException;
 import com.yahoo.vespa.configmodel.producers.DocumentManager;
 import com.yahoo.vespa.configmodel.producers.DocumentTypes;
 import java.io.IOException;
-import java.util.Collections;
 import java.util.List;
 
 /**
@@ -30,7 +29,7 @@ public class Deriver {
     }
 
     public static DocumentmanagerConfig.Builder getDocumentManagerConfig(String sd) {
-        return getDocumentManagerConfig(Collections.singletonList(sd));
+        return getDocumentManagerConfig(List.of(sd));
     }
 
     public static DocumentmanagerConfig.Builder getDocumentManagerConfig(List<String> schemas) {
@@ -38,7 +37,7 @@ public class Deriver {
     }
 
     public static DocumenttypesConfig.Builder getDocumentTypesConfig(String schema) {
-        return getDocumentTypesConfig(Collections.singletonList(schema));
+        return getDocumentTypesConfig(List.of(schema));
     }
 
     public static DocumenttypesConfig.Builder getDocumentTypesConfig(List<String> schemas) {
diff --git a/config-model/src/main/java/com/yahoo/schema/derived/IndexSchema.java b/config-model/src/main/java/com/yahoo/schema/derived/IndexSchema.java
index 34ed9f2f60c..677e4b31bdf 100644
--- a/config-model/src/main/java/com/yahoo/schema/derived/IndexSchema.java
+++ b/config-model/src/main/java/com/yahoo/schema/derived/IndexSchema.java
@@ -14,7 +14,6 @@ import com.yahoo.vespa.config.search.IndexschemaConfig;
 
 import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.LinkedHashMap;
 import java.util.LinkedList;
 import java.util.List;
@@ -147,7 +146,7 @@ public class IndexSchema extends Derived {
     static List<Field> flattenField(Field field) {
         DataType fieldType = field.getDataType();
         if (fieldType.getPrimitiveType() != null){
-            return Collections.singletonList(field);
+            return List.of(field);
         }
         if (fieldType instanceof ArrayDataType) {
             List<Field> ret = new LinkedList<>();