Polish "Refactor DependencyMetadataV21JsonMapper"

See gh-1628

Author: mhalbritter

initializr-web/src/main/java/io/spring/initializr/web/mapper/DependencyMetadataV21JsonMapper.java

@@ -19,6 +19,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.stream.Collectors;
+
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.JsonNodeFactory;
@@ -28,6 +29,8 @@
 import io.spring.initializr.metadata.DependencyMetadata;
 import io.spring.initializr.metadata.Repository;
 
+import org.springframework.util.CollectionUtils;
+
 /**
  * A {@link DependencyMetadataJsonMapper} handling the metadata format for v2.1.
  *
@@ -76,8 +79,8 @@ private static void addIfNotNull(ObjectNode node, String key, String value) {
 	private static JsonNode mapRepository(Repository repo) {
 		ObjectNode node = nodeFactory.objectNode();
 		node.put("name", repo.getName())
-				.put("url", (repo.getUrl() != null) ? repo.getUrl().toString() : null)
-				.put("snapshotEnabled", repo.isSnapshotsEnabled());
+			.put("url", (repo.getUrl() != null) ? repo.getUrl().toString() : null)
+			.put("snapshotEnabled", repo.isSnapshotsEnabled());
 		return node;
 	}
 
@@ -91,7 +94,7 @@ private static ObjectNode mapBom(BillOfMaterials bom) {
 	}
 
 	private static void addArrayIfNotNull(ObjectNode node, List<String> values) {
-		if (values != null && !values.isEmpty()) {
+		if (!CollectionUtils.isEmpty(values)) {
 			ArrayNode arrayNode = nodeFactory.arrayNode();
 			values.forEach(arrayNode::add);
 			node.set("repositories", arrayNode);
@@ -105,17 +108,21 @@ private static ObjectNode mapNode(Map<String, JsonNode> content) {
 	}
 
 	private ObjectNode mapDependencies(Map<String, Dependency> dependencies) {
-		return mapNode(dependencies.entrySet().stream()
-				.collect(Collectors.toMap(Map.Entry::getKey, entry -> mapDependency(entry.getValue()))));
+		return mapNode(dependencies.entrySet()
+			.stream()
+			.collect(Collectors.toMap(Map.Entry::getKey, (entry) -> mapDependency(entry.getValue()))));
 	}
 
 	private ObjectNode mapRepositories(Map<String, Repository> repositories) {
-		return mapNode(repositories.entrySet().stream()
-				.collect(Collectors.toMap(Map.Entry::getKey, entry -> mapRepository(entry.getValue()))));
+		return mapNode(repositories.entrySet()
+			.stream()
+			.collect(Collectors.toMap(Map.Entry::getKey, (entry) -> mapRepository(entry.getValue()))));
 	}
 
 	private ObjectNode mapBoms(Map<String, BillOfMaterials> boms) {
-		return mapNode(boms.entrySet().stream()
-				.collect(Collectors.toMap(Map.Entry::getKey, entry -> mapBom(entry.getValue()))));
+		return mapNode(boms.entrySet()
+			.stream()
+			.collect(Collectors.toMap(Map.Entry::getKey, (entry) -> mapBom(entry.getValue()))));
 	}
-}
+
+}