Consistent abstract declaration for utility classes (plus polishing)

Issue: SPR-16968

spring-beans/src/main/java/org/springframework/beans/ExtendedBeanInfo.java

@@ -43,8 +43,10 @@ import org.springframework.util.ObjectUtils;
  * Decorator for a standard {@link BeanInfo} object, e.g. as created by
  * {@link Introspector#getBeanInfo(Class)}, designed to discover and register static
  * and/or non-void returning setter methods. For example:
+ *
  * <pre class="code">
  * public class Bean {
+ *
  *     private Foo foo;
  *
  *     public Foo getFoo() {
@@ -56,6 +58,7 @@ import org.springframework.util.ObjectUtils;
  *         return this;
  *     }
  * }</pre>
+ *
  * The standard JavaBeans {@code Introspector} will discover the {@code getFoo} read
  * method, but will bypass the {@code #setFoo(Foo)} write method, because its non-void
  * returning signature does not comply with the JavaBeans specification.
@@ -68,6 +71,7 @@ import org.springframework.util.ObjectUtils;
  * indexed properties</a> are fully supported.
  *
  * @author Chris Beams
+ * @author Juergen Hoeller
  * @since 3.1
  * @see #ExtendedBeanInfo(BeanInfo)
  * @see ExtendedBeanInfoFactory
@@ -79,8 +83,7 @@ class ExtendedBeanInfo implements BeanInfo {
 
 	private final BeanInfo delegate;
 
-	private final Set<PropertyDescriptor> propertyDescriptors =
-			new TreeSet<>(new PropertyDescriptorComparator());
+	private final Set<PropertyDescriptor> propertyDescriptors = new TreeSet<>(new PropertyDescriptorComparator());
 
 
 	/**
@@ -91,11 +94,9 @@ class ExtendedBeanInfo implements BeanInfo {
 	 * through its method descriptors to find any non-void returning write methods and
 	 * update or create the corresponding {@link PropertyDescriptor} for each one found.
 	 * @param delegate the wrapped {@code BeanInfo}, which is never modified
-	 * @throws IntrospectionException if any problems occur creating and adding new
-	 * property descriptors
 	 * @see #getPropertyDescriptors()
 	 */
-	public ExtendedBeanInfo(BeanInfo delegate) throws IntrospectionException {
+	public ExtendedBeanInfo(BeanInfo delegate) {
 		this.delegate = delegate;
 		for (PropertyDescriptor pd : delegate.getPropertyDescriptors()) {
 			try {
@@ -214,8 +215,8 @@ class ExtendedBeanInfo implements BeanInfo {
 
 	/**
 	 * Return the set of {@link PropertyDescriptor PropertyDescriptors} from the wrapped
-	 * {@link BeanInfo} object as well as {@code PropertyDescriptor BeanInfo} object as well as {@code PropertyDescriptors}
-	 * for each non-void returning setter method found during construction.
+	 * {@link BeanInfo} object as well as {@code PropertyDescriptors} for each non-void
+	 * returning setter method found during construction.
 	 * @see #ExtendedBeanInfo(BeanInfo)
 	 */
 	@Override
@@ -281,7 +282,9 @@ class ExtendedBeanInfo implements BeanInfo {
 			PropertyDescriptorUtils.copyNonMethodProperties(original, this);
 		}
 
-		public SimplePropertyDescriptor(String propertyName, @Nullable Method readMethod, Method writeMethod) throws IntrospectionException {
+		public SimplePropertyDescriptor(String propertyName, @Nullable Method readMethod, Method writeMethod)
+				throws IntrospectionException {
+
 			super(propertyName, null, null);
 			this.readMethod = readMethod;
 			this.writeMethod = writeMethod;
@@ -385,8 +388,9 @@ class ExtendedBeanInfo implements BeanInfo {
 			PropertyDescriptorUtils.copyNonMethodProperties(original, this);
 		}
 
-		public SimpleIndexedPropertyDescriptor(String propertyName, @Nullable Method readMethod, @Nullable Method writeMethod,
-				@Nullable Method indexedReadMethod, Method indexedWriteMethod) throws IntrospectionException {
+		public SimpleIndexedPropertyDescriptor(String propertyName, @Nullable Method readMethod,
+				@Nullable Method writeMethod, @Nullable Method indexedReadMethod, Method indexedWriteMethod)
+				throws IntrospectionException {
 
 			super(propertyName, null, null, null, null);
 			this.readMethod = readMethod;

spring-beans/src/main/java/org/springframework/beans/PropertyDescriptorUtils.java

@@ -30,19 +30,12 @@ import org.springframework.util.ObjectUtils;
  * @author Chris Beams
  * @author Juergen Hoeller
  */
-final class PropertyDescriptorUtils {
-
-
-	private PropertyDescriptorUtils() {
-	}
-
+abstract class PropertyDescriptorUtils {
 
 	/**
 	 * See {@link java.beans.FeatureDescriptor}.
 	 */
-	public static void copyNonMethodProperties(PropertyDescriptor source, PropertyDescriptor target)
-			throws IntrospectionException {
-
+	public static void copyNonMethodProperties(PropertyDescriptor source, PropertyDescriptor target) {
 		target.setExpert(source.isExpert());
 		target.setHidden(source.isHidden());
 		target.setPreferred(source.isPreferred());

spring-beans/src/main/java/org/springframework/beans/factory/support/BeanDefinitionReaderUtils.java

@@ -35,7 +35,7 @@ import org.springframework.util.StringUtils;
  * @see PropertiesBeanDefinitionReader
  * @see org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader
  */
-public final class BeanDefinitionReaderUtils {
+public abstract class BeanDefinitionReaderUtils {
 
 	/**
 	 * Separator for generated bean names. If a class name or parent name is not
@@ -44,10 +44,6 @@ public final class BeanDefinitionReaderUtils {
 	public static final String GENERATED_BEAN_NAME_SEPARATOR = BeanFactoryUtils.GENERATED_BEAN_NAME_SEPARATOR;
 
 
-	private BeanDefinitionReaderUtils() {
-	}
-
-
 	/**
 	 * Create a new GenericBeanDefinition for the given parent name and class name,
 	 * eagerly loading the bean class if a ClassLoader has been specified.

spring-context/src/main/java/org/springframework/cache/config/CacheManagementConfigUtils.java

@@ -22,7 +22,7 @@ package org.springframework.cache.config;
  * @author Juergen Hoeller
  * @since 4.1
  */
-public final class CacheManagementConfigUtils {
+public abstract class CacheManagementConfigUtils {
 
 	/**
 	 * The name of the cache advisor bean.
@@ -48,8 +48,4 @@ public final class CacheManagementConfigUtils {
 	public static final String JCACHE_ASPECT_BEAN_NAME =
 			"org.springframework.cache.config.internalJCacheAspect";
 
-
-	private CacheManagementConfigUtils() {
-	}
-
 }

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

@@ -29,7 +29,6 @@ import org.springframework.core.annotation.AnnotatedElementUtils;
  */
 final class BeanAnnotationHelper {
 
-
 	private BeanAnnotationHelper() {
 	}
 

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

@@ -30,7 +30,6 @@ import org.springframework.beans.factory.support.BeanDefinitionRegistry;
  */
 final class ScopedProxyCreator {
 
-
 	private ScopedProxyCreator() {
 	}
 

spring-context/src/main/java/org/springframework/context/support/PostProcessorRegistrationDelegate.java

@@ -49,7 +49,6 @@ import org.springframework.lang.Nullable;
  */
 final class PostProcessorRegistrationDelegate {
 
-
 	private PostProcessorRegistrationDelegate() {
 	}
 
@@ -306,7 +305,7 @@ final class PostProcessorRegistrationDelegate {
 	 * BeanPostProcessor instantiation, i.e. when a bean is not eligible for
 	 * getting processed by all BeanPostProcessors.
 	 */
-	private static class BeanPostProcessorChecker implements BeanPostProcessor {
+	private static final class BeanPostProcessorChecker implements BeanPostProcessor {
 
 		private static final Log logger = LogFactory.getLog(BeanPostProcessorChecker.class);
 

spring-context/src/main/java/org/springframework/format/datetime/joda/JodaTimeConverters.java

@@ -46,7 +46,6 @@ import org.springframework.format.datetime.DateFormatterRegistrar;
  */
 final class JodaTimeConverters {
 
-
 	private JodaTimeConverters() {
 	}
 

spring-context/src/main/java/org/springframework/format/datetime/standard/DateTimeConverters.java

@@ -43,7 +43,6 @@ import org.springframework.format.datetime.DateFormatterRegistrar;
  */
 final class DateTimeConverters {
 
-
 	private DateTimeConverters() {
 	}
 

spring-context/src/main/java/org/springframework/jmx/support/ObjectNameManager.java

@@ -30,7 +30,6 @@ import javax.management.ObjectName;
  */
 public final class ObjectNameManager {
 
-
 	private ObjectNameManager() {
 	}
 

spring-context/src/main/java/org/springframework/scheduling/config/TaskManagementConfigUtils.java

@@ -22,7 +22,7 @@ package org.springframework.scheduling.config;
  * @author Juergen Hoeller
  * @since 4.1
  */
-public final class TaskManagementConfigUtils {
+public abstract class TaskManagementConfigUtils {
 
 	/**
 	 * The bean name of the internally managed Scheduled annotation processor.
@@ -42,9 +42,4 @@ public final class TaskManagementConfigUtils {
 	public static final String ASYNC_EXECUTION_ASPECT_BEAN_NAME =
 			"org.springframework.scheduling.config.internalAsyncExecutionAspect";
 
-
-	private TaskManagementConfigUtils() {
-	}
-
-
 }

spring-core/src/main/java/org/springframework/core/SpringVersion.java

@@ -25,7 +25,7 @@ import org.springframework.lang.Nullable;
  * <p>Note that some ClassLoaders do not expose the package metadata,
  * hence this class might not be able to determine the Spring version
  * in all environments. Consider using a reflection-based check instead:
- * For example, checking for the presence of a specific Spring 2.0
+ * For example, checking for the presence of a specific Spring 5.0
  * method that you intend to call.
  *
  * @author Juergen Hoeller
@@ -33,7 +33,6 @@ import org.springframework.lang.Nullable;
  */
 public final class SpringVersion {
 
-
 	private SpringVersion() {
 	}
 

spring-core/src/main/java/org/springframework/core/env/ProfilesParser.java

@@ -32,7 +32,11 @@ import org.springframework.util.StringUtils;
  * @author Phillip Webb
  * @since 5.1
  */
-abstract class ProfilesParser {
+final class ProfilesParser {
+
+	private ProfilesParser() {
+	}
+
 
 	static Profiles parse(String... expressions) {
 		Assert.notEmpty(expressions, "Must specify at least one profile");

spring-jdbc/src/main/java/org/springframework/jdbc/config/DatabasePopulatorConfigUtils.java

@@ -38,12 +38,7 @@ import org.springframework.util.xml.DomUtils;
  * @author Stephane Nicoll
  * @since 3.1
  */
-final class DatabasePopulatorConfigUtils {
-
-
-	private DatabasePopulatorConfigUtils() {
-	}
-
+abstract class DatabasePopulatorConfigUtils {
 
 	public static void setDatabasePopulator(Element element, BeanDefinitionBuilder builder) {
 		List<Element> scripts = DomUtils.getChildElementsByTagName(element, "script");

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/embedded/EmbeddedDatabaseConfigurerFactory.java

@@ -29,7 +29,6 @@ import org.springframework.util.Assert;
  */
 final class EmbeddedDatabaseConfigurerFactory {
 
-
 	private EmbeddedDatabaseConfigurerFactory() {
 	}
 

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/embedded/OutputStreamFactory.java

@@ -28,7 +28,6 @@ import java.io.OutputStream;
  */
 public final class OutputStreamFactory {
 
-
 	private OutputStreamFactory() {
 	}
 

spring-test/src/main/java/org/springframework/test/annotation/TestAnnotationUtils.java

@@ -26,12 +26,7 @@ import org.springframework.core.annotation.AnnotatedElementUtils;
  * @author Sam Brannen
  * @since 4.2
  */
-public final class TestAnnotationUtils {
-
-
-	private TestAnnotationUtils() {
-	}
-
+public abstract class TestAnnotationUtils {
 
 	/**
 	 * Get the {@code timeout} configured via the {@link Timed @Timed}

spring-test/src/main/java/org/springframework/test/jdbc/JdbcTestUtils.java

@@ -38,15 +38,11 @@ import org.springframework.util.StringUtils;
  * @see org.springframework.jdbc.datasource.init.ResourceDatabasePopulator
  * @see org.springframework.jdbc.datasource.init.DatabasePopulatorUtils
  */
-public final class JdbcTestUtils {
+public abstract class JdbcTestUtils {
 
 	private static final Log logger = LogFactory.getLog(JdbcTestUtils.class);
 
 
-	private JdbcTestUtils() {
-	}
-
-
 	/**
 	 * Count the rows in the given table.
 	 * @param jdbcTemplate the JdbcTemplate with which to perform JDBC operations

spring-test/src/main/java/org/springframework/test/web/servlet/setup/MockMvcBuilders.java

@@ -35,7 +35,6 @@ import org.springframework.web.context.WebApplicationContext;
  */
 public final class MockMvcBuilders {
 
-
 	private MockMvcBuilders() {
 	}
 

spring-web/src/main/java/org/springframework/web/util/JavaScriptUtils.java

@@ -29,12 +29,7 @@ package org.springframework.web.util;
  * @author Rossen Stoyanchev
  * @since 1.1.1
  */
-public final class JavaScriptUtils {
-
-
-	private JavaScriptUtils() {
-	}
-
+public abstract class JavaScriptUtils {
 
 	/**
 	 * Turn JavaScript special characters into escaped characters.

spring-websocket/src/main/java/org/springframework/web/socket/config/WebSocketNamespaceUtils.java

@@ -44,12 +44,7 @@ import org.springframework.web.socket.sockjs.transport.handler.WebSocketTranspor
  * @author Rossen Stoyanchev
  * @since 4.0
  */
-final class WebSocketNamespaceUtils {
-
-
-	private WebSocketNamespaceUtils() {
-	}
-
+abstract class WebSocketNamespaceUtils {
 
 	public static RuntimeBeanReference registerHandshakeHandler(
 			Element element, ParserContext context, @Nullable Object source) {