Backport of recent ExtendedBeanInfo refinements from 5.1.x

Closes gh-24109

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -41,8 +41,8 @@
 
 /**
  * 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:
+ * {@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 {
@@ -145,11 +145,10 @@ private List<Method> findCandidateWriteMethods(MethodDescriptor[] methodDescript
 
 	public static boolean isCandidateWriteMethod(Method method) {
 		String methodName = method.getName();
-		Class<?>[] parameterTypes = method.getParameterTypes();
-		int nParams = parameterTypes.length;
+		int nParams = method.getParameterCount();
 		return (methodName.length() > 3 && methodName.startsWith("set") && Modifier.isPublic(method.getModifiers()) &&
 				(!void.class.isAssignableFrom(method.getReturnType()) || Modifier.isStatic(method.getModifiers())) &&
-				(nParams == 1 || (nParams == 2 && int.class == parameterTypes[0])));
+				(nParams == 1 || (nParams == 2 && int.class == method.getParameterTypes()[0])));
 	}
 
 	private void handleCandidateWriteMethod(Method method) throws IntrospectionException {
@@ -209,7 +208,7 @@ private PropertyDescriptor findExistingPropertyDescriptor(String propertyName, C
 	}
 
 	private String propertyNameFor(Method method) {
-		return Introspector.decapitalize(method.getName().substring(3, method.getName().length()));
+		return Introspector.decapitalize(method.getName().substring(3));
 	}
 
 
@@ -488,7 +487,7 @@ public void setPropertyEditorClass(@Nullable Class<?> propertyEditorClass) {
 		}
 
 		/*
-		 * See java.beans.IndexedPropertyDescriptor#equals(java.lang.Object)
+		 * See java.beans.IndexedPropertyDescriptor#equals
 		 */
 		@Override
 		public boolean equals(Object other) {
@@ -535,11 +534,13 @@ static class PropertyDescriptorComparator implements Comparator<PropertyDescript
 		public int compare(PropertyDescriptor desc1, PropertyDescriptor desc2) {
 			String left = desc1.getName();
 			String right = desc2.getName();
+			byte[] leftBytes = left.getBytes();
+			byte[] rightBytes = right.getBytes();
 			for (int i = 0; i < left.length(); i++) {
 				if (right.length() == i) {
 					return 1;
 				}
-				int result = left.getBytes()[i] - right.getBytes()[i];
+				int result = leftBytes[i] - rightBytes[i];
 				if (result != 0) {
 					return result;
 				}