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.