Migrate to JSpecify annotations for nullability constraints.

Closes #3170

src/main/java/org/springframework/data/annotation/AccessType.java

@@ -28,7 +28,7 @@ import java.lang.annotation.Target;
  * @author Oliver Gierke
  */
 @Documented
-@Target({ ElementType.ANNOTATION_TYPE, ElementType.TYPE, ElementType.FIELD, ElementType.METHOD, })
+@Target({ ElementType.ANNOTATION_TYPE, ElementType.TYPE, ElementType.FIELD, ElementType.METHOD })
 @Retention(RetentionPolicy.RUNTIME)
 public @interface AccessType {
 
@@ -40,4 +40,5 @@ public @interface AccessType {
 	enum Type {
 		FIELD, PROPERTY;
 	}
+
 }

src/main/java/org/springframework/data/annotation/package-info.java

@@ -1,5 +1,5 @@
 /**
  * Core annotations being used by Spring Data.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.annotation;

src/main/java/org/springframework/data/aot/AotContext.java

@@ -22,6 +22,8 @@ import java.util.Optional;
 import java.util.Set;
 import java.util.function.Consumer;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.config.BeanDefinition;
@@ -29,7 +31,6 @@ import org.springframework.beans.factory.config.BeanReference;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.beans.factory.support.RootBeanDefinition;
 import org.springframework.data.util.TypeScanner;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**

src/main/java/org/springframework/data/aot/AuditingBeanRegistrationAotProcessor.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.aot;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.aop.SpringProxy;
 import org.springframework.aop.framework.Advised;
 import org.springframework.aot.hint.RuntimeHints;
@@ -26,7 +28,6 @@ import org.springframework.core.DecoratingProxy;
 import org.springframework.data.domain.AuditorAware;
 import org.springframework.data.domain.ReactiveAuditorAware;
 import org.springframework.data.util.ReactiveWrappers;
-import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 
 /**

src/main/java/org/springframework/data/aot/DefaultAotContext.java

@@ -20,6 +20,8 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.NoSuchBeanDefinitionException;
 import org.springframework.beans.factory.config.BeanDefinition;
@@ -132,7 +134,7 @@ class DefaultAotContext implements AotContext {
 		}
 
 		@Override
-		public Class<?> resolveType() {
+		public @Nullable Class<?> resolveType() {
 			return factory.getType(beanName, false);
 		}
 	}

src/main/java/org/springframework/data/aot/ManagedTypesBeanFactoryInitializationAotProcessor.java

@@ -20,6 +20,7 @@ import java.util.function.Supplier;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.beans.factory.aot.BeanFactoryInitializationAotContribution;
 import org.springframework.beans.factory.aot.BeanFactoryInitializationAotProcessor;
@@ -30,7 +31,6 @@ import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.data.domain.ManagedTypes;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.ObjectUtils;
 
@@ -48,9 +48,9 @@ public class ManagedTypesBeanFactoryInitializationAotProcessor implements BeanFa
 	private static final Log logger = LogFactory.getLog(ManagedTypesBeanFactoryInitializationAotProcessor.class);
 
 	@Override
-	@Nullable
 	@Contract("_ -> null")
-	public BeanFactoryInitializationAotContribution processAheadOfTime(ConfigurableListableBeanFactory beanFactory) {
+	public @Nullable BeanFactoryInitializationAotContribution processAheadOfTime(
+			ConfigurableListableBeanFactory beanFactory) {
 
 		processManagedTypes(beanFactory);
 		return null;
@@ -82,12 +82,15 @@ public class ManagedTypesBeanFactoryInitializationAotProcessor implements BeanFa
 				}
 
 				Object value = potentiallyWrapToIterable(supplier.get());
+				String beanClassName = beanDefinition.getBeanClassName();
 
-				BeanDefinition beanDefinitionReplacement = newManagedTypeBeanDefinition(beanDefinition.getBeanClassName(),
-						value);
+				if (beanClassName != null) {
 
-				registry.removeBeanDefinition(beanName);
-				registry.registerBeanDefinition(beanName, beanDefinitionReplacement);
+					BeanDefinition beanDefinitionReplacement = newManagedTypeBeanDefinition(beanClassName, value);
+
+					registry.removeBeanDefinition(beanName);
+					registry.registerBeanDefinition(beanName, beanDefinitionReplacement);
+				}
 			}
 		}
 	}

src/main/java/org/springframework/data/aot/ManagedTypesBeanRegistrationAotProcessor.java

@@ -21,6 +21,8 @@ import java.util.Set;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.aot.generate.GenerationContext;
 import org.springframework.beans.factory.BeanCreationException;
 import org.springframework.beans.factory.BeanFactory;
@@ -34,7 +36,6 @@ import org.springframework.data.domain.ManagedTypes;
 import org.springframework.data.util.QTypeContributor;
 import org.springframework.data.util.TypeContributor;
 import org.springframework.data.util.TypeUtils;
-import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
 
@@ -61,7 +62,7 @@ public class ManagedTypesBeanRegistrationAotProcessor implements BeanRegistratio
 	}
 
 	@Override
-	public BeanRegistrationAotContribution processAheadOfTime(RegisteredBean registeredBean) {
+	public @Nullable BeanRegistrationAotContribution processAheadOfTime(RegisteredBean registeredBean) {
 
 		if (!isMatch(registeredBean.getBeanClass(), registeredBean.getBeanName())) {
 			return null;

src/main/java/org/springframework/data/aot/ManagedTypesRegistrationAotContribution.java

@@ -22,6 +22,8 @@ import java.util.function.BiConsumer;
 
 import javax.lang.model.element.Modifier;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.aot.generate.AccessControl;
 import org.springframework.aot.generate.GeneratedMethod;
 import org.springframework.aot.generate.GenerationContext;
@@ -41,7 +43,6 @@ import org.springframework.javapoet.MethodSpec.Builder;
 import org.springframework.javapoet.ParameterizedTypeName;
 import org.springframework.javapoet.TypeName;
 import org.springframework.javapoet.WildcardTypeName;
-import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.ReflectionUtils;

src/main/java/org/springframework/data/aot/package-info.java

@@ -2,5 +2,5 @@
  * Support for registering the need for reflection, resources, java serialization and proxies at runtime for Ahead of
  * Time compilation.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.aot;

src/main/java/org/springframework/data/auditing/AuditableBeanWrapper.java

@@ -18,8 +18,9 @@ package org.springframework.data.auditing;
 import java.time.temporal.TemporalAccessor;
 import java.util.Optional;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 
 /**
  * Interface to abstract the ways setting the auditing information can be implemented.

src/main/java/org/springframework/data/auditing/AuditingHandlerSupport.java

@@ -20,11 +20,11 @@ import java.util.Optional;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.core.log.LogMessage;
 import org.springframework.data.domain.Auditable;
 import org.springframework.data.mapping.context.PersistentEntities;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**

src/main/java/org/springframework/data/auditing/Auditor.java

@@ -17,7 +17,8 @@ package org.springframework.data.auditing;
 
 import java.util.Optional;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.ObjectUtils;
 
 /**

src/main/java/org/springframework/data/auditing/DefaultAuditableBeanWrapperFactory.java

@@ -24,13 +24,14 @@ import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.stream.Stream;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.ResolvableType;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.data.convert.Jsr310Converters;
 import org.springframework.data.domain.Auditable;
 import org.springframework.data.util.ReflectionUtils;
 import org.springframework.format.support.DefaultFormattingConversionService;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -115,7 +116,7 @@ class DefaultAuditableBeanWrapperFactory implements AuditableBeanWrapperFactory
 		}
 
 		@Override
-		public Object setCreatedBy(@Nullable Object value) {
+		public @Nullable Object setCreatedBy(@Nullable Object value) {
 
 			auditable.setCreatedBy(value);
 			return value;
@@ -130,7 +131,7 @@ class DefaultAuditableBeanWrapperFactory implements AuditableBeanWrapperFactory
 		}
 
 		@Override
-		public Object setLastModifiedBy(Object value) {
+		public @Nullable Object setLastModifiedBy(@Nullable Object value) {
 
 			auditable.setLastModifiedBy(value);
 
@@ -267,7 +268,7 @@ class DefaultAuditableBeanWrapperFactory implements AuditableBeanWrapperFactory
 		}
 
 		@Override
-		public Object setCreatedBy(@Nullable Object value) {
+		public @Nullable Object setCreatedBy(@Nullable Object value) {
 			return setField(metadata.getCreatedByField(), value);
 		}
 
@@ -277,7 +278,7 @@ class DefaultAuditableBeanWrapperFactory implements AuditableBeanWrapperFactory
 		}
 
 		@Override
-		public Object setLastModifiedBy(@Nullable Object value) {
+		public @Nullable Object setLastModifiedBy(@Nullable Object value) {
 			return setField(metadata.getLastModifiedByField(), value);
 		}
 

src/main/java/org/springframework/data/auditing/MappingAuditableBeanWrapperFactory.java

@@ -23,6 +23,8 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Predicate;
 import java.util.stream.Stream;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.ConversionService;
 import org.springframework.data.annotation.CreatedBy;
 import org.springframework.data.annotation.CreatedDate;
@@ -41,7 +43,6 @@ import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.mapping.context.PersistentEntities;
 import org.springframework.data.util.Lazy;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -195,7 +196,7 @@ public class MappingAuditableBeanWrapperFactory extends DefaultAuditableBeanWrap
 		}
 
 		@Override
-		public Object setCreatedBy(Object value) {
+		public @Nullable Object setCreatedBy(@Nullable Object value) {
 			return setProperty(metadata.createdByPaths, value);
 		}
 
@@ -205,7 +206,7 @@ public class MappingAuditableBeanWrapperFactory extends DefaultAuditableBeanWrap
 		}
 
 		@Override
-		public Object setLastModifiedBy(@Nullable Object value) {
+		public @Nullable Object setLastModifiedBy(@Nullable Object value) {
 			return setProperty(metadata.lastModifiedByPaths, value);
 		}
 

src/main/java/org/springframework/data/auditing/config/AuditingHandlerBeanDefinitionParser.java

@@ -17,6 +17,8 @@ package org.springframework.data.auditing.config;
 
 import static org.springframework.beans.factory.support.BeanDefinitionBuilder.*;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.aop.framework.ProxyFactoryBean;
 import org.springframework.aop.target.LazyInitTargetSource;
 import org.springframework.beans.factory.config.BeanDefinition;
@@ -45,7 +47,7 @@ public class AuditingHandlerBeanDefinitionParser extends AbstractSingleBeanDefin
 	private static final String AUDITOR_AWARE_REF = "auditor-aware-ref";
 
 	private final String mappingContextBeanName;
-	private String resolvedBeanName;
+	private @Nullable String resolvedBeanName;
 
 	/**
 	 * Creates a new {@link AuditingHandlerBeanDefinitionParser} to point to a {@link MappingContext} with the given bean
@@ -65,7 +67,7 @@ public class AuditingHandlerBeanDefinitionParser extends AbstractSingleBeanDefin
 	 *
 	 * @return the resolvedBeanName
 	 */
-	public String getResolvedBeanName() {
+	public @Nullable String getResolvedBeanName() {
 		return resolvedBeanName;
 	}
 

src/main/java/org/springframework/data/auditing/config/package-info.java

@@ -1,5 +1,5 @@
 /**
  * Types to abstract authentication concepts.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.auditing.config;

src/main/java/org/springframework/data/auditing/package-info.java

@@ -1,5 +1,5 @@
 /**
  * General support for entity auditing.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.auditing;

src/main/java/org/springframework/data/config/ParsingUtils.java

@@ -15,15 +15,17 @@
  */
 package org.springframework.data.config;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.config.BeanDefinition;
 import org.springframework.beans.factory.config.ObjectFactoryCreatingFactoryBean;
 import org.springframework.beans.factory.support.AbstractBeanDefinition;
 import org.springframework.beans.factory.support.BeanDefinitionBuilder;
 import org.springframework.beans.factory.xml.BeanDefinitionParser;
 import org.springframework.beans.factory.xml.ParserContext;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
+
 import org.w3c.dom.Element;
 
 /**

src/main/java/org/springframework/data/config/TypeFilterParser.java

@@ -20,6 +20,8 @@ import java.util.Collection;
 import java.util.HashSet;
 import java.util.regex.Pattern;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.BeanUtils;
 import org.springframework.beans.FatalBeanException;
 import org.springframework.beans.factory.parsing.ReaderContext;
@@ -30,7 +32,6 @@ import org.springframework.core.type.filter.AspectJTypeFilter;
 import org.springframework.core.type.filter.AssignableTypeFilter;
 import org.springframework.core.type.filter.RegexPatternTypeFilter;
 import org.springframework.core.type.filter.TypeFilter;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 import org.w3c.dom.Element;
@@ -101,7 +102,8 @@ public class TypeFilterParser {
 			try {
 				filters.add(createTypeFilter(childElement, classLoader));
 			} catch (RuntimeException e) {
-				readerContext.error(e.getMessage(), readerContext.extractSource(element), e.getCause());
+				readerContext.error("Failed creating type filter: " + e.getMessage(), readerContext.extractSource(element),
+						e.getCause());
 			}
 		}
 

src/main/java/org/springframework/data/config/package-info.java

@@ -1,5 +1,5 @@
 /**
  * Basic support for creating custom Spring namespaces and JavaConfig.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.config;

src/main/java/org/springframework/data/convert/AnnotatedPropertyValueConverterAccessor.java

@@ -15,8 +15,9 @@
  */
 package org.springframework.data.convert;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.PersistentProperty;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -28,7 +29,7 @@ import org.springframework.util.Assert;
 class AnnotatedPropertyValueConverterAccessor {
 
 	private final String name;
-	private final ValueConverter annotation;
+	private final @Nullable ValueConverter annotation;
 
 	public AnnotatedPropertyValueConverterAccessor(PersistentProperty<?> property) {
 
@@ -45,9 +46,8 @@ class AnnotatedPropertyValueConverterAccessor {
 	 * @return {@literal null} if none defined. Check {@link #hasValueConverter()} to check if the annotation is present
 	 *         at all.
 	 */
-	@Nullable
 	@SuppressWarnings({ "unchecked", "rawtypes" })
-	public Class<? extends PropertyValueConverter<?, ?, ? extends ValueConversionContext<? extends PersistentProperty<?>>>> getValueConverterType() {
+	public @Nullable Class<? extends PropertyValueConverter<?, ?, ? extends ValueConversionContext<? extends PersistentProperty<?>>>> getValueConverterType() {
 		return annotation != null ? (Class) annotation.value() : null;
 	}
 

src/main/java/org/springframework/data/convert/ConfigurableTypeInformationMapper.java

@@ -19,11 +19,12 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Map.Entry;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.Alias;
 import org.springframework.data.mapping.PersistentEntity;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -71,9 +72,8 @@ public class ConfigurableTypeInformationMapper implements TypeInformationMapper
 		return typeToAlias.getOrDefault(type, Alias.NONE);
 	}
 
-	@Nullable
 	@Override
-	public TypeInformation<?> resolveTypeFrom(Alias alias) {
+	public @Nullable TypeInformation<?> resolveTypeFrom(Alias alias) {
 		return aliasToType.get(alias);
 	}
 }

src/main/java/org/springframework/data/convert/CustomConversions.java

@@ -23,6 +23,7 @@ import java.util.stream.Collectors;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.jspecify.annotations.Nullable;
 
 import org.springframework.core.GenericTypeResolver;
 import org.springframework.core.annotation.AnnotationUtils;
@@ -38,7 +39,6 @@ import org.springframework.data.mapping.model.SimpleTypeHolder;
 import org.springframework.data.util.CustomCollections;
 import org.springframework.data.util.Predicates;
 import org.springframework.data.util.Streamable;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
@@ -249,8 +249,7 @@ public class CustomConversions {
 	 *         data store does not support property value conversions.
 	 * @see PropertyValueConversions
 	 */
-	@Nullable
-	public PropertyValueConversions getPropertyValueConversions() {
+	public @Nullable PropertyValueConversions getPropertyValueConversions() {
 		return propertyValueConversions;
 	}
 
@@ -447,8 +446,7 @@ public class CustomConversions {
 	 * @param targetType must not be {@literal null}.
 	 * @return the actual target type for the given {@code sourceType} and {@code targetType}.
 	 */
-	@Nullable
-	private Class<?> getCustomReadTarget(Class<?> sourceType, Class<?> targetType) {
+	private @Nullable Class<?> getCustomReadTarget(Class<?> sourceType, Class<?> targetType) {
 		return customReadTargetTypes.computeIfAbsent(sourceType, targetType, getReadTarget);
 	}
 
@@ -461,8 +459,7 @@ public class CustomConversions {
 	 * @param pairs must not be {@literal null}.
 	 * @return the base {@link Class type} for the (requested) {@link Class target type} if present.
 	 */
-	@Nullable
-	private Class<?> getCustomTarget(Class<?> sourceType, @Nullable Class<?> targetType,
+	private @Nullable Class<?> getCustomTarget(Class<?> sourceType, @Nullable Class<?> targetType,
 			Collection<ConvertiblePair> pairs) {
 
 		if (targetType != null && pairs.contains(new ConvertiblePair(sourceType, targetType))) {
@@ -505,8 +502,8 @@ public class CustomConversions {
 		 * @param mappingFunction must not be {@literal null}.
 		 * @return the optional target type.
 		 */
-		@Nullable
-		public Class<?> computeIfAbsent(Class<?> sourceType, Function<ConvertiblePair, Class<?>> mappingFunction) {
+		public @Nullable Class<?> computeIfAbsent(Class<?> sourceType,
+				Function<ConvertiblePair, Class<?>> mappingFunction) {
 			return computeIfAbsent(sourceType, AbsentTargetTypeMarker.class, mappingFunction);
 		}
 
@@ -520,8 +517,7 @@ public class CustomConversions {
 		 * @param mappingFunction must not be {@literal null}.
 		 * @return the optional target type.
 		 */
-		@Nullable
-		public Class<?> computeIfAbsent(Class<?> sourceType, Class<?> targetType,
+		public @Nullable Class<?> computeIfAbsent(Class<?> sourceType, Class<?> targetType,
 				Function<ConvertiblePair, Class<?>> mappingFunction) {
 
 			TargetTypes targetTypes = customReadTargetTypes.get(sourceType);
@@ -575,8 +571,8 @@ public class CustomConversions {
 		 * @param mappingFunction must not be {@literal null}.
 		 * @return the optional target type.
 		 */
-		@Nullable
-		public Class<?> computeIfAbsent(Class<?> targetType, Function<ConvertiblePair, Class<?>> mappingFunction) {
+		public @Nullable Class<?> computeIfAbsent(Class<?> targetType,
+				Function<ConvertiblePair, Class<?>> mappingFunction) {
 
 			Class<?> optionalTarget = conversionTargets.get(targetType);
 
@@ -927,7 +923,7 @@ public class CustomConversions {
 		private final StoreConversions storeConversions;
 		private final List<?> userConverters;
 		private final Predicate<ConvertiblePair> converterRegistrationFilter;
-		private final PropertyValueConversions propertyValueConversions;
+		private final @Nullable PropertyValueConversions propertyValueConversions;
 
 		/**
 		 * Create a new ConverterConfiguration holding the given {@link StoreConversions} and user defined converters.
@@ -1004,8 +1000,7 @@ public class CustomConversions {
 		 * @return the configured {@link PropertyValueConversions} if set, {@literal null} otherwise.
 		 * @since 2.7
 		 */
-		@Nullable
-		public PropertyValueConversions getPropertyValueConversions() {
+		public @Nullable PropertyValueConversions getPropertyValueConversions() {
 			return this.propertyValueConversions;
 		}
 	}

src/main/java/org/springframework/data/convert/DefaultConverterBuilder.java

@@ -21,6 +21,8 @@ import java.util.Set;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.TypeDescriptor;
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.core.convert.converter.GenericConverter;
@@ -29,7 +31,6 @@ import org.springframework.data.convert.ConverterBuilder.ConverterAware;
 import org.springframework.data.convert.ConverterBuilder.ReadingConverterBuilder;
 import org.springframework.data.convert.ConverterBuilder.WritingConverterBuilder;
 import org.springframework.data.util.Optionals;
-import org.springframework.lang.Nullable;
 import org.springframework.util.ObjectUtils;
 
 /**
@@ -111,10 +112,9 @@ record DefaultConverterBuilder<S, T> (ConvertiblePair convertiblePair,
 			this.function = function;
 		}
 
-		@Nullable
 		@Override
 		@SuppressWarnings("unchecked")
-		public Object convert(@Nullable Object source, TypeDescriptor sourceType, TypeDescriptor targetType) {
+		public @Nullable Object convert(@Nullable Object source, TypeDescriptor sourceType, TypeDescriptor targetType) {
 			return function.apply((S) source);
 		}
 

src/main/java/org/springframework/data/convert/DefaultTypeMapper.java

@@ -23,12 +23,13 @@ import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.Function;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.BeanClassLoaderAware;
 import org.springframework.data.mapping.Alias;
 import org.springframework.data.mapping.PersistentEntity;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -106,9 +107,8 @@ public class DefaultTypeMapper<S> implements TypeMapper<S>, BeanClassLoaderAware
 		};
 	}
 
-	@Nullable
 	@Override
-	public TypeInformation<?> readType(S source) {
+	public @Nullable TypeInformation<?> readType(S source) {
 
 		Assert.notNull(source, "Source object must not be null");
 
@@ -122,8 +122,7 @@ public class DefaultTypeMapper<S> implements TypeMapper<S>, BeanClassLoaderAware
 	 * @param alias
 	 * @return
 	 */
-	@Nullable
-	private TypeInformation<?> getFromCacheOrCreate(Alias alias) {
+	private @Nullable TypeInformation<?> getFromCacheOrCreate(Alias alias) {
 		return typeCache.computeIfAbsent(alias, getAlias).orElse(null);
 	}
 
@@ -160,8 +159,7 @@ public class DefaultTypeMapper<S> implements TypeMapper<S>, BeanClassLoaderAware
 	 * @param source
 	 * @return
 	 */
-	@Nullable
-	private Class<?> getDefaultedTypeToBeUsed(S source) {
+	private @Nullable Class<?> getDefaultedTypeToBeUsed(S source) {
 
 		TypeInformation<?> type = readType(source);
 		type = type == null ? getFallbackTypeFor(source) : type;
@@ -174,8 +172,7 @@ public class DefaultTypeMapper<S> implements TypeMapper<S>, BeanClassLoaderAware
 	 * @param source will never be {@literal null}.
 	 * @return
 	 */
-	@Nullable
-	protected TypeInformation<?> getFallbackTypeFor(S source) {
+	protected @Nullable TypeInformation<?> getFallbackTypeFor(S source) {
 		return null;
 	}
 

src/main/java/org/springframework/data/convert/DtoInstantiatingConverter.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.convert;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.mapping.InstanceCreatorMetadata;
 import org.springframework.data.mapping.Parameter;
@@ -28,7 +30,6 @@ import org.springframework.data.mapping.model.EntityInstantiator;
 import org.springframework.data.mapping.model.EntityInstantiators;
 import org.springframework.data.mapping.model.ParameterValueProvider;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -81,9 +82,8 @@ public class DtoInstantiatingConverter implements Converter<Object, Object> {
 		Object dto = instantiator.createInstance(targetEntity, new ParameterValueProvider() {
 
 			@Override
-			@Nullable
 			@SuppressWarnings({ "rawtypes" })
-			public Object getParameterValue(Parameter parameter) {
+			public @Nullable Object getParameterValue(Parameter parameter) {
 
 				String name = parameter.getName();
 

src/main/java/org/springframework/data/convert/Jsr310Converters.java

@@ -33,8 +33,9 @@ import java.util.Collections;
 import java.util.Date;
 import java.util.List;
 
+import org.jspecify.annotations.NonNull;
+
 import org.springframework.core.convert.converter.Converter;
-import org.springframework.lang.NonNull;
 
 /**
  * Helper class to register JSR-310 specific {@link Converter} implementations.

src/main/java/org/springframework/data/convert/MappingContextTypeInformationMapper.java

@@ -18,12 +18,13 @@ package org.springframework.data.convert;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.Alias;
 import org.springframework.data.mapping.PersistentEntity;
 import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -109,9 +110,8 @@ public class MappingContextTypeInformationMapper implements TypeInformationMappe
 		return alias;
 	}
 
-	@Nullable
 	@Override
-	public TypeInformation<?> resolveTypeFrom(Alias alias) {
+	public @Nullable TypeInformation<?> resolveTypeFrom(Alias alias) {
 
 		for (Map.Entry<TypeInformation<?>, Alias> entry : typeMap.entrySet()) {
 			if (entry.getValue().hasSamePresentValueAs(alias)) {

src/main/java/org/springframework/data/convert/PropertyValueConversionService.java

@@ -15,8 +15,9 @@
  */
 package org.springframework.data.convert;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.PersistentProperty;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -74,8 +75,8 @@ public class PropertyValueConversionService {
 	 * @param <VCC> value conversion context type.
 	 * @return the value to be used in the domain model. Can be {@code null}.
 	 */
-	@Nullable
-	public <P extends PersistentProperty<P>, VCC extends ValueConversionContext<P>> Object read(@Nullable Object value,
+	public <P extends PersistentProperty<P>, VCC extends ValueConversionContext<P>> @Nullable Object read(
+			@Nullable Object value,
 			P property, VCC context) {
 
 		PropertyValueConverter<Object, Object, ValueConversionContext<P>> converter = conversions
@@ -95,8 +96,8 @@ public class PropertyValueConversionService {
 	 * @param <VCC> value conversion context type.
 	 * @return the value to be written to the data store. Can be {@code null}.
 	 */
-	@Nullable
-	public <P extends PersistentProperty<P>, VCC extends ValueConversionContext<P>> Object write(@Nullable Object value,
+	public <P extends PersistentProperty<P>, VCC extends ValueConversionContext<P>> @Nullable Object write(
+			@Nullable Object value,
 			P property, VCC context) {
 
 		PropertyValueConverter<Object, Object, ValueConversionContext<P>> converter = conversions

src/main/java/org/springframework/data/convert/PropertyValueConverter.java

@@ -17,8 +17,9 @@ package org.springframework.data.convert;
 
 import java.util.function.BiFunction;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.PersistentProperty;
-import org.springframework.lang.Nullable;
 
 /**
  * {@link PropertyValueConverter} provides a symmetric way of converting certain properties from domain to
@@ -87,8 +88,7 @@ public interface PropertyValueConverter<DV, SV, C extends ValueConversionContext
 	 *          never {@literal null}.
 	 * @return the converted value. Can be {@literal null}.
 	 */
-	@Nullable
-	default SV writeNull(C context) {
+	default @Nullable SV writeNull(C context) {
 		return null;
 	}
 
@@ -102,15 +102,13 @@ public interface PropertyValueConverter<DV, SV, C extends ValueConversionContext
 
 		INSTANCE;
 
-		@Nullable
 		@Override
-		public Object read(@Nullable Object value, ValueConversionContext context) {
+		public @Nullable Object read(@Nullable Object value, ValueConversionContext context) {
 			return value;
 		}
 
-		@Nullable
 		@Override
-		public Object write(@Nullable Object value, ValueConversionContext context) {
+		public @Nullable Object write(@Nullable Object value, ValueConversionContext context) {
 			return value;
 		}
 	}
@@ -133,25 +131,23 @@ public interface PropertyValueConverter<DV, SV, C extends ValueConversionContext
 			this.reader = reader;
 		}
 
-		@Nullable
 		@Override
-		public SV write(@Nullable DV value, ValueConversionContext<P> context) {
+		public @Nullable SV write(@Nullable DV value, ValueConversionContext<P> context) {
 			return writer.apply(value, context);
 		}
 
 		@Override
-		public SV writeNull(ValueConversionContext<P> context) {
+		public @Nullable SV writeNull(ValueConversionContext<P> context) {
 			return writer.apply(null, context);
 		}
 
-		@Nullable
 		@Override
-		public DV read(@Nullable SV value, ValueConversionContext<P> context) {
+		public @Nullable DV read(@Nullable SV value, ValueConversionContext<P> context) {
 			return reader.apply(value, context);
 		}
 
 		@Override
-		public DV readNull(ValueConversionContext<P> context) {
+		public @Nullable DV readNull(ValueConversionContext<P> context) {
 			return reader.apply(null, context);
 		}
 	}

src/main/java/org/springframework/data/convert/PropertyValueConverterFactories.java

@@ -23,12 +23,13 @@ import java.util.Objects;
 import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
 import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -57,10 +58,9 @@ final class PropertyValueConverterFactories {
 			this.delegates = Collections.unmodifiableList(delegates);
 		}
 
-		@Nullable
 		@Override
 		@SuppressWarnings("unchecked")
-		public <A, B, C extends ValueConversionContext<?>> PropertyValueConverter<A, B, C> getConverter(
+		public <A, B, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<A, B, C> getConverter(
 				PersistentProperty<?> property) {
 
 			return delegates.stream().map(it -> (PropertyValueConverter<A, B, C>) it.getConverter(property))
@@ -68,7 +68,7 @@ final class PropertyValueConverterFactories {
 		}
 
 		@Override
-		public <S, T, C extends ValueConversionContext<?>> PropertyValueConverter<S, T, C> getConverter(
+		public <S, T, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<S, T, C> getConverter(
 				Class<? extends PropertyValueConverter<S, T, C>> converterType) {
 
 			return delegates.stream().filter(it -> it.getConverter(converterType) != null).findFirst()
@@ -117,7 +117,7 @@ final class PropertyValueConverterFactories {
 
 		@Override
 		@SuppressWarnings("unchecked")
-		public <DV, SV, C extends ValueConversionContext<?>> PropertyValueConverter<DV, SV, C> getConverter(
+		public <DV, SV, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<DV, SV, C> getConverter(
 				Class<? extends PropertyValueConverter<DV, SV, C>> converterType) {
 
 			Assert.notNull(converterType, "ConverterType must not be null");
@@ -151,10 +151,9 @@ final class PropertyValueConverterFactories {
 			this.converterRegistry = converterRegistry;
 		}
 
-		@Nullable
 		@Override
 		@SuppressWarnings("unchecked")
-		public <DV, SV, C extends ValueConversionContext<?>> PropertyValueConverter<DV, SV, C> getConverter(
+		public <DV, SV, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<DV, SV, C> getConverter(
 				PersistentProperty<?> property) {
 
 			return (PropertyValueConverter<DV, SV, C>) converterRegistry.getConverter(property.getOwner().getType(),
@@ -162,7 +161,7 @@ final class PropertyValueConverterFactories {
 		}
 
 		@Override
-		public <S, T, C extends ValueConversionContext<?>> PropertyValueConverter<S, T, C> getConverter(
+		public <S, T, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<S, T, C> getConverter(
 				Class<? extends PropertyValueConverter<S, T, C>> converterType) {
 
 			return null;
@@ -189,10 +188,9 @@ final class PropertyValueConverterFactories {
 			this.delegate = delegate;
 		}
 
-		@Nullable
 		@Override
 		@SuppressWarnings({ "rawtypes", "unchecked" })
-		public <DV, SV, C extends ValueConversionContext<?>> PropertyValueConverter<DV, SV, C> getConverter(
+		public <DV, SV, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<DV, SV, C> getConverter(
 				PersistentProperty<?> property) {
 
 			Optional<PropertyValueConverter<?, ?, ? extends ValueConversionContext<?>>> converter = cache.get(property);
@@ -203,7 +201,7 @@ final class PropertyValueConverterFactories {
 
 		@Override
 		@SuppressWarnings({ "rawtypes", "unchecked" })
-		public <DV, SV, C extends ValueConversionContext<?>> PropertyValueConverter<DV, SV, C> getConverter(
+		public <DV, SV, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<DV, SV, C> getConverter(
 				Class<? extends PropertyValueConverter<DV, SV, C>> converterType) {
 
 			Optional<PropertyValueConverter<?, ?, ? extends ValueConversionContext<?>>> converter = cache.get(converterType);
@@ -227,9 +225,9 @@ final class PropertyValueConverterFactories {
 				return typeCache.get(type);
 			}
 
-			@Nullable
 			@Contract("_, null -> null;_, !null -> !null")
-			<S, T, C extends ValueConversionContext<?>> PropertyValueConverter<S, T, C> cache(PersistentProperty<?> property,
+			<S, T, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<S, T, C> cache(
+					PersistentProperty<?> property,
 					@Nullable PropertyValueConverter<S, T, C> converter) {
 
 				perPropertyCache.putIfAbsent(property, Optional.ofNullable(converter));
@@ -245,9 +243,8 @@ final class PropertyValueConverterFactories {
 				return converter;
 			}
 
-			@Nullable
 			@Contract("_, null -> null;_, !null -> !null")
-			<S, T, C extends ValueConversionContext<?>> PropertyValueConverter<S, T, C> cache(Class<?> type,
+			<S, T, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<S, T, C> cache(Class<?> type,
 					@Nullable PropertyValueConverter<S, T, C> converter) {
 
 				typeCache.putIfAbsent(type, Optional.ofNullable(converter));

src/main/java/org/springframework/data/convert/PropertyValueConverterFactory.java

@@ -18,6 +18,8 @@ package org.springframework.data.convert;
 import java.util.Arrays;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.data.convert.PropertyValueConverterFactories.BeanFactoryAwarePropertyValueConverterFactory;
 import org.springframework.data.convert.PropertyValueConverterFactories.CachingPropertyValueConverterFactory;
@@ -25,7 +27,6 @@ import org.springframework.data.convert.PropertyValueConverterFactories.ChainedP
 import org.springframework.data.convert.PropertyValueConverterFactories.ConfiguredInstanceServingValueConverterFactory;
 import org.springframework.data.convert.PropertyValueConverterFactories.SimplePropertyConverterFactory;
 import org.springframework.data.mapping.PersistentProperty;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -50,8 +51,7 @@ public interface PropertyValueConverterFactory {
 	 * @return can be {@literal null}.
 	 */
 	@SuppressWarnings("unchecked")
-	@Nullable
-	default <DV, SV, P extends ValueConversionContext<?>> PropertyValueConverter<DV, SV, P> getConverter(
+	default <DV, SV, P extends ValueConversionContext<?>> @Nullable PropertyValueConverter<DV, SV, P> getConverter(
 			PersistentProperty<?> property) {
 
 		AnnotatedPropertyValueConverterAccessor accessor = new AnnotatedPropertyValueConverterAccessor(property);
@@ -72,8 +72,7 @@ public interface PropertyValueConverterFactory {
 	 * @param <C> value conversion context to use.
 	 * @return can be {@literal null}.
 	 */
-	@Nullable
-	<DV, SV, C extends ValueConversionContext<?>> PropertyValueConverter<DV, SV, C> getConverter(
+	<DV, SV, C extends ValueConversionContext<?>> @Nullable PropertyValueConverter<DV, SV, C> getConverter(
 			Class<? extends PropertyValueConverter<DV, SV, C>> converterType);
 
 	/**

src/main/java/org/springframework/data/convert/SimplePropertyValueConversions.java

@@ -21,10 +21,11 @@ import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.InitializingBean;
 import org.springframework.data.convert.PropertyValueConverterFactories.ChainedPropertyValueConverterFactory;
 import org.springframework.data.mapping.PersistentProperty;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -60,12 +61,12 @@ public class SimplePropertyValueConversions implements PropertyValueConversions,
 		INSTANCE;
 
 		@Override
-		public Object read(Object value, ValueConversionContext context) {
+		public @Nullable Object read(Object value, ValueConversionContext context) {
 			return null;
 		}
 
 		@Override
-		public Object write(Object value, ValueConversionContext context) {
+		public @Nullable Object write(Object value, ValueConversionContext context) {
 			return null;
 		}
 	}
@@ -88,8 +89,7 @@ public class SimplePropertyValueConversions implements PropertyValueConversions,
 	 * @return the configured {@link PropertyValueConverterFactory}; can be {@literal null}.
 	 * @see PropertyValueConverterFactory
 	 */
-	@Nullable
-	public PropertyValueConverterFactory getConverterFactory() {
+	public @Nullable PropertyValueConverterFactory getConverterFactory() {
 		return converterFactory;
 	}
 
@@ -122,8 +122,7 @@ public class SimplePropertyValueConversions implements PropertyValueConversions,
 	 * @return the configured {@link ValueConverterRegistry}; can be {@literal null}.
 	 * @see ValueConverterRegistry
 	 */
-	@Nullable
-	public ValueConverterRegistry<?> getValueConverterRegistry() {
+	public @Nullable ValueConverterRegistry<?> getValueConverterRegistry() {
 		return valueConverterRegistry;
 	}
 
@@ -163,8 +162,7 @@ public class SimplePropertyValueConversions implements PropertyValueConversions,
 	}
 
 	@SuppressWarnings("unchecked")
-	@Nullable
-	private <DV, SV, P extends PersistentProperty<P>, D extends ValueConversionContext<P>> PropertyValueConverter<DV, SV, D> doGetConverter(
+	private <DV, SV, P extends PersistentProperty<P>, D extends ValueConversionContext<P>> @Nullable PropertyValueConverter<DV, SV, D> doGetConverter(
 			PersistentProperty<?> property) {
 
 		PropertyValueConverter<?, ?, ?> converter = converterCache.get(property);

src/main/java/org/springframework/data/convert/SimplePropertyValueConverterRegistry.java

@@ -18,6 +18,8 @@ package org.springframework.data.convert;
 import java.util.LinkedHashMap;
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.util.ObjectUtils;
 
@@ -68,7 +70,7 @@ public class SimplePropertyValueConverterRegistry<P extends PersistentProperty<P
 
 	@Override
 	@SuppressWarnings("unchecked")
-	public <S, T> PropertyValueConverter<S, T, ? extends ValueConversionContext<P>> getConverter(Class<?> type,
+	public <S, T> @Nullable PropertyValueConverter<S, T, ? extends ValueConversionContext<P>> getConverter(Class<?> type,
 			String path) {
 
 		return (PropertyValueConverter<S, T, ? extends ValueConversionContext<P>>) converterRegistrationMap

src/main/java/org/springframework/data/convert/SimpleTypeInformationMapper.java

@@ -19,10 +19,11 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.BeanClassLoaderAware;
 import org.springframework.data.mapping.Alias;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 
 /**
@@ -48,9 +49,8 @@ public class SimpleTypeInformationMapper implements TypeInformationMapper, BeanC
 	 * @return the type to be used for the given {@link String} representation or {@literal null} if nothing found or the
 	 *         class cannot be loaded.
 	 */
-	@Nullable
 	@Override
-	public TypeInformation<?> resolveTypeFrom(Alias alias) {
+	public @Nullable TypeInformation<?> resolveTypeFrom(Alias alias) {
 
 		String stringAlias = alias.mapTyped(String.class);
 

src/main/java/org/springframework/data/convert/TypeInformationMapper.java

@@ -15,9 +15,10 @@
  */
 package org.springframework.data.convert;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.Alias;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 
 /**
  * Interface to abstract the mapping from a type alias to the actual type.

src/main/java/org/springframework/data/convert/TypeMapper.java

@@ -15,8 +15,9 @@
  */
 package org.springframework.data.convert;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 
 /**
  * Interface to define strategies how to store type information in a store specific sink or source.

src/main/java/org/springframework/data/convert/ValueConversionContext.java

@@ -15,9 +15,10 @@
  */
 package org.springframework.data.convert;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 
 /**
  * The {@link ValueConversionContext} provides access to the store-specific {@link PersistentProperty} and allows to
@@ -50,8 +51,7 @@ public interface ValueConversionContext<P extends PersistentProperty<P>> {
 	 * @see PersistentProperty#getTypeInformation()
 	 * @see #write(Object, TypeInformation)
 	 */
-	@Nullable
-	default Object write(@Nullable Object value) {
+	default @Nullable Object write(@Nullable Object value) {
 		return write(value, getProperty().getTypeInformation());
 	}
 
@@ -65,8 +65,7 @@ public interface ValueConversionContext<P extends PersistentProperty<P>> {
 	 * @see #write(Object, TypeInformation)
 	 * @see TypeInformation
 	 */
-	@Nullable
-	default <T> T write(@Nullable Object value, Class<T> target) {
+	default <T> @Nullable T write(@Nullable Object value, Class<T> target) {
 		return write(value, TypeInformation.of(target));
 	}
 
@@ -79,8 +78,7 @@ public interface ValueConversionContext<P extends PersistentProperty<P>> {
 	 * @throws IllegalStateException if value cannot be written as an instance of {@link TypeInformation type}.
 	 * @see TypeInformation
 	 */
-	@Nullable
-	default <T> T write(@Nullable Object value, TypeInformation<T> target) {
+	default <T> @Nullable T write(@Nullable Object value, TypeInformation<T> target) {
 
 		if (value == null || target.getType().isInstance(value)) {
 			return target.getType().cast(value);
@@ -100,8 +98,7 @@ public interface ValueConversionContext<P extends PersistentProperty<P>> {
 	 * @see PersistentProperty#getTypeInformation()
 	 * @see #read(Object, TypeInformation)
 	 */
-	@Nullable
-	default Object read(@Nullable Object value) {
+	default @Nullable Object read(@Nullable Object value) {
 		return read(value, getProperty().getTypeInformation());
 	}
 
@@ -115,8 +112,7 @@ public interface ValueConversionContext<P extends PersistentProperty<P>> {
 	 * @see #read(Object, TypeInformation)
 	 * @see TypeInformation
 	 */
-	@Nullable
-	default <T> T read(@Nullable Object value, Class<T> target) {
+	default <T> @Nullable T read(@Nullable Object value, Class<T> target) {
 		return read(value, TypeInformation.of(target));
 	}
 
@@ -129,8 +125,7 @@ public interface ValueConversionContext<P extends PersistentProperty<P>> {
 	 * @throws IllegalStateException if value cannot be read as an instance of {@link TypeInformation type}.
 	 * @see TypeInformation
 	 */
-	@Nullable
-	default <T> T read(@Nullable Object value, TypeInformation<T> target) {
+	default <T> @Nullable T read(@Nullable Object value, TypeInformation<T> target) {
 
 		if (value == null || target.getType().isInstance(value)) {
 			return target.getType().cast(value);

src/main/java/org/springframework/data/convert/ValueConverterRegistry.java

@@ -15,8 +15,9 @@
  */
 package org.springframework.data.convert;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.PersistentProperty;
-import org.springframework.lang.Nullable;
 
 /**
  * A registry of {@link PersistentProperty property-specific} {@link PropertyValueConverter value converters}
@@ -48,8 +49,8 @@ public interface ValueConverterRegistry<P extends PersistentProperty<P>> {
 	 * @param <SV> store-specific type.
 	 * @return {@literal null} if no converter present for the given type/path combination.
 	 */
-	@Nullable
-	<DV, SV> PropertyValueConverter<DV, SV, ? extends ValueConversionContext<P>> getConverter(Class<?> type, String path);
+	<DV, SV> @Nullable PropertyValueConverter<DV, SV, ? extends ValueConversionContext<P>> getConverter(Class<?> type,
+			String path);
 
 	/**
 	 * Check if a converter is registered for the given type, path combination.

src/main/java/org/springframework/data/convert/package-info.java

@@ -3,5 +3,5 @@
  * 
  * @see org.springframework.data.convert.EntityConverter
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.convert;

src/main/java/org/springframework/data/crossstore/ChangeSet.java

@@ -17,8 +17,9 @@ package org.springframework.data.crossstore;
 
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.ConversionService;
-import org.springframework.lang.Nullable;
 
 /**
  * Interface representing the set of changes in an entity.
@@ -28,8 +29,7 @@ import org.springframework.lang.Nullable;
  */
 public interface ChangeSet {
 
-	@Nullable
-	<T> T get(String key, Class<T> requiredClass, ConversionService cs);
+	<T> @Nullable T get(String key, Class<T> requiredClass, ConversionService cs);
 
 	void set(String key, Object o);
 

src/main/java/org/springframework/data/crossstore/HashMapChangeSet.java

@@ -19,8 +19,9 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.ConversionService;
-import org.springframework.lang.Nullable;
 
 /**
  * Simple ChangeSet implementation backed by a HashMap.
@@ -56,14 +57,12 @@ public class HashMapChangeSet implements ChangeSet {
 	}
 
 	@Override
-	@Nullable
-	public Object removeProperty(String k) {
+	public @Nullable Object removeProperty(String k) {
 		return this.values.remove(k);
 	}
 
 	@Override
-	@Nullable
-	public <T> T get(String key, Class<T> requiredClass, ConversionService conversionService) {
+	public <T> @Nullable T get(String key, Class<T> requiredClass, ConversionService conversionService) {
 
 		Object value = values.get(key);
 

src/main/java/org/springframework/data/crossstore/package-info.java

@@ -1,5 +1,5 @@
 /**
  * Support for cross-store persistence.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.crossstore;

src/main/java/org/springframework/data/domain/Auditable.java

@@ -18,7 +18,7 @@ package org.springframework.data.domain;
 import java.time.temporal.TemporalAccessor;
 import java.util.Optional;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Interface for auditable entities. Allows storing and retrieving creation and modification information. The changing

src/main/java/org/springframework/data/domain/ExampleMatcher.java

@@ -22,9 +22,10 @@ import java.util.Optional;
 import java.util.Set;
 import java.util.function.Function;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.lang.CheckReturnValue;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
@@ -608,7 +609,7 @@ public interface ExampleMatcher {
 	 * @author Mark Paluch
 	 * @since 1.12
 	 */
-	class PropertySpecifier {
+	static class PropertySpecifier {
 
 		private final String path;
 		private final @Nullable StringMatcher stringMatcher;
@@ -692,16 +693,14 @@ public interface ExampleMatcher {
 		 *
 		 * @return can be {@literal null}.
 		 */
-		@Nullable
-		public StringMatcher getStringMatcher() {
+		public @Nullable StringMatcher getStringMatcher() {
 			return stringMatcher;
 		}
 
 		/**
 		 * @return {@literal null} if not set.
 		 */
-		@Nullable
-		public Boolean getIgnoreCase() {
+		public @Nullable Boolean getIgnoreCase() {
 			return ignoreCase;
 		}
 
@@ -711,7 +710,7 @@ public interface ExampleMatcher {
 		 * @return never {@literal null}.
 		 */
 		public PropertyValueTransformer getPropertyValueTransformer() {
-			return valueTransformer == null ? NoOpPropertyValueTransformer.INSTANCE : valueTransformer;
+			return valueTransformer;
 		}
 
 		/**
@@ -772,7 +771,7 @@ public interface ExampleMatcher {
 		private final Map<String, PropertySpecifier> propertySpecifiers;
 
 		PropertySpecifiers() {
-			this. propertySpecifiers = new LinkedHashMap<>();
+			this.propertySpecifiers = new LinkedHashMap<>();
 		}
 
 		PropertySpecifiers(PropertySpecifiers propertySpecifiers) {
@@ -789,10 +788,21 @@ public interface ExampleMatcher {
 			return propertySpecifiers.containsKey(path);
 		}
 
-		public PropertySpecifier getForPath(String path) {
+		public @Nullable PropertySpecifier getForPath(String path) {
 			return propertySpecifiers.get(path);
 		}
 
+		public PropertySpecifier getRequiredForPath(String path) {
+
+			PropertySpecifier specifier = getForPath(path);
+
+			if (specifier == null) {
+				throw new IllegalArgumentException("No PropertySpecifier found for path '%s'".formatted(path));
+			}
+
+			return specifier;
+		}
+
 		public boolean hasValues() {
 			return !propertySpecifiers.isEmpty();
 		}

src/main/java/org/springframework/data/domain/KeysetScrollPosition.java

@@ -20,7 +20,8 @@ import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Objects;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/domain/Limit.java

@@ -15,9 +15,10 @@
  */
 package org.springframework.data.domain;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.Limit.Limited;
 import org.springframework.data.domain.Limit.Unlimited;
-import org.springframework.lang.Nullable;
 
 /**
  * {@link Limit} represents the maximum value up to which an operation should continue processing. It may be used for

src/main/java/org/springframework/data/domain/OffsetScrollPosition.java

@@ -18,7 +18,8 @@ package org.springframework.data.domain;
 import java.util.Objects;
 import java.util.function.IntFunction;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 
 /**

src/main/java/org/springframework/data/domain/PageImpl.java

@@ -19,7 +19,8 @@ import java.io.Serial;
 import java.util.List;
 import java.util.function.Function;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.CollectionUtils;
 
 /**

src/main/java/org/springframework/data/domain/PageRequest.java

@@ -20,7 +20,6 @@ import java.io.Serial;
 import org.springframework.data.domain.Sort.Direction;
 import org.springframework.lang.CheckReturnValue;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/domain/Pageable.java

@@ -130,7 +130,7 @@ public interface Pageable {
 	 *
 	 * @return the {@link Pageable} requesting the next {@link Page}.
 	 */
-	@Contract("_ -> new")
+	@Contract("-> new")
 	@CheckReturnValue
 	Pageable next();
 
@@ -139,7 +139,7 @@ public interface Pageable {
 	 *
 	 * @return the previous {@link Pageable} or the first {@link Pageable} if the current one already is the first one.
 	 */
-	@Contract("_ -> new")
+	@Contract("-> new")
 	@CheckReturnValue
 	Pageable previousOrFirst();
 
@@ -148,7 +148,7 @@ public interface Pageable {
 	 *
 	 * @return the {@link Pageable} requesting the first page.
 	 */
-	@Contract("_ -> new")
+	@Contract("-> new")
 	@CheckReturnValue
 	Pageable first();
 

src/main/java/org/springframework/data/domain/Persistable.java

@@ -15,7 +15,7 @@
  */
 package org.springframework.data.domain;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Simple interface for entities.

src/main/java/org/springframework/data/domain/Range.java

@@ -19,7 +19,8 @@ import java.util.Comparator;
 import java.util.Optional;
 import java.util.function.Function;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/domain/SliceImpl.java

@@ -19,7 +19,7 @@ import java.io.Serial;
 import java.util.List;
 import java.util.function.Function;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Default implementation of {@link Slice}.

src/main/java/org/springframework/data/domain/Sort.java

@@ -27,12 +27,13 @@ import java.util.Optional;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.util.MethodInvocationRecorder;
 import org.springframework.data.util.MethodInvocationRecorder.Recorded;
 import org.springframework.data.util.Streamable;
 import org.springframework.lang.CheckReturnValue;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;
@@ -251,8 +252,7 @@ public class Sort implements Streamable<org.springframework.data.domain.Sort.Ord
 	 * @param property name of the property that should be sorted.
 	 * @return the sort {@link Order} or {@literal null} if the property is not sorted by.
 	 */
-	@Nullable
-	public Order getOrderFor(String property) {
+	public @Nullable Order getOrderFor(String property) {
 
 		for (Order order : this) {
 			if (order.getProperty().equals(property)) {

src/main/java/org/springframework/data/domain/TypedExample.java

@@ -15,7 +15,8 @@
  */
 package org.springframework.data.domain;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/domain/TypedExampleMatcher.java

@@ -20,7 +20,8 @@ import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.Set;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 
@@ -188,13 +189,12 @@ class TypedExampleMatcher implements ExampleMatcher {
 	private PropertySpecifier getOrCreatePropertySpecifier(String propertyPath, PropertySpecifiers propertySpecifiers) {
 
 		if (propertySpecifiers.hasSpecifierForPath(propertyPath)) {
-			return propertySpecifiers.getForPath(propertyPath);
+			return propertySpecifiers.getRequiredForPath(propertyPath);
 		}
 
 		return new PropertySpecifier(propertyPath);
 	}
 
-
 	@Override
 	public boolean equals(@Nullable Object o) {
 

src/main/java/org/springframework/data/domain/Unpaged.java

@@ -15,7 +15,7 @@
  */
 package org.springframework.data.domain;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * {@link Pageable} implementation to represent the absence of pagination information.

src/main/java/org/springframework/data/domain/WindowImpl.java

@@ -21,9 +21,8 @@ import java.util.function.Function;
 import java.util.function.IntFunction;
 import java.util.stream.Collectors;
 
-import org.jetbrains.annotations.NotNull;
+import org.jspecify.annotations.Nullable;
 
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/domain/jaxb/OrderAdapter.java

@@ -17,11 +17,12 @@ package org.springframework.data.domain.jaxb;
 
 import jakarta.xml.bind.annotation.adapters.XmlAdapter;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.Sort;
 import org.springframework.data.domain.Sort.Order;
 import org.springframework.data.domain.jaxb.SpringDataJaxb.OrderDto;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 
 /**
  * XmlAdapter to convert {@link Order} instances into {@link OrderDto}s and vice versa.
@@ -32,9 +33,8 @@ public class OrderAdapter extends XmlAdapter<OrderDto, Order> {
 
 	public static final OrderAdapter INSTANCE = new OrderAdapter();
 
-	@Nullable
 	@Override
-	public OrderDto marshal(@Nullable Order order) {
+	public @Nullable OrderDto marshal(@Nullable Order order) {
 
 		if (order == null) {
 			return null;
@@ -46,10 +46,9 @@ public class OrderAdapter extends XmlAdapter<OrderDto, Order> {
 		return dto;
 	}
 
-	@Nullable
 	@Contract("null -> null")
 	@Override
-	public Order unmarshal(@Nullable OrderDto source) {
+	public @Nullable Order unmarshal(@Nullable OrderDto source) {
 
 		if (source == null) {
 			return null;

src/main/java/org/springframework/data/domain/jaxb/PageAdapter.java

@@ -20,11 +20,12 @@ import jakarta.xml.bind.annotation.adapters.XmlAdapter;
 import java.util.Collections;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.jaxb.SpringDataJaxb.PageDto;
 import org.springframework.hateoas.Link;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 
 /**
  * {@link XmlAdapter} to convert {@link Page} instances into {@link PageDto} instances and vice versa.
@@ -33,10 +34,9 @@ import org.springframework.lang.Nullable;
  */
 public class PageAdapter extends XmlAdapter<PageDto, Page<Object>> {
 
-	@Nullable
 	@Contract("null -> null; !null -> !null")
 	@Override
-	public PageDto marshal(@Nullable Page<Object> source) {
+	public @Nullable PageDto marshal(@Nullable Page<Object> source) {
 
 		if (source == null) {
 			return null;
@@ -49,10 +49,9 @@ public class PageAdapter extends XmlAdapter<PageDto, Page<Object>> {
 		return dto;
 	}
 
-	@Nullable
 	@Contract("_ -> null")
 	@Override
-	public Page<Object> unmarshal(@Nullable PageDto v) {
+	public @Nullable Page<Object> unmarshal(@Nullable PageDto v) {
 		return null;
 	}
 

src/main/java/org/springframework/data/domain/jaxb/PageableAdapter.java

@@ -19,12 +19,13 @@ import jakarta.xml.bind.annotation.adapters.XmlAdapter;
 
 import java.util.Collections;
 
+import org.jspecify.annotations.NonNull;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.domain.jaxb.SpringDataJaxb.PageRequestDto;
 import org.springframework.data.domain.jaxb.SpringDataJaxb.SortDto;
-import org.springframework.lang.NonNull;
-import org.springframework.lang.Nullable;
 
 /**
  * {@link XmlAdapter} to convert {@link Pageable} instances int a {@link PageRequestDto} and vice versa.
@@ -34,9 +35,8 @@ import org.springframework.lang.Nullable;
  */
 class PageableAdapter extends XmlAdapter<PageRequestDto, Pageable> {
 
-	@Nullable
 	@Override
-	public PageRequestDto marshal(@Nullable Pageable request) {
+	public @Nullable PageRequestDto marshal(@Nullable Pageable request) {
 
 		if (request == null) {
 			return null;

src/main/java/org/springframework/data/domain/jaxb/SortAdapter.java

@@ -17,11 +17,12 @@ package org.springframework.data.domain.jaxb;
 
 import jakarta.xml.bind.annotation.adapters.XmlAdapter;
 
+import org.jspecify.annotations.NonNull;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.Sort;
 import org.springframework.data.domain.jaxb.SpringDataJaxb.SortDto;
 import org.springframework.lang.Contract;
-import org.springframework.lang.NonNull;
-import org.springframework.lang.Nullable;
 
 /**
  * {@link XmlAdapter} to convert {@link Sort} instances into {@link SortDto} instances and vice versa.
@@ -32,10 +33,9 @@ public class SortAdapter extends XmlAdapter<SortDto, Sort> {
 
 	public static final SortAdapter INSTANCE = new SortAdapter();
 
-	@Nullable
 	@Contract("null -> null; !null -> !null")
 	@Override
-	public SortDto marshal(@Nullable Sort source) {
+	public @Nullable SortDto marshal(@Nullable Sort source) {
 
 		if (source == null) {
 			return null;

src/main/java/org/springframework/data/domain/jaxb/SpringDataJaxb.java

@@ -29,6 +29,8 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageRequest;
 import org.springframework.data.domain.Pageable;
@@ -36,7 +38,6 @@ import org.springframework.data.domain.Sort;
 import org.springframework.data.domain.Sort.Direction;
 import org.springframework.data.domain.Sort.Order;
 import org.springframework.hateoas.RepresentationModel;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**

src/main/java/org/springframework/data/domain/jaxb/package-info.java

@@ -10,7 +10,7 @@
 		@XmlJavaTypeAdapter(value = org.springframework.data.domain.jaxb.PageableAdapter.class, type = Pageable.class),
 		@XmlJavaTypeAdapter(value = org.springframework.data.domain.jaxb.SortAdapter.class, type = Sort.class),
 		@XmlJavaTypeAdapter(value = org.springframework.data.domain.jaxb.PageAdapter.class, type = Page.class) })
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.domain.jaxb;
 
 import jakarta.xml.bind.annotation.XmlNs;

src/main/java/org/springframework/data/domain/package-info.java

@@ -4,5 +4,5 @@
  *
  * @see org.springframework.data.repository.Repository
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.domain;

src/main/java/org/springframework/data/expression/DefaultValueEvaluationContext.java

@@ -17,7 +17,6 @@ package org.springframework.data.expression;
 
 import org.springframework.core.env.Environment;
 import org.springframework.expression.EvaluationContext;
-import org.springframework.lang.Nullable;
 
 /**
  * Default {@link ValueEvaluationContext}.
@@ -25,7 +24,7 @@ import org.springframework.lang.Nullable;
  * @author Mark Paluch
  * @since 3.3
  */
-record DefaultValueEvaluationContext(@Nullable Environment environment,
+record DefaultValueEvaluationContext(Environment environment,
 		EvaluationContext evaluationContext) implements ValueEvaluationContext {
 
 	@Override

src/main/java/org/springframework/data/expression/ExpressionExpression.java

@@ -15,6 +15,8 @@
  */
 package org.springframework.data.expression;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.spel.ExpressionDependencies;
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.Expression;
@@ -44,14 +46,14 @@ record ExpressionExpression(Expression expression, ExpressionDependencies depend
 	}
 
 	@Override
-	public Object evaluate(ValueEvaluationContext context) {
+	public @Nullable Object evaluate(ValueEvaluationContext context) {
 
 		EvaluationContext evaluationContext = context.getEvaluationContext();
 		return evaluationContext != null ? expression.getValue(evaluationContext) : expression.getValue();
 	}
 
 	@Override
-	public Class<?> getValueType(ValueEvaluationContext context) {
+	public @Nullable Class<?> getValueType(ValueEvaluationContext context) {
 
 		EvaluationContext evaluationContext = context.getEvaluationContext();
 		return evaluationContext != null ? expression.getValueType(evaluationContext) : expression.getValueType();

src/main/java/org/springframework/data/expression/PlaceholderExpression.java

@@ -38,6 +38,7 @@ record PlaceholderExpression(String expression) implements ValueExpression {
 	}
 
 	@Override
+	@SuppressWarnings("NullAway")
 	public String evaluate(ValueEvaluationContext context) {
 
 		Environment environment = context.getEnvironment();

src/main/java/org/springframework/data/expression/ReactiveValueEvaluationContextProvider.java

@@ -17,8 +17,9 @@ package org.springframework.data.expression;
 
 import reactor.core.publisher.Mono;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.spel.ExpressionDependencies;
-import org.springframework.lang.Nullable;
 
 /**
  * Reactive extension to {@link ValueEvaluationContext} for obtaining a {@link ValueEvaluationContext} that participates

src/main/java/org/springframework/data/expression/ValueEvaluationContext.java

@@ -17,7 +17,6 @@ package org.springframework.data.expression;
 
 import org.springframework.core.env.Environment;
 import org.springframework.expression.EvaluationContext;
-import org.springframework.lang.Nullable;
 
 /**
  * Expressions are executed in an evaluation context. It is in this context that references are resolved when
@@ -36,24 +35,22 @@ public interface ValueEvaluationContext {
 	 * @param evaluationContext
 	 * @return a new {@link ValueEvaluationContext} for the given environment and evaluation context.
 	 */
-	static ValueEvaluationContext of(@Nullable Environment environment, EvaluationContext evaluationContext) {
+	static ValueEvaluationContext of(Environment environment, EvaluationContext evaluationContext) {
 		return new DefaultValueEvaluationContext(environment, evaluationContext);
 	}
 
 	/**
 	 * Returns the {@link Environment} if provided.
 	 *
-	 * @return the {@link Environment} or {@literal null}.
+	 * @return the {@link Environment}.
 	 */
-	@Nullable
 	Environment getEnvironment();
 
 	/**
 	 * Returns the {@link EvaluationContext} if provided.
 	 *
-	 * @return the {@link EvaluationContext} or {@literal null} if not set.
+	 * @return the {@link EvaluationContext}.
 	 */
-	@Nullable
 	EvaluationContext getEvaluationContext();
 
 	/**
@@ -62,7 +59,10 @@ public interface ValueEvaluationContext {
 	 *
 	 * @return the {@link EvaluationContext}.
 	 * @since 3.4
+	 * @deprecated since 4.0, EvaluationContext is always provided.
 	 */
+	@Deprecated
+	@SuppressWarnings("ConstantValue")
 	default EvaluationContext getRequiredEvaluationContext() {
 
 		EvaluationContext evaluationContext = getEvaluationContext();

src/main/java/org/springframework/data/expression/ValueEvaluationContextProvider.java

@@ -15,9 +15,10 @@
  */
 package org.springframework.data.expression;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.spel.ExpressionDependencies;
 import org.springframework.expression.EvaluationContext;
-import org.springframework.lang.Nullable;
 
 /**
  * SPI to provide to access a centrally defined potentially shared {@link ValueEvaluationContext}.

src/main/java/org/springframework/data/expression/ValueExpression.java

@@ -15,9 +15,10 @@
  */
 package org.springframework.data.expression;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.spel.ExpressionDependencies;
 import org.springframework.expression.EvaluationException;
-import org.springframework.lang.Nullable;
 
 /**
  * An expression capable of evaluating itself against context objects. Encapsulates the details of a previously parsed

src/main/java/org/springframework/data/expression/package-info.java

@@ -1,5 +1,5 @@
 /**
  * Value Expression implementation.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.expression;

src/main/java/org/springframework/data/geo/Box.java

@@ -17,7 +17,8 @@ package org.springframework.data.geo;
 
 import java.io.Serial;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/geo/Circle.java

@@ -17,8 +17,9 @@ package org.springframework.data.geo;
 
 import java.io.Serial;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.annotation.PersistenceCreator;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/geo/Distance.java

@@ -18,11 +18,12 @@ package org.springframework.data.geo;
 import java.io.Serial;
 import java.io.Serializable;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.Range;
 import org.springframework.data.domain.Range.Bound;
 import org.springframework.lang.CheckReturnValue;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/geo/GeoPage.java

@@ -17,10 +17,11 @@ package org.springframework.data.geo;
 
 import java.io.Serial;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageImpl;
 import org.springframework.data.domain.Pageable;
-import org.springframework.lang.Nullable;
 import org.springframework.util.ObjectUtils;
 
 /**

src/main/java/org/springframework/data/geo/GeoResult.java

@@ -18,7 +18,8 @@ package org.springframework.data.geo;
 import java.io.Serial;
 import java.io.Serializable;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/geo/GeoResults.java

@@ -22,8 +22,9 @@ import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.annotation.PersistenceCreator;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;

src/main/java/org/springframework/data/geo/Point.java

@@ -19,8 +19,9 @@ import java.io.Serial;
 import java.io.Serializable;
 import java.util.Locale;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.annotation.PersistenceCreator;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 

src/main/java/org/springframework/data/geo/Polygon.java

@@ -23,8 +23,9 @@ import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.annotation.PersistenceCreator;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ObjectUtils;
 import org.springframework.util.StringUtils;

src/main/java/org/springframework/data/geo/format/DistanceFormatter.java

@@ -22,13 +22,14 @@ import java.util.Locale;
 import java.util.Map;
 import java.util.Map.Entry;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.geo.Distance;
 import org.springframework.data.geo.Metric;
 import org.springframework.data.geo.Metrics;
 import org.springframework.format.Formatter;
 import org.springframework.lang.Contract;
-import org.springframework.lang.Nullable;
 import org.springframework.util.StringUtils;
 
 /**
@@ -59,9 +60,8 @@ public enum DistanceFormatter implements Converter<String, Distance>, Formatter<
 	}
 
 	@Contract("null -> null; !null -> !null")
-	@Nullable
 	@Override
-	public final Distance convert(@Nullable String source) {
+	public final @Nullable Distance convert(@Nullable String source) {
 		return source == null ? null : doConvert(source.trim().toLowerCase(Locale.US));
 	}
 

src/main/java/org/springframework/data/geo/format/PointFormatter.java

@@ -18,12 +18,13 @@ package org.springframework.data.geo.format;
 import java.text.ParseException;
 import java.util.Locale;
 
+import org.jspecify.annotations.NonNull;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.core.convert.converter.GenericConverter.ConvertiblePair;
 import org.springframework.data.geo.Point;
 import org.springframework.format.Formatter;
-import org.springframework.lang.NonNull;
-import org.springframework.lang.Nullable;
 
 /**
  * Converter to parse two comma-separated doubles into a {@link Point}.

src/main/java/org/springframework/data/geo/format/package-info.java

@@ -4,5 +4,5 @@
  * @author Oliver Gierke
  * @since 1.8
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.geo.format;

src/main/java/org/springframework/data/geo/package-info.java

@@ -5,5 +5,5 @@
  * @author Oliver Gierke
  * @since 1.8
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.geo;

src/main/java/org/springframework/data/history/Revision.java

@@ -20,7 +20,8 @@ import static org.springframework.data.util.Optionals.*;
 import java.time.Instant;
 import java.util.Optional;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.ObjectUtils;
 
 /**

src/main/java/org/springframework/data/history/package-info.java

@@ -1,5 +1,5 @@
 /**
  * Basic interfaces and value objects for histography API.
  */
-@org.springframework.lang.NonNullApi
+@org.jspecify.annotations.NullMarked
 package org.springframework.data.history;

src/main/java/org/springframework/data/mapping/AccessOptions.java

@@ -22,8 +22,9 @@ import java.util.Map;
 import java.util.Set;
 import java.util.function.Function;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.AccessOptions.SetOptions.SetNulls;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -34,6 +35,7 @@ import org.springframework.util.Assert;
  * @author Oliver Drotbohm
  * @since 2.3
  */
+@SuppressWarnings("NullAway")
 public class AccessOptions {
 
 	/**
@@ -64,10 +66,11 @@ public class AccessOptions {
 
 		private static final GetOptions DEFAULT = new GetOptions(new HashMap<>(), GetNulls.REJECT);
 
-		private final Map<PersistentProperty<?>, Function<Object, Object>> handlers;
+		private final Map<PersistentProperty<?>, Function<@Nullable Object, @Nullable Object>> handlers;
 		private final GetNulls nullValues;
 
-		public GetOptions(Map<PersistentProperty<?>, Function<Object, Object>> handlers, GetNulls nullValues) {
+		public GetOptions(Map<PersistentProperty<?>, Function<@Nullable Object, @Nullable Object>> handlers,
+				GetNulls nullValues) {
 
 			this.handlers = handlers;
 			this.nullValues = nullValues;
@@ -110,12 +113,13 @@ public class AccessOptions {
 		 * @param handler must not be {@literal null}.
 		 * @return
 		 */
-		public GetOptions registerHandler(PersistentProperty<?> property, Function<Object, Object> handler) {
+		public GetOptions registerHandler(PersistentProperty<?> property,
+				Function<@Nullable Object, @Nullable Object> handler) {
 
 			Assert.notNull(property, "Property must not be null");
 			Assert.notNull(handler, "Handler must not be null");
 
-			Map<PersistentProperty<?>, Function<Object, Object>> newHandlers = new HashMap<>(handlers);
+			Map<PersistentProperty<?>, Function<@Nullable Object, @Nullable Object>> newHandlers = new HashMap<>(handlers);
 			newHandlers.put(property, handler);
 
 			return new GetOptions(newHandlers, nullValues);
@@ -130,7 +134,7 @@ public class AccessOptions {
 		 */
 		@SuppressWarnings("unchecked")
 		public GetOptions registerCollectionHandler(PersistentProperty<?> property,
-				Function<? super Collection<?>, Object> handler) {
+				Function<? super Collection<?>, @Nullable Object> handler) {
 			return registerHandler(property, Collection.class, (Function<Object, Object>) handler);
 		}
 
@@ -142,7 +146,8 @@ public class AccessOptions {
 		 * @return
 		 */
 		@SuppressWarnings("unchecked")
-		public GetOptions registerListHandler(PersistentProperty<?> property, Function<? super List<?>, Object> handler) {
+		public GetOptions registerListHandler(PersistentProperty<?> property,
+				Function<? super List<?>, @Nullable Object> handler) {
 			return registerHandler(property, List.class, (Function<Object, Object>) handler);
 		}
 
@@ -154,7 +159,8 @@ public class AccessOptions {
 		 * @return
 		 */
 		@SuppressWarnings("unchecked")
-		public GetOptions registerSetHandler(PersistentProperty<?> property, Function<? super Set<?>, Object> handler) {
+		public GetOptions registerSetHandler(PersistentProperty<?> property,
+				Function<? super Set<?>, @Nullable Object> handler) {
 			return registerHandler(property, Set.class, (Function<Object, Object>) handler);
 		}
 
@@ -166,7 +172,8 @@ public class AccessOptions {
 		 * @return
 		 */
 		@SuppressWarnings("unchecked")
-		public GetOptions registerMapHandler(PersistentProperty<?> property, Function<? super Map<?, ?>, Object> handler) {
+		public GetOptions registerMapHandler(PersistentProperty<?> property,
+				Function<? super Map<?, ?>, @Nullable Object> handler) {
 			return registerHandler(property, Map.class, (Function<Object, Object>) handler);
 		}
 
@@ -201,7 +208,7 @@ public class AccessOptions {
 		@Nullable
 		Object postProcess(PersistentProperty<?> property, @Nullable Object value) {
 
-			Function<Object, Object> handler = handlers.get(property);
+			Function<@Nullable Object, @Nullable Object> handler = handlers.get(property);
 
 			return handler == null ? value : handler.apply(value);
 		}

src/main/java/org/springframework/data/mapping/Alias.java

@@ -18,7 +18,8 @@ package org.springframework.data.mapping;
 import java.util.NoSuchElementException;
 import java.util.Objects;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.util.Assert;
 
 /**
@@ -87,6 +88,7 @@ public final class Alias {
 	 * @param other must not be {@literal null}.
 	 * @return {@literal true} if this value is present but different from the {@code other} value.
 	 */
+	@SuppressWarnings("NullAway")
 	public boolean isPresentButDifferent(Alias other) {
 
 		Assert.notNull(other, "Other alias must not be null");
@@ -100,8 +102,9 @@ public final class Alias {
 	 * @param that the other value, may be {@literal null}.
 	 * @return {@literal true} if this alias has a value and it equals to {@code that}.
 	 */
+	@SuppressWarnings("NullAway")
 	public boolean hasValue(Object that) {
-		return value != null && value.equals(that);
+		return isPresent() && value.equals(that);
 	}
 
 	/**
@@ -110,6 +113,7 @@ public final class Alias {
 	 * @param other the other {@link Alias}
 	 * @return {@literal true} if there's an alias value present and its equal to the one in the given {@link Alias}.
 	 */
+	@SuppressWarnings("NullAway")
 	public boolean hasSamePresentValueAs(Alias other) {
 		return isPresent() && value.equals(other.value);
 	}
@@ -185,6 +189,7 @@ public final class Alias {
 	}
 
 	@Override
+	@SuppressWarnings("NullAway")
 	public String toString() {
 		return isPresent() ? value.toString() : "NONE";
 	}

src/main/java/org/springframework/data/mapping/Association.java

@@ -15,7 +15,7 @@
  */
 package org.springframework.data.mapping;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Value object to capture {@link Association}s.
@@ -44,8 +44,7 @@ public class Association<P extends PersistentProperty<P>> {
 		return inverse;
 	}
 
-	@Nullable
-	public P getObverse() {
+	public @Nullable P getObverse() {
 		return obverse;
 	}
 }

src/main/java/org/springframework/data/mapping/IdentifierAccessor.java

@@ -15,7 +15,7 @@
  */
 package org.springframework.data.mapping;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * Interface for a component allowing the access of identifier values.

src/main/java/org/springframework/data/mapping/MappingException.java

@@ -17,7 +17,7 @@ package org.springframework.data.mapping;
 
 import java.io.Serial;
 
-import org.springframework.lang.Nullable;
+import org.jspecify.annotations.Nullable;
 
 /**
  * @author Jon Brisbin

src/main/java/org/springframework/data/mapping/Parameter.java

@@ -18,11 +18,12 @@ package org.springframework.data.mapping;
 import java.lang.annotation.Annotation;
 import java.util.Objects;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.beans.factory.annotation.Value;
 import org.springframework.core.annotation.MergedAnnotations;
 import org.springframework.data.util.Lazy;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.StringUtils;
@@ -81,8 +82,7 @@ public class Parameter<T, P extends PersistentProperty<P>> {
 		this.hasExpression = Lazy.of(() -> StringUtils.hasText(getValueExpression()));
 	}
 
-	@Nullable
-	private static String getValue(MergedAnnotations annotations) {
+	private static @Nullable String getValue(MergedAnnotations annotations) {
 
 		return annotations.get(Value.class) //
 				.getValue("value", String.class) //
@@ -96,8 +96,7 @@ public class Parameter<T, P extends PersistentProperty<P>> {
 	 * @return the name of the parameter.
 	 * @see org.springframework.core.ParameterNameDiscoverer
 	 */
-	@Nullable
-	public String getName() {
+	public @Nullable String getName() {
 		return name;
 	}
 
@@ -184,7 +183,7 @@ public class Parameter<T, P extends PersistentProperty<P>> {
 	 * @return the expression to be used when looking up a source data structure.
 	 * @since 3.3
 	 */
-	@SuppressWarnings("DataFlowIssue")
+	@SuppressWarnings({ "DataFlowIssue", "NullAway" })
 	public String getRequiredValueExpression() {
 
 		if (!hasValueExpression()) {

src/main/java/org/springframework/data/mapping/PersistentEntity.java

@@ -18,9 +18,10 @@ package org.springframework.data.mapping;
 import java.lang.annotation.Annotation;
 import java.util.Iterator;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.annotation.Immutable;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -170,8 +171,7 @@ public interface PersistentEntity<T, P extends PersistentProperty<P>> extends It
 	 * @return {@literal null} if no property found with given annotation type.
 	 * @since 1.8
 	 */
-	@Nullable
-	default P getPersistentProperty(Class<? extends Annotation> annotationType) {
+	default @Nullable P getPersistentProperty(Class<? extends Annotation> annotationType) {
 
 		Iterator<P> it = getPersistentProperties(annotationType).iterator();
 		return it.hasNext() ? it.next() : null;
@@ -279,8 +279,7 @@ public interface PersistentEntity<T, P extends PersistentProperty<P>> extends It
 	 * @return {@literal null} if not found.
 	 * @since 1.8
 	 */
-	@Nullable
-	<A extends Annotation> A findAnnotation(Class<A> annotationType);
+	<A extends Annotation> @Nullable A findAnnotation(Class<A> annotationType);
 
 	/**
 	 * Returns the required annotation of the given type on the {@link PersistentEntity}.

src/main/java/org/springframework/data/mapping/PersistentProperty.java

@@ -21,10 +21,11 @@ import java.lang.reflect.Method;
 import java.util.Collection;
 import java.util.Map;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.annotation.AnnotatedElementUtils;
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**

src/main/java/org/springframework/data/mapping/PersistentPropertyAccessor.java

@@ -15,8 +15,9 @@
  */
 package org.springframework.data.mapping;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.model.ConvertingPropertyAccessor;
-import org.springframework.lang.Nullable;
 
 /**
  * Domain service to allow accessing and setting {@link PersistentProperty}s of an entity. Usually obtained through

src/main/java/org/springframework/data/mapping/PersistentPropertyPath.java

@@ -15,9 +15,10 @@
  */
 package org.springframework.data.mapping;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.util.Streamable;
-import org.springframework.lang.Nullable;
 
 /**
  * Abstraction of a path of {@link PersistentProperty}s.

src/main/java/org/springframework/data/mapping/PersistentPropertyPathAccessor.java

@@ -15,9 +15,10 @@
  */
 package org.springframework.data.mapping;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.mapping.AccessOptions.GetOptions;
 import org.springframework.data.mapping.AccessOptions.SetOptions;
-import org.springframework.lang.Nullable;
 
 /**
  * Extension of {@link PersistentPropertyAccessor} that is also able to obtain and set values for

src/main/java/org/springframework/data/mapping/PropertyPath.java

@@ -26,9 +26,10 @@ import java.util.Stack;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import org.jspecify.annotations.Nullable;
+
 import org.springframework.data.util.Streamable;
 import org.springframework.data.util.TypeInformation;
-import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.ConcurrentReferenceHashMap;
 import org.springframework.util.StringUtils;
@@ -102,8 +103,7 @@ public class PropertyPath implements Streamable<PropertyPath> {
 				: this.typeInformation.getRequiredActualType();
 	}
 
-	@Nullable
-	private static Property lookupProperty(TypeInformation<?> owningType, String name) {
+	private static @Nullable Property lookupProperty(TypeInformation<?> owningType, String name) {
 
 		TypeInformation<?> propertyType = owningType.getProperty(name);
 
@@ -185,8 +185,7 @@ public class PropertyPath implements Streamable<PropertyPath> {
 	 * @return the next nested {@link PropertyPath} or {@literal null} if no nested {@link PropertyPath} available.
 	 * @see #hasNext()
 	 */
-	@Nullable
-	public PropertyPath next() {
+	public @Nullable PropertyPath next() {
 		return next;
 	}
 
@@ -268,8 +267,7 @@ public class PropertyPath implements Streamable<PropertyPath> {
 			}
 
 			@Override
-			@Nullable
-			public PropertyPath next() {
+			public @Nullable PropertyPath next() {
 
 				PropertyPath result = current;