Next fixes

engine/src/main/java/com/arcadedb/database/DatabaseFactory.java

@@ -120,12 +120,8 @@ public DatabaseFactory setSecurity(final SecurityManager security) {
    * Test only API
    */
   public void registerCallback(final DatabaseInternal.CALLBACK_EVENT event, Callable<Void> callback) {
-    List<Callable<Void>> callbacks = this.callbacks.get(event);
-    if (callbacks == null) {
-      callbacks = new ArrayList<>();
-      this.callbacks.put(event, callbacks);
-    }
-    callbacks.add(callback);
+      List<Callable<Void>> callbacks = this.callbacks.computeIfAbsent(event, k -> new ArrayList<>());
+      callbacks.add(callback);
   }
 
   public static Database getActiveDatabaseInstance(final String databasePath) {

engine/src/main/java/com/arcadedb/query/sql/parser/NestedProjection.java

@@ -161,7 +161,7 @@ private Object apply(Expression expression, Map<String, Object> input, CommandCo
       for (NestedProjectionItem item : includeItems) {
         String alias = item.alias != null ? item.alias.getStringValue() : item.expression.getDefaultAlias().getStringValue();
         ResultInternal elem = new ResultInternal();
-        input.entrySet().forEach(x -> elem.setProperty(x.getKey(), x.getValue()));
+        input.forEach((key, value1) -> elem.setProperty(key, value1));
         Object value = item.expression.execute(elem, ctx);
         if (item.expansion != null) {
           value = item.expand(expression, alias, value, ctx, recursion - 1);

engine/src/main/java/com/arcadedb/schema/DocumentType.java

@@ -688,12 +688,8 @@ public int hashCode() {
   protected void addIndexInternal(final IndexInternal index, final int bucketId, final String[] propertyNames) {
     index.setMetadata(name, propertyNames, bucketId);
 
-    List<IndexInternal> list = bucketIndexesByBucket.get(bucketId);
-    if (list == null) {
-      list = new ArrayList<>();
-      bucketIndexesByBucket.put(bucketId, list);
-    }
-    list.add(index);
+      List<IndexInternal> list = bucketIndexesByBucket.computeIfAbsent(bucketId, k -> new ArrayList<>());
+      list.add(index);
 
     final List<String> propertyList = Arrays.asList(propertyNames);
 

engine/src/main/java/com/arcadedb/utility/TableFormatter.java

@@ -171,12 +171,8 @@ public void setColumnAlignment(final String column, final ALIGNMENT alignment) {
   }
 
   public void setColumnMetadata(final String columnName, final String metadataName, final String metadataValue) {
-    Map<String, String> metadata = columnMetadata.get(columnName);
-    if (metadata == null) {
-      metadata = new LinkedHashMap<String, String>();
-      columnMetadata.put(columnName, metadata);
-    }
-    metadata.put(metadataName, metadataValue);
+      Map<String, String> metadata = columnMetadata.computeIfAbsent(columnName, k -> new LinkedHashMap<String, String>());
+      metadata.put(metadataName, metadataValue);
   }
 
   public int getMaxWidthSize() {

engine/src/test/java/com/arcadedb/index/LSMTreeIndexTest.java

@@ -1060,11 +1060,7 @@ public void run() {
       final Map<Integer, Integer> result = new HashMap<>();
       database.scanType(TYPE_NAME, true, record -> {
         final int id = (int) record.get("id");
-        Integer key = result.get(id);
-        if (key == null)
-          result.put(id, 1);
-        else
-          result.put(id, key + 1);
+          result.merge(id, 1, Integer::sum);
         return true;
       });
 

engine/src/test/java/com/arcadedb/index/TypeLSMTreeIndexTest.java

@@ -761,11 +761,7 @@ public void run() {
       final Map<Integer, Integer> result = new HashMap<>();
       database.scanType(TYPE_NAME, true, record -> {
         final int id = (int) record.get("id");
-        Integer key = result.get(id);
-        if (key == null)
-          result.put(id, 1);
-        else
-          result.put(id, key + 1);
+          result.merge(id, 1, Integer::sum);
         return true;
       });