Polishing

spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassParser.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -748,8 +748,7 @@ class ConfigurationClassParser {
 		 * @param importSelector the selector to handle
 		 */
 		public void handle(ConfigurationClass configClass, DeferredImportSelector importSelector) {
-			DeferredImportSelectorHolder holder = new DeferredImportSelectorHolder(
-					configClass, importSelector);
+			DeferredImportSelectorHolder holder = new DeferredImportSelectorHolder(configClass, importSelector);
 			if (this.deferredImportSelectors == null) {
 				DeferredImportSelectorGroupingHandler handler = new DeferredImportSelectorGroupingHandler();
 				handler.register(holder);
@@ -775,7 +774,6 @@ class ConfigurationClassParser {
 				this.deferredImportSelectors = new ArrayList<>();
 			}
 		}
-
 	}
 
 
@@ -786,8 +784,7 @@ class ConfigurationClassParser {
 		private final Map<AnnotationMetadata, ConfigurationClass> configurationClasses = new HashMap<>();
 
 		public void register(DeferredImportSelectorHolder deferredImport) {
-			Class<? extends Group> group = deferredImport.getImportSelector()
-					.getImportGroup();
+			Class<? extends Group> group = deferredImport.getImportSelector().getImportGroup();
 			DeferredImportSelectorGrouping grouping = this.groupings.computeIfAbsent(
 					(group != null ? group : deferredImport),
 					key -> new DeferredImportSelectorGrouping(createGroup(group)));
@@ -799,8 +796,7 @@ class ConfigurationClassParser {
 		public void processGroupImports() {
 			for (DeferredImportSelectorGrouping grouping : this.groupings.values()) {
 				grouping.getImports().forEach(entry -> {
-					ConfigurationClass configurationClass = this.configurationClasses.get(
-							entry.getMetadata());
+					ConfigurationClass configurationClass = this.configurationClasses.get(entry.getMetadata());
 					try {
 						processImports(configurationClass, asSourceClass(configurationClass),
 								asSourceClasses(entry.getImportClassName()), false);
@@ -818,8 +814,7 @@ class ConfigurationClassParser {
 		}
 
 		private Group createGroup(@Nullable Class<? extends Group> type) {
-			Class<? extends Group> effectiveType = (type != null ? type
-					: DefaultDeferredImportSelectorGroup.class);
+			Class<? extends Group> effectiveType = (type != null ? type : DefaultDeferredImportSelectorGroup.class);
 			Group group = BeanUtils.instantiateClass(effectiveType);
 			ParserStrategyUtils.invokeAwareMethods(group,
 					ConfigurationClassParser.this.environment,
@@ -827,7 +822,6 @@ class ConfigurationClassParser {
 					ConfigurationClassParser.this.registry);
 			return group;
 		}
-
 	}
 
 

spring-context/src/main/java/org/springframework/context/annotation/DeferredImportSelector.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -51,6 +51,7 @@ public interface DeferredImportSelector extends ImportSelector {
 
 	/**
 	 * Interface used to group results from different import selectors.
+	 * @since 5.0
 	 */
 	interface Group {
 

spring-context/src/main/java/org/springframework/context/annotation/ImportSelector.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -50,6 +50,7 @@ public interface ImportSelector {
 	/**
 	 * Select and return the names of which class(es) should be imported based on
 	 * the {@link AnnotationMetadata} of the importing @{@link Configuration} class.
+	 * @return the class names, or an empty array if none
 	 */
 	String[] selectImports(AnnotationMetadata importingClassMetadata);
 

spring-context/src/test/java/org/springframework/context/annotation/ImportSelectorTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -530,9 +530,10 @@ public class ImportSelectorTests {
 		static Map<String, List<String>> allImports() {
 			return TestImportGroup.imports.entrySet()
 					.stream()
-					.collect(Collectors.toMap((entry) -> entry.getKey().getClassName(),
+					.collect(Collectors.toMap(entry -> entry.getKey().getClassName(),
 							Map.Entry::getValue));
 		}
+
 		private final List<Entry> instanceImports = new ArrayList<>();
 
 		@Override