DATAJDBC-417 - Polishing.

Reformat code. Fix collection-like node creation to cast to Iterable and consider arrays.

Original pull request: #169.

Author: mp911de

spring-data-relational/src/main/java/org/springframework/data/relational/core/conversion/WritingContext.java

@@ -16,7 +16,7 @@
 package org.springframework.data.relational.core.conversion;
 
 import java.util.ArrayList;
-import java.util.Collection;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
@@ -36,6 +36,7 @@
  *
  * @author Jens Schauder
  * @author Bastian Wilhelm
+ * @author Mark Paluch
  */
 class WritingContext {
 
@@ -116,6 +117,7 @@ private List<DbAction<?>> insertReferenced() {
 		return actions;
 	}
 
+	@SuppressWarnings("unchecked")
 	private List<DbAction<?>> insertAll(PersistentPropertyPath<RelationalPersistentProperty> path) {
 
 		List<DbAction<?>> actions = new ArrayList<>();
@@ -126,7 +128,6 @@ private List<DbAction<?>> insertAll(PersistentPropertyPath<RelationalPersistentP
 			DbAction.Insert<Object> insert;
 			if (node.getPath().getRequiredLeafProperty().isQualified()) {
 
-				@SuppressWarnings("unchecked")
 				Pair<Object, Object> value = (Pair) node.getValue();
 				insert = new DbAction.Insert<>(value.getSecond(), path, parentAction);
 				insert.getQualifiers().put(node.getPath(), value.getFirst());
@@ -240,8 +241,9 @@ private boolean isDirectlyReferencedByRootIgnoringEmbeddables(
 	@Nullable
 	private Object getFromRootValue(PersistentPropertyPath<RelationalPersistentProperty> path) {
 
-		if (path.getLength() == 0)
+		if (path.getLength() == 0) {
 			return entity;
+		}
 
 		Object parent = getFromRootValue(path.getParentPath());
 		if (parent == null) {
@@ -274,7 +276,11 @@ private List<PathNode> createNodes(PersistentPropertyPath<RelationalPersistentPr
 				}
 			}
 		} else if (path.getRequiredLeafProperty().isCollectionLike()) { // collection value
-			((Collection<?>) value).forEach(v -> nodes.add(new PathNode(path, parentNode, v)));
+			if (value.getClass().isArray()) {
+				Arrays.asList((Object[]) value).forEach(v -> nodes.add(new PathNode(path, parentNode, v)));
+			} else {
+				((Iterable<?>) value).forEach(v -> nodes.add(new PathNode(path, parentNode, v)));
+			}
 		} else { // single entity value
 			nodes.add(new PathNode(path, parentNode, value));
 		}

spring-data-relational/src/test/java/org/springframework/data/relational/core/conversion/RelationalEntityWriterUnitTests.java

@@ -117,7 +117,6 @@ public void newEntityGetsConvertedToOneInsertByEmbeddedEntities() {
 				);
 	}
 
-
 	@Test // DATAJDBC-112
 	public void newEntityWithReferenceGetsConvertedToTwoInserts() {
 
@@ -551,6 +550,7 @@ public void savingANullEmbeddedWithEntity() {
 						tuple(InsertRoot.class, EmbeddedReferenceChainEntity.class, "", EmbeddedReferenceChainEntity.class, false) //
 				);
 	}
+
 	@Test // DATAJDBC-417
 	public void savingInnerNullEmbeddedWithEntity() {
 
@@ -570,7 +570,8 @@ public void savingInnerNullEmbeddedWithEntity() {
 						DbActionTestSupport::actualEntityType, //
 						DbActionTestSupport::isWithDependsOn) //
 				.containsExactly( //
-						tuple(InsertRoot.class, RootWithEmbeddedReferenceChainEntity.class, "", RootWithEmbeddedReferenceChainEntity.class, false), //
+						tuple(InsertRoot.class, RootWithEmbeddedReferenceChainEntity.class, "",
+								RootWithEmbeddedReferenceChainEntity.class, false), //
 						tuple(Insert.class, EmbeddedReferenceChainEntity.class, "other", EmbeddedReferenceChainEntity.class, true) //
 				);
 	}
@@ -636,6 +637,7 @@ static class EmbeddedReferenceChainEntity {
 		@Id final Long id;
 		@Embedded(onEmpty = OnEmpty.USE_NULL, prefix = "prefix_") ElementReference other;
 	}
+
 	@RequiredArgsConstructor
 	static class RootWithEmbeddedReferenceChainEntity {