Introduce ObjectUtils#nullSafeHash(Object... element)

This commit deprecates the various nullSafeHashCode methods taking array
types as they are superseded by Arrays.hashCode now. This means that
the now only remaining nullSafeHashCode method does not trigger a
warning only if the target type is not an array. At the same time, there
are multiple use of this method on several elements, handling the
accumulation of hash codes.

For that reason, this commit also introduces a nullSafeHash that takes
an array of elements. The only difference between Objects.hash is that
this method handles arrays.

The codebase has been reviewed to use any of those two methods when it
is possible.

Closes gh-29051

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

@@ -90,7 +90,7 @@ public class BeanMetadataAttribute implements BeanMetadataElement {
 
 	@Override
 	public int hashCode() {
-		return this.name.hashCode() * 29 + ObjectUtils.nullSafeHashCode(this.value);
+		return ObjectUtils.nullSafeHash(this.name, this.value);
 	}
 
 	@Override

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

@@ -30,6 +30,7 @@ import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Objects;
 import java.util.Set;
 import java.util.TreeSet;
 
@@ -345,7 +346,7 @@ class ExtendedBeanInfo implements BeanInfo {
 
 		@Override
 		public int hashCode() {
-			return (ObjectUtils.nullSafeHashCode(getReadMethod()) * 29 + ObjectUtils.nullSafeHashCode(getWriteMethod()));
+			return Objects.hash(getReadMethod(), getWriteMethod());
 		}
 
 		@Override
@@ -500,11 +501,8 @@ class ExtendedBeanInfo implements BeanInfo {
 
 		@Override
 		public int hashCode() {
-			int hashCode = ObjectUtils.nullSafeHashCode(getReadMethod());
-			hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(getWriteMethod());
-			hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(getIndexedReadMethod());
-			hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(getIndexedWriteMethod());
-			return hashCode;
+			return Objects.hash(getReadMethod(), getWriteMethod(),
+					getIndexedReadMethod(), getIndexedWriteMethod());
 		}
 
 		@Override

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

@@ -20,6 +20,7 @@ import java.beans.IntrospectionException;
 import java.beans.PropertyDescriptor;
 import java.lang.reflect.Method;
 import java.util.HashSet;
+import java.util.Objects;
 import java.util.Set;
 
 import org.apache.commons.logging.LogFactory;
@@ -30,7 +31,6 @@ import org.springframework.core.MethodParameter;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
-import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
 
 /**
@@ -172,10 +172,7 @@ final class GenericTypeAwarePropertyDescriptor extends PropertyDescriptor {
 
 	@Override
 	public int hashCode() {
-		int hashCode = getBeanClass().hashCode();
-		hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(getReadMethod());
-		hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(getWriteMethod());
-		return hashCode;
+		return Objects.hash(getBeanClass(), getReadMethod(), getWriteMethod());
 	}
 
 }

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

@@ -197,7 +197,7 @@ public class PropertyValue extends BeanMetadataAttributeAccessor implements Seri
 
 	@Override
 	public int hashCode() {
-		return this.name.hashCode() * 29 + ObjectUtils.nullSafeHashCode(this.value);
+		return ObjectUtils.nullSafeHash(this.name, this.value);
 	}
 
 	@Override

spring-beans/src/main/java/org/springframework/beans/factory/InjectionPoint.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -20,6 +20,7 @@ import java.lang.annotation.Annotation;
 import java.lang.reflect.AnnotatedElement;
 import java.lang.reflect.Field;
 import java.lang.reflect.Member;
+import java.util.Objects;
 
 import org.springframework.core.MethodParameter;
 import org.springframework.lang.Nullable;
@@ -190,7 +191,7 @@ public class InjectionPoint {
 
 	@Override
 	public int hashCode() {
-		return (this.field != null ? this.field.hashCode() : ObjectUtils.nullSafeHashCode(this.methodParameter));
+		return Objects.hash(this.field, this.methodParameter);
 	}
 
 	@Override

spring-beans/src/main/java/org/springframework/beans/factory/config/BeanDefinitionHolder.java

@@ -173,10 +173,8 @@ public class BeanDefinitionHolder implements BeanMetadataElement {
 
 	@Override
 	public int hashCode() {
-		int hashCode = this.beanDefinition.hashCode();
-		hashCode = 29 * hashCode + this.beanName.hashCode();
-		hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(this.aliases);
-		return hashCode;
+		return ObjectUtils.nullSafeHash(this.beanDefinition, this.beanName,
+				this.aliases);
 	}
 
 }

spring-beans/src/main/java/org/springframework/beans/factory/config/ConstructorArgumentValues.java

@@ -606,7 +606,7 @@ public class ConstructorArgumentValues {
 		 * same content to reside in the same Set.
 		 */
 		private int contentHashCode() {
-			return ObjectUtils.nullSafeHashCode(this.value) * 29 + ObjectUtils.nullSafeHashCode(this.type);
+			return ObjectUtils.nullSafeHash(this.value, this.type);
 		}
 
 		/**

spring-beans/src/main/java/org/springframework/beans/factory/config/TypedStringValue.java

@@ -223,7 +223,7 @@ public class TypedStringValue implements BeanMetadataElement {
 
 	@Override
 	public int hashCode() {
-		return ObjectUtils.nullSafeHashCode(this.value) * 29 + ObjectUtils.nullSafeHashCode(this.targetType);
+		return ObjectUtils.nullSafeHash(this.value, this.targetType);
 	}
 
 	@Override

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

@@ -113,9 +113,7 @@ public abstract class MethodOverride implements BeanMetadataElement {
 
 	@Override
 	public int hashCode() {
-		int hashCode = ObjectUtils.nullSafeHashCode(this.methodName);
-		hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(this.source);
-		return hashCode;
+		return ObjectUtils.nullSafeHash(this.methodName, this.source);
 	}
 
 }