Revised indexer implementation

Issue: SPR-11890

spring-context/src/main/java/org/springframework/stereotype/Indexed.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -24,21 +24,21 @@ import java.lang.annotation.Target;
 
 /**
  * Indicate that the annotated element represents a stereotype for the index.
- * <p>
- * The {@code CandidateComponentsIndex} is an alternative to classpath
+ *
+ * <p>The {@code CandidateComponentsIndex} is an alternative to classpath
  * scanning that uses a metadata file generated at compilation time. The
  * index allows retrieving the candidate components (i.e. fully qualified
  * name) based on a stereotype. This annotation instructs the generator to
  * index the element on which the annotated element is present or if it
  * implements or extends from the annotated element. The stereotype is the
  * fully qualified name of the annotated element.
- * <p>
- * Consider the default {@link Component} annotation that is meta-annotated
+ *
+ * <p>Consider the default {@link Component} annotation that is meta-annotated
  * with this annotation. If a component is annotated with {@link Component},
  * an entry for that component will be added to the index using the
  * {@code org.springframework.stereotype.Component} stereotype.
- * <p>
- * This annotation is also honored on meta-annotations. Consider this
+ *
+ * <p>This annotation is also honored on meta-annotations. Consider this
  * custom annotation:
  * <pre class="code">
  * package com.example;
@@ -50,13 +50,15 @@ import java.lang.annotation.Target;
  * &#064;Service
  * public @interface PrivilegedService { ... }
  * </pre>
- * If this annotation is present on an type, it will be indexed with two
+ *
+ * If the above annotation is present on a type, it will be indexed with two
  * stereotypes: {@code org.springframework.stereotype.Component} and
  * {@code com.example.PrivilegedService}. While {@link Service} isn't directly
  * annotated with {@code Indexed}, it is meta-annotated with {@link Component}.
- * <p>
- * It is also possible to index all implementations of a certain interface or
- * all the sub-classes of a given class by adding {@code @Indexed} on it.
+ *
+ * <p>It is also possible to index all implementations of a certain interface or
+ * all the subclasses of a given class by adding {@code @Indexed} on it.
+ *
  * Consider this base interface:
  * <pre class="code">
  * package com.example;
@@ -64,6 +66,7 @@ import java.lang.annotation.Target;
  * &#064;Indexed
  * public interface AdminService { ... }
  * </pre>
+ *
  * Now, consider an implementation of this {@code AdminService} somewhere:
  * <pre class="code">
  * package com.example.foo;
@@ -72,13 +75,14 @@ import java.lang.annotation.Target;
  *
  * public class ConfigurationAdminService implements AdminService { ... }
  * </pre>
+ *
  * Because this class implements an interface that is indexed, it will be
  * automatically included with the {@code com.example.AdminService} stereotype.
- * If there are more {@code @Indexed} interfaces and/or super classes in the
+ * If there are more {@code @Indexed} interfaces and/or superclasses in the
  * hierarchy, the class will map to all their stereotypes.
  *
  * @author Stephane Nicoll
- * @since 4.3.3
+ * @since 5.0
  */
 @Target(ElementType.TYPE)
 @Retention(RetentionPolicy.RUNTIME)

spring-context/src/test/java/org/springframework/context/index/CandidateComponentsIndexLoaderTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2017 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.
@@ -38,6 +38,7 @@ public class CandidateComponentsIndexLoaderTests {
 	@Rule
 	public final ExpectedException thrown = ExpectedException.none();
 
+
 	@Test
 	public void validateIndexIsDisabledByDefault() {
 		CandidateComponentsIndex index = CandidateComponentsIndexLoader.loadIndex(null);
@@ -101,7 +102,7 @@ public class CandidateComponentsIndexLoaderTests {
 	@Test
 	public void loadIndexWithException() throws IOException {
 		final IOException cause = new IOException("test exception");
-		this.thrown.expect(IllegalArgumentException.class);
+		this.thrown.expect(IllegalStateException.class);
 		this.thrown.expectMessage("Unable to load indexes");
 		this.thrown.expectCause(is(cause));
 		CandidateComponentsIndexLoader.loadIndex(new CandidateComponentsTestClassLoader(