From 1de5e52ffde62b5617c1fbcdfa6165baa5ff5224 Mon Sep 17 00:00:00 2001
From: Andrea Cavalli <andrea@cavallium.it>
Date: Sat, 18 Dec 2021 15:15:19 +0100
Subject: [PATCH] Use linkedhashmap

---
 .../database/collections/DatabaseMapDictionary.java        | 3 ++-
 .../dbengine/database/collections/DatabaseStageMap.java    | 7 ++++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/main/java/it/cavallium/dbengine/database/collections/DatabaseMapDictionary.java b/src/main/java/it/cavallium/dbengine/database/collections/DatabaseMapDictionary.java
index c756e17..7f67ea8 100644
--- a/src/main/java/it/cavallium/dbengine/database/collections/DatabaseMapDictionary.java
+++ b/src/main/java/it/cavallium/dbengine/database/collections/DatabaseMapDictionary.java
@@ -19,6 +19,7 @@ import it.cavallium.dbengine.database.serialization.Serializer;
 import it.cavallium.dbengine.database.serialization.SerializerFixedBinaryLength;
 import java.util.Collections;
 import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -150,7 +151,7 @@ public class DatabaseMapDictionary<T, U> extends DatabaseMapDictionaryDeep<T, U,
 						sink.error(ex);
 					}
 				})
-				.collectMap(Entry::getKey, Entry::getValue, HashMap::new)
+				.collectMap(Entry::getKey, Entry::getValue, LinkedHashMap::new)
 				.filter(map -> !map.isEmpty());
 	}
 
diff --git a/src/main/java/it/cavallium/dbengine/database/collections/DatabaseStageMap.java b/src/main/java/it/cavallium/dbengine/database/collections/DatabaseStageMap.java
index 089cf69..47a6318 100644
--- a/src/main/java/it/cavallium/dbengine/database/collections/DatabaseStageMap.java
+++ b/src/main/java/it/cavallium/dbengine/database/collections/DatabaseStageMap.java
@@ -10,6 +10,7 @@ import it.cavallium.dbengine.database.serialization.KVSerializationFunction;
 import it.cavallium.dbengine.database.serialization.SerializationException;
 import it.cavallium.dbengine.database.serialization.SerializationFunction;
 import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Objects;
@@ -187,7 +188,7 @@ public interface DatabaseStageMap<T, U, US extends DatabaseStage<U>> extends Dat
 	default Mono<Map<T, U>> setAndGetPrevious(Map<T, U> value) {
 		return this
 				.setAllValuesAndGetPrevious(Flux.fromIterable(Map.copyOf(value).entrySet()))
-				.collectMap(Entry::getKey, Entry::getValue, HashMap::new)
+				.collectMap(Entry::getKey, Entry::getValue, LinkedHashMap::new)
 				.filter(map -> !map.isEmpty());
 	}
 
@@ -209,7 +210,7 @@ public interface DatabaseStageMap<T, U, US extends DatabaseStage<U>> extends Dat
 					if (updateMode == UpdateMode.ALLOW_UNSAFE) {
 						return this
 								.getAllValues(null)
-								.collectMap(Entry::getKey, Entry::getValue, HashMap::new)
+								.collectMap(Entry::getKey, Entry::getValue, LinkedHashMap::new)
 								.single()
 								.<Tuple2<Optional<Map<T, U>>, Optional<Map<T, U>>>>handle((v, sink) -> {
 									if (v.isEmpty()) {
@@ -255,7 +256,7 @@ public interface DatabaseStageMap<T, U, US extends DatabaseStage<U>> extends Dat
 	default Mono<Map<T, U>> get(@Nullable CompositeSnapshot snapshot, boolean existsAlmostCertainly) {
 		return this
 				.getAllValues(snapshot)
-				.collectMap(Entry::getKey, Entry::getValue, HashMap::new)
+				.collectMap(Entry::getKey, Entry::getValue, LinkedHashMap::new)
 				.filter(map -> !map.isEmpty());
 	}