Add more @Nullable parameters based on null usage

Issue: SPR-15540

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

@@ -189,7 +189,7 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 	 * @param nestedPath the nested path of the object
 	 * @param rootObject the root object at the top of the path
 	 */
-	public void setWrappedInstance(Object object, String nestedPath, Object rootObject) {
+	public void setWrappedInstance(Object object, String nestedPath, @Nullable Object rootObject) {
 		this.wrappedObject = ObjectUtils.unwrapOptional(object);
 		Assert.notNull(this.wrappedObject, "Target object must not be null");
 		this.nestedPath = (nestedPath != null ? nestedPath : "");
@@ -567,7 +567,7 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 		return false;
 	}
 
-	private Object convertIfNecessary(String propertyName, Object oldValue, Object newValue, Class<?> requiredType,
+	private Object convertIfNecessary(@Nullable String propertyName, @Nullable Object oldValue, Object newValue, Class<?> requiredType,
 			TypeDescriptor td) throws TypeMismatchException {
 		try {
 			return this.typeConverterDelegate.convertIfNecessary(propertyName, oldValue, newValue, requiredType, td);
@@ -594,7 +594,7 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 		}
 	}
 
-	protected Object convertForProperty(String propertyName, Object oldValue, Object newValue, TypeDescriptor td)
+	protected Object convertForProperty(String propertyName, @Nullable Object oldValue, Object newValue, TypeDescriptor td)
 			throws TypeMismatchException {
 
 		return convertIfNecessary(propertyName, oldValue, newValue, td.getType(), td);
@@ -886,7 +886,7 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 		return new PropertyValue(tokens.canonicalName, defaultValue);
 	}
 
-	private Object newValue(Class<?> type, TypeDescriptor desc, String name) {
+	private Object newValue(Class<?> type, @Nullable TypeDescriptor desc, String name) {
 		try {
 			if (type.isArray()) {
 				Class<?> componentType = type.getComponentType();

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

@@ -599,7 +599,7 @@ public abstract class BeanUtils {
 	 * @throws BeansException if the copying failed
 	 * @see BeanWrapper
 	 */
-	private static void copyProperties(Object source, Object target, Class<?> editable, String... ignoreProperties)
+	private static void copyProperties(Object source, Object target, @Nullable Class<?> editable, String... ignoreProperties)
 			throws BeansException {
 
 		Assert.notNull(source, "Source must not be null");

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

@@ -28,6 +28,7 @@ import java.security.PrivilegedExceptionAction;
 import org.springframework.core.ResolvableType;
 import org.springframework.core.convert.Property;
 import org.springframework.core.convert.TypeDescriptor;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -147,7 +148,7 @@ public class BeanWrapperImpl extends AbstractNestablePropertyAccessor implements
 	}
 
 	@Override
-	public void setWrappedInstance(Object object, String nestedPath, Object rootObject) {
+	public void setWrappedInstance(Object object, String nestedPath, @Nullable Object rootObject) {
 		super.setWrappedInstance(object, nestedPath, rootObject);
 		setIntrospectionClass(getWrappedClass());
 	}

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

@@ -280,7 +280,7 @@ class ExtendedBeanInfo implements BeanInfo {
 			PropertyDescriptorUtils.copyNonMethodProperties(original, this);
 		}
 
-		public SimplePropertyDescriptor(String propertyName, Method readMethod, Method writeMethod) throws IntrospectionException {
+		public SimplePropertyDescriptor(String propertyName, @Nullable Method readMethod, Method writeMethod) throws IntrospectionException {
 			super(propertyName, null, null);
 			this.readMethod = readMethod;
 			this.writeMethod = writeMethod;
@@ -371,8 +371,8 @@ class ExtendedBeanInfo implements BeanInfo {
 			PropertyDescriptorUtils.copyNonMethodProperties(original, this);
 		}
 
-		public SimpleIndexedPropertyDescriptor(String propertyName, Method readMethod, Method writeMethod,
-				Method indexedReadMethod, Method indexedWriteMethod) throws IntrospectionException {
+		public SimpleIndexedPropertyDescriptor(String propertyName, @Nullable Method readMethod, @Nullable Method writeMethod,
+				@Nullable Method indexedReadMethod, Method indexedWriteMethod) throws IntrospectionException {
 
 			super(propertyName, null, null, null, null);
 			this.readMethod = readMethod;

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

@@ -145,7 +145,7 @@ class TypeConverterDelegate {
 	 * @throws IllegalArgumentException if type conversion failed
 	 */
 	@SuppressWarnings("unchecked")
-	public <T> T convertIfNecessary(String propertyName, @Nullable Object oldValue, Object newValue,
+	public <T> T convertIfNecessary(@Nullable String propertyName, @Nullable Object oldValue, Object newValue,
 			@Nullable Class<T> requiredType, TypeDescriptor typeDescriptor) throws IllegalArgumentException {
 
 		// Custom editor for this type?

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

@@ -339,7 +339,7 @@ public interface AutowireCapableBeanFactory extends BeanFactory {
 	 * @see #resolveDependency(DependencyDescriptor, String, Set, TypeConverter)
 	 */
 	@Nullable
-	Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName) throws BeansException;
+	Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName) throws BeansException;
 
 	/**
 	 * Resolve the specified dependency against the beans defined in this factory.
@@ -357,6 +357,6 @@ public interface AutowireCapableBeanFactory extends BeanFactory {
 	 */
 	@Nullable
 	Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName,
-			Set<String> autowiredBeanNames, TypeConverter typeConverter) throws BeansException;
+			@Nullable Set<String> autowiredBeanNames, @Nullable TypeConverter typeConverter) throws BeansException;
 
 }

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

@@ -32,7 +32,7 @@ public class BeanExpressionContext {
 	private final Scope scope;
 
 
-	public BeanExpressionContext(ConfigurableBeanFactory beanFactory, Scope scope) {
+	public BeanExpressionContext(ConfigurableBeanFactory beanFactory, @Nullable Scope scope) {
 		Assert.notNull(beanFactory, "BeanFactory must not be null");
 		this.beanFactory = beanFactory;
 		this.scope = scope;

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

@@ -102,7 +102,7 @@ public interface ConfigurableBeanFactory extends HierarchicalBeanFactory, Single
 	 * then removed once the BeanFactory completes its bootstrap phase.
 	 * @since 2.5
 	 */
-	void setTempClassLoader(ClassLoader tempClassLoader);
+	void setTempClassLoader(@Nullable ClassLoader tempClassLoader);
 
 	/**
 	 * Return the temporary ClassLoader to use for type matching purposes,

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

@@ -279,7 +279,7 @@ public class ConstructorArgumentValues {
 	 * @return the ValueHolder for the argument, or {@code null} if none found
 	 */
 	@Nullable
-	public ValueHolder getGenericArgumentValue(@Nullable Class<?> requiredType, @Nullable String requiredName, Set<ValueHolder> usedValueHolders) {
+	public ValueHolder getGenericArgumentValue(@Nullable Class<?> requiredType, @Nullable String requiredName, @Nullable Set<ValueHolder> usedValueHolders) {
 		for (ValueHolder valueHolder : this.genericArgumentValues) {
 			if (usedValueHolders != null && usedValueHolders.contains(valueHolder)) {
 				continue;
@@ -351,7 +351,7 @@ public class ConstructorArgumentValues {
 	 * @return the ValueHolder for the argument, or {@code null} if none set
 	 */
 	@Nullable
-	public ValueHolder getArgumentValue(int index, @Nullable Class<?> requiredType, @Nullable String requiredName, Set<ValueHolder> usedValueHolders) {
+	public ValueHolder getArgumentValue(int index, @Nullable Class<?> requiredType, @Nullable String requiredName, @Nullable Set<ValueHolder> usedValueHolders) {
 		Assert.isTrue(index >= 0, "Index must not be negative");
 		ValueHolder valueHolder = getIndexedArgumentValue(index, requiredType, requiredName);
 		if (valueHolder == null) {

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

@@ -52,7 +52,7 @@ public class TypedStringValue implements BeanMetadataElement {
 	 * Create a new {@link TypedStringValue} for the given String value.
 	 * @param value the String value
 	 */
-	public TypedStringValue(String value) {
+	public TypedStringValue(@Nullable String value) {
 		setValue(value);
 	}
 
@@ -62,7 +62,7 @@ public class TypedStringValue implements BeanMetadataElement {
 	 * @param value the String value
 	 * @param targetType the type to convert to
 	 */
-	public TypedStringValue(String value, Class<?> targetType) {
+	public TypedStringValue(@Nullable String value, Class<?> targetType) {
 		setValue(value);
 		setTargetType(targetType);
 	}
@@ -73,7 +73,7 @@ public class TypedStringValue implements BeanMetadataElement {
 	 * @param value the String value
 	 * @param targetTypeName the type to convert to
 	 */
-	public TypedStringValue(String value, String targetTypeName) {
+	public TypedStringValue(@Nullable String value, String targetTypeName) {
 		setValue(value);
 		setTargetTypeName(targetTypeName);
 	}
@@ -85,13 +85,14 @@ public class TypedStringValue implements BeanMetadataElement {
 	 * for example in BeanFactoryPostProcessors.
 	 * @see PropertyPlaceholderConfigurer
 	 */
-	public void setValue(String value) {
+	public void setValue(@Nullable String value) {
 		this.value = value;
 	}
 
 	/**
 	 * Return the String value.
 	 */
+	@Nullable
 	public String getValue() {
 		return this.value;
 	}

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

@@ -39,6 +39,7 @@ import org.yaml.snakeyaml.reader.UnicodeReader;
 
 import org.springframework.core.CollectionFactory;
 import org.springframework.core.io.Resource;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -272,7 +273,7 @@ public abstract class YamlProcessor {
 		return result;
 	}
 
-	private void buildFlattenedMap(Map<String, Object> result, Map<String, Object> source, String path) {
+	private void buildFlattenedMap(Map<String, Object> result, Map<String, Object> source, @Nullable String path) {
 		for (Entry<String, Object> entry : source.entrySet()) {
 			String key = entry.getKey();
 			if (StringUtils.hasText(path)) {

spring-beans/src/main/java/org/springframework/beans/factory/parsing/Problem.java

@@ -67,7 +67,7 @@ public class Problem {
 	 * @param parseState the {@link ParseState} at the time of the error
 	 * @param location the location within a bean configuration source that triggered the error
 	 */
-	public Problem(String message, Location location, ParseState parseState, @Nullable Throwable rootCause) {
+	public Problem(String message, Location location, @Nullable ParseState parseState, @Nullable Throwable rootCause) {
 		Assert.notNull(message, "Message must not be null");
 		Assert.notNull(location, "Location must not be null");
 		this.message = message;

spring-beans/src/main/java/org/springframework/beans/factory/parsing/ReaderContext.java

@@ -17,6 +17,7 @@
 package org.springframework.beans.factory.parsing;
 
 import org.springframework.core.io.Resource;
+import org.springframework.lang.Nullable;
 
 /**
  * Context that gets passed along a bean definition reading process,
@@ -59,11 +60,11 @@ public class ReaderContext {
 		fatal(message, source, null, ex);
 	}
 
-	public void fatal(String message, Object source, ParseState parseState) {
+	public void fatal(String message, Object source, @Nullable ParseState parseState) {
 		fatal(message, source, parseState, null);
 	}
 
-	public void fatal(String message, Object source, ParseState parseState, Throwable cause) {
+	public void fatal(String message, Object source, @Nullable ParseState parseState, @Nullable Throwable cause) {
 		Location location = new Location(getResource(), source);
 		this.problemReporter.fatal(new Problem(message, location, parseState, cause));
 	}
@@ -72,15 +73,15 @@ public class ReaderContext {
 		error(message, source, null, null);
 	}
 
-	public void error(String message, Object source, Throwable ex) {
+	public void error(String message, Object source, @Nullable Throwable ex) {
 		error(message, source, null, ex);
 	}
 
-	public void error(String message, Object source, ParseState parseState) {
+	public void error(String message, Object source, @Nullable ParseState parseState) {
 		error(message, source, parseState, null);
 	}
 
-	public void error(String message, Object source, ParseState parseState, Throwable cause) {
+	public void error(String message, Object source, @Nullable ParseState parseState, @Nullable Throwable cause) {
 		Location location = new Location(getResource(), source);
 		this.problemReporter.error(new Problem(message, location, parseState, cause));
 	}
@@ -89,15 +90,15 @@ public class ReaderContext {
 		warning(message, source, null, null);
 	}
 
-	public void warning(String message, Object source, Throwable ex) {
+	public void warning(String message, Object source, @Nullable Throwable ex) {
 		warning(message, source, null, ex);
 	}
 
-	public void warning(String message, Object source, ParseState parseState) {
+	public void warning(String message, Object source, @Nullable ParseState parseState) {
 		warning(message, source, parseState, null);
 	}
 
-	public void warning(String message, Object source, ParseState parseState, Throwable cause) {
+	public void warning(String message, Object source, @Nullable ParseState parseState, @Nullable Throwable cause) {
 		Location location = new Location(getResource(), source);
 		this.problemReporter.warning(new Problem(message, location, parseState, cause));
 	}

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

@@ -334,7 +334,7 @@ public abstract class AbstractAutowireCapableBeanFactory extends AbstractBeanFac
 	}
 
 	@Override
-	public Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName) throws BeansException {
+	public Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName) throws BeansException {
 		return resolveDependency(descriptor, requestingBeanName, null, null);
 	}
 
@@ -452,7 +452,7 @@ public abstract class AbstractAutowireCapableBeanFactory extends AbstractBeanFac
 	 * @see #doCreateBean
 	 */
 	@Override
-	protected Object createBean(String beanName, RootBeanDefinition mbd, Object[] args) throws BeanCreationException {
+	protected Object createBean(String beanName, RootBeanDefinition mbd, @Nullable Object[] args) throws BeanCreationException {
 		if (logger.isDebugEnabled()) {
 			logger.debug("Creating instance of bean '" + beanName + "'");
 		}
@@ -1084,7 +1084,7 @@ public abstract class AbstractAutowireCapableBeanFactory extends AbstractBeanFac
 	 * @see #autowireConstructor
 	 * @see #instantiateBean
 	 */
-	protected BeanWrapper createBeanInstance(String beanName, RootBeanDefinition mbd, Object[] args) {
+	protected BeanWrapper createBeanInstance(String beanName, RootBeanDefinition mbd, @Nullable Object[] args) {
 		// Make sure bean class is actually resolved at this point.
 		Class<?> beanClass = resolveBeanClass(mbd, beanName);
 
@@ -1271,7 +1271,7 @@ public abstract class AbstractAutowireCapableBeanFactory extends AbstractBeanFac
 	 * @return a BeanWrapper for the new instance
 	 */
 	protected BeanWrapper autowireConstructor(
-			String beanName, RootBeanDefinition mbd, Constructor<?>[] ctors, @Nullable Object[] explicitArgs) {
+			String beanName, RootBeanDefinition mbd, @Nullable Constructor<?>[] ctors, @Nullable Object[] explicitArgs) {
 
 		return new ConstructorResolver(this).autowireConstructor(beanName, mbd, ctors, explicitArgs);
 	}

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

@@ -230,7 +230,7 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 	 */
 	@SuppressWarnings("unchecked")
 	protected <T> T doGetBean(
-			final String name, final Class<T> requiredType, final Object[] args, boolean typeCheckOnly)
+			final String name, @Nullable final Class<T> requiredType, @Nullable final Object[] args, boolean typeCheckOnly)
 			throws BeansException {
 
 		final String beanName = transformedBeanName(name);
@@ -708,7 +708,7 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 	}
 
 	@Override
-	public void setTempClassLoader(ClassLoader tempClassLoader) {
+	public void setTempClassLoader(@Nullable ClassLoader tempClassLoader) {
 		this.tempClassLoader = tempClassLoader;
 	}
 

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

@@ -20,6 +20,7 @@ import java.util.function.Supplier;
 
 import org.springframework.beans.factory.config.BeanDefinitionCustomizer;
 import org.springframework.beans.factory.config.RuntimeBeanReference;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ObjectUtils;
 
 /**
@@ -93,7 +94,7 @@ public class BeanDefinitionBuilder {
 	 * @param beanClassName the class name for the bean that the definition is being created for
 	 * @param factoryMethodName the name of the method to use to construct the bean instance
 	 */
-	public static BeanDefinitionBuilder rootBeanDefinition(String beanClassName, String factoryMethodName) {
+	public static BeanDefinitionBuilder rootBeanDefinition(String beanClassName, @Nullable String factoryMethodName) {
 		BeanDefinitionBuilder builder = new BeanDefinitionBuilder();
 		builder.beanDefinition = new RootBeanDefinition();
 		builder.beanDefinition.setBeanClassName(beanClassName);
@@ -114,7 +115,7 @@ public class BeanDefinitionBuilder {
 	 * @param beanClass the {@code Class} of the bean that the definition is being created for
 	 * @param factoryMethodName the name of the method to use to construct the bean instance
 	 */
-	public static BeanDefinitionBuilder rootBeanDefinition(Class<?> beanClass, String factoryMethodName) {
+	public static BeanDefinitionBuilder rootBeanDefinition(Class<?> beanClass, @Nullable String factoryMethodName) {
 		BeanDefinitionBuilder builder = new BeanDefinitionBuilder();
 		builder.beanDefinition = new RootBeanDefinition();
 		builder.beanDefinition.setBeanClass(beanClass);

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

@@ -78,7 +78,7 @@ public class CglibSubclassingInstantiationStrategy extends SimpleInstantiationSt
 
 	@Override
 	protected Object instantiateWithMethodInjection(RootBeanDefinition bd, String beanName, BeanFactory owner,
-			Constructor<?> ctor, Object... args) {
+			@Nullable Constructor<?> ctor, Object... args) {
 
 		// Must generate CGLIB subclass...
 		return new CglibSubclassCreator(bd, owner).instantiate(ctor, args);

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

@@ -823,7 +823,7 @@ class ConstructorResolver {
 	 * Template method for resolving the specified argument which is supposed to be autowired.
 	 */
 	protected Object resolveAutowiredArgument(
-			MethodParameter param, String beanName, Set<String> autowiredBeanNames, TypeConverter typeConverter) {
+			MethodParameter param, String beanName, @Nullable Set<String> autowiredBeanNames, TypeConverter typeConverter) {
 
 		if (InjectionPoint.class.isAssignableFrom(param.getParameterType())) {
 			InjectionPoint injectionPoint = currentInjectionPoint.get();

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

@@ -1040,7 +1040,7 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 
 	@Override
 	public Object resolveDependency(DependencyDescriptor descriptor, String requestingBeanName,
-			Set<String> autowiredBeanNames, TypeConverter typeConverter) throws BeansException {
+			@Nullable Set<String> autowiredBeanNames, @Nullable TypeConverter typeConverter) throws BeansException {
 
 		descriptor.initParameterNameDiscovery(getParameterNameDiscoverer());
 		if (Optional.class == descriptor.getDependencyType()) {
@@ -1065,7 +1065,7 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 
 	@Nullable
 	public Object doResolveDependency(DependencyDescriptor descriptor, String beanName,
-			Set<String> autowiredBeanNames, TypeConverter typeConverter) throws BeansException {
+			@Nullable Set<String> autowiredBeanNames, @Nullable TypeConverter typeConverter) throws BeansException {
 
 		InjectionPoint previousInjectionPoint = ConstructorResolver.setCurrentInjectionPoint(descriptor);
 		try {

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

@@ -450,7 +450,7 @@ public class DefaultSingletonBeanRegistry extends SimpleAliasRegistry implements
 		return isDependent(beanName, dependentBeanName, null);
 	}
 
-	private boolean isDependent(String beanName, String dependentBeanName, Set<String> alreadySeen) {
+	private boolean isDependent(String beanName, String dependentBeanName, @Nullable Set<String> alreadySeen) {
 		if (alreadySeen != null && alreadySeen.contains(beanName)) {
 			return false;
 		}

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

@@ -178,7 +178,7 @@ public class RootBeanDefinition extends AbstractBeanDefinition {
 	 * @param cargs the constructor argument values to apply
 	 * @param pvs the property values to apply
 	 */
-	public RootBeanDefinition(@Nullable Class<?> beanClass, ConstructorArgumentValues cargs, MutablePropertyValues pvs) {
+	public RootBeanDefinition(@Nullable Class<?> beanClass, ConstructorArgumentValues cargs, @Nullable MutablePropertyValues pvs) {
 		super(cargs, pvs);
 		setBeanClass(beanClass);
 	}

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

@@ -135,7 +135,7 @@ public class SimpleInstantiationStrategy implements InstantiationStrategy {
 	 * Instantiation should use the given constructor and parameters.
 	 */
 	protected Object instantiateWithMethodInjection(RootBeanDefinition bd, String beanName, BeanFactory owner,
-			Constructor<?> ctor, Object... args) {
+			@Nullable Constructor<?> ctor, Object... args) {
 
 		throw new UnsupportedOperationException("Method Injection not supported in SimpleInstantiationStrategy");
 	}

spring-beans/src/main/java/org/springframework/beans/factory/xml/BeanDefinitionParserDelegate.java

@@ -309,7 +309,7 @@ public class BeanDefinitionParserDelegate {
 	 * @see #populateDefaults(DocumentDefaultsDefinition, DocumentDefaultsDefinition, org.w3c.dom.Element)
 	 * @see #getDefaults()
 	 */
-	public void initDefaults(Element root, BeanDefinitionParserDelegate parent) {
+	public void initDefaults(Element root, @Nullable BeanDefinitionParserDelegate parent) {
 		populateDefaults(this.defaults, (parent != null ? parent.defaults : null), root);
 		this.readerContext.fireDefaultsRegistered(this.defaults);
 	}
@@ -417,7 +417,7 @@ public class BeanDefinitionParserDelegate {
 	 * {@link org.springframework.beans.factory.parsing.ProblemReporter}.
 	 */
 	@Nullable
-	public BeanDefinitionHolder parseBeanDefinitionElement(Element ele, BeanDefinition containingBean) {
+	public BeanDefinitionHolder parseBeanDefinitionElement(Element ele, @Nullable BeanDefinition containingBean) {
 		String id = ele.getAttribute(ID_ATTRIBUTE);
 		String nameAttr = ele.getAttribute(NAME_ATTRIBUTE);
 
@@ -907,7 +907,7 @@ public class BeanDefinitionParserDelegate {
 	 * Also used for constructor arguments, "propertyName" being null in this case.
 	 */
 	@Nullable
-	public Object parsePropertyValue(Element ele, BeanDefinition bd, String propertyName) {
+	public Object parsePropertyValue(Element ele, BeanDefinition bd, @Nullable String propertyName) {
 		String elementName = (propertyName != null) ?
 						"<property> element for property '" + propertyName + "'" :
 						"<constructor-arg> element";
@@ -961,7 +961,7 @@ public class BeanDefinitionParserDelegate {
 		}
 	}
 
-	public Object parsePropertySubElement(Element ele, BeanDefinition bd) {
+	public Object parsePropertySubElement(Element ele, @Nullable BeanDefinition bd) {
 		return parsePropertySubElement(ele, bd, null);
 	}
 
@@ -973,7 +973,7 @@ public class BeanDefinitionParserDelegate {
 	 * {@code <value>} tag that might be created
 	 */
 	@Nullable
-	public Object parsePropertySubElement(Element ele, BeanDefinition bd, String defaultValueType) {
+	public Object parsePropertySubElement(Element ele, BeanDefinition bd, @Nullable String defaultValueType) {
 		if (!isDefaultNamespace(ele)) {
 			return parseNestedCustomElement(ele, bd);
 		}
@@ -1355,7 +1355,7 @@ public class BeanDefinitionParserDelegate {
 	}
 
 	@Nullable
-	public BeanDefinition parseCustomElement(Element ele, BeanDefinition containingBd) {
+	public BeanDefinition parseCustomElement(Element ele, @Nullable BeanDefinition containingBd) {
 		String namespaceUri = getNamespaceURI(ele);
 		NamespaceHandler handler = this.readerContext.getNamespaceHandlerResolver().resolve(namespaceUri);
 		if (handler == null) {
@@ -1370,7 +1370,7 @@ public class BeanDefinitionParserDelegate {
 	}
 
 	public BeanDefinitionHolder decorateBeanDefinitionIfRequired(
-			Element ele, BeanDefinitionHolder definitionHolder, BeanDefinition containingBd) {
+			Element ele, BeanDefinitionHolder definitionHolder, @Nullable BeanDefinition containingBd) {
 
 		BeanDefinitionHolder finalDefinition = definitionHolder;
 

spring-context-support/src/main/java/org/springframework/mail/javamail/JavaMailSenderImpl.java

@@ -404,7 +404,7 @@ public class JavaMailSenderImpl implements JavaMailSender {
 	 * @throws org.springframework.mail.MailSendException
 	 * in case of failure when sending a message
 	 */
-	protected void doSend(MimeMessage[] mimeMessages, Object[] originalMessages) throws MailException {
+	protected void doSend(MimeMessage[] mimeMessages, @Nullable Object[] originalMessages) throws MailException {
 		Map<Object, Exception> failedMessages = new LinkedHashMap<>();
 		Transport transport = null;
 

spring-context-support/src/main/java/org/springframework/mail/javamail/MimeMessageHelper.java

@@ -362,7 +362,7 @@ public class MimeMessageHelper {
 	 * will be added to (can be the same as the root multipart object, or an element
 	 * nested underneath the root multipart element)
 	 */
-	protected final void setMimeMultiparts(@Nullable MimeMultipart root, MimeMultipart main) {
+	protected final void setMimeMultiparts(@Nullable MimeMultipart root, @Nullable MimeMultipart main) {
 		this.rootMimeMultipart = root;
 		this.mimeMultipart = main;
 	}

spring-context-support/src/main/java/org/springframework/scheduling/quartz/SchedulerAccessor.java

@@ -39,6 +39,7 @@ import org.quartz.xml.XMLSchedulingDataProcessor;
 
 import org.springframework.context.ResourceLoaderAware;
 import org.springframework.core.io.ResourceLoader;
+import org.springframework.lang.Nullable;
 import org.springframework.transaction.PlatformTransactionManager;
 import org.springframework.transaction.TransactionException;
 import org.springframework.transaction.TransactionStatus;
@@ -186,7 +187,7 @@ public abstract class SchedulerAccessor implements ResourceLoaderAware {
 	}
 
 	@Override
-	public void setResourceLoader(ResourceLoader resourceLoader) {
+	public void setResourceLoader(@Nullable ResourceLoader resourceLoader) {
 		this.resourceLoader = resourceLoader;
 	}
 

spring-context/src/main/java/org/springframework/cache/interceptor/CacheAspectSupport.java

@@ -458,7 +458,7 @@ public abstract class CacheAspectSupport extends AbstractCacheInvoker
 		}
 	}
 
-	private void logInvalidating(CacheOperationContext context, CacheEvictOperation operation, Object key) {
+	private void logInvalidating(CacheOperationContext context, CacheEvictOperation operation, @Nullable Object key) {
 		if (logger.isTraceEnabled()) {
 			logger.trace("Invalidating " + (key != null ? "cache key [" + key + "]" : "entire cache") +
 					" for operation " + operation + " on method " + context.metadata.method);

spring-context/src/main/java/org/springframework/context/MessageSource.java

@@ -53,7 +53,7 @@ public interface MessageSource {
 	 * otherwise the default message passed as a parameter
 	 * @see java.text.MessageFormat
 	 */
-	String getMessage(String code, @Nullable Object[] args, String defaultMessage, Locale locale);
+	String getMessage(String code, @Nullable Object[] args, @Nullable String defaultMessage, Locale locale);
 
 	/**
 	 * Try to resolve the message. Treat as an error if the message can't be found.

spring-context/src/main/java/org/springframework/context/ResourceLoaderAware.java

@@ -18,6 +18,7 @@ package org.springframework.context;
 
 import org.springframework.beans.factory.Aware;
 import org.springframework.core.io.ResourceLoader;
+import org.springframework.lang.Nullable;
 
 /**
  * Interface to be implemented by any object that wishes to be notified of
@@ -73,6 +74,6 @@ public interface ResourceLoaderAware extends Aware {
 	 * @see org.springframework.core.io.support.ResourcePatternResolver
 	 * @see org.springframework.core.io.support.ResourcePatternUtils#getResourcePatternResolver
 	 */
-	void setResourceLoader(ResourceLoader resourceLoader);
+	void setResourceLoader(@Nullable ResourceLoader resourceLoader);
 
 }

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

@@ -210,7 +210,7 @@ public class AnnotatedBeanDefinitionReader {
 	 * factory's {@link BeanDefinition}, e.g. setting a lazy-init or primary flag
 	 * @since 5.0
 	 */
-	<T> void doRegisterBean(Class<T> annotatedClass, @Nullable Supplier<T> instanceSupplier, String name,
+	<T> void doRegisterBean(Class<T> annotatedClass, @Nullable Supplier<T> instanceSupplier, @Nullable String name,
 			@Nullable Class<? extends Annotation>[] qualifiers, BeanDefinitionCustomizer... definitionCustomizers) {
 
 		AnnotatedGenericBeanDefinition abd = new AnnotatedGenericBeanDefinition(annotatedClass);

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

@@ -214,7 +214,7 @@ public class AnnotationConfigApplicationContext extends GenericApplicationContex
 	}
 
 	@Override
-	public <T> void registerBean(@Nullable String beanName, @Nullable Class<T> beanClass, Supplier<T> supplier,
+	public <T> void registerBean(@Nullable String beanName, @Nullable Class<T> beanClass, @Nullable Supplier<T> supplier,
 			BeanDefinitionCustomizer... customizers) {
 
 		this.reader.doRegisterBean(beanClass, supplier, beanName, null, customizers);

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

@@ -252,7 +252,7 @@ public class ClassPathScanningCandidateComponentProvider implements EnvironmentC
 	 * @see org.springframework.core.io.support.PathMatchingResourcePatternResolver
 	 */
 	@Override
-	public void setResourceLoader(ResourceLoader resourceLoader) {
+	public void setResourceLoader(@Nullable ResourceLoader resourceLoader) {
 		this.resourcePatternResolver = ResourcePatternUtils.getResourcePatternResolver(resourceLoader);
 		this.metadataReaderFactory = new CachingMetadataReaderFactory(resourceLoader);
 		this.componentsIndex = CandidateComponentsIndexLoader.loadIndex(this.resourcePatternResolver.getClassLoader());

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

@@ -193,7 +193,7 @@ public class ConfigurationClassPostProcessor implements BeanDefinitionRegistryPo
 	}
 
 	@Override
-	public void setResourceLoader(ResourceLoader resourceLoader) {
+	public void setResourceLoader(@Nullable ResourceLoader resourceLoader) {
 		Assert.notNull(resourceLoader, "ResourceLoader must not be null");
 		this.resourceLoader = resourceLoader;
 		if (!this.setMetadataReaderFactoryCalled) {

spring-context/src/main/java/org/springframework/context/event/AbstractApplicationEventMulticaster.java

@@ -208,7 +208,7 @@ public abstract class AbstractApplicationEventMulticaster
 	 * @return the pre-filtered list of application listeners for the given event and source type
 	 */
 	private Collection<ApplicationListener<?>> retrieveApplicationListeners(
-			ResolvableType eventType, Class<?> sourceType, ListenerRetriever retriever) {
+			ResolvableType eventType, Class<?> sourceType, @Nullable ListenerRetriever retriever) {
 
 		LinkedList<ApplicationListener<?>> allListeners = new LinkedList<>();
 		Set<ApplicationListener<?>> listeners;

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

@@ -367,7 +367,7 @@ public abstract class AbstractApplicationContext extends DefaultResourceLoader
 	 * @param eventType the resolved event type, if known
 	 * @since 4.2
 	 */
-	protected void publishEvent(Object event, ResolvableType eventType) {
+	protected void publishEvent(Object event, @Nullable ResolvableType eventType) {
 		Assert.notNull(event, "Event must not be null");
 		if (logger.isTraceEnabled()) {
 			logger.trace("Publishing event in " + getDisplayName() + ": " + event);
@@ -1250,7 +1250,7 @@ public abstract class AbstractApplicationContext extends DefaultResourceLoader
 	//---------------------------------------------------------------------
 
 	@Override
-	public String getMessage(String code, @Nullable Object args[], String defaultMessage, Locale locale) {
+	public String getMessage(String code, @Nullable Object args[], @Nullable String defaultMessage, Locale locale) {
 		return getMessageSource().getMessage(code, args, defaultMessage, locale);
 	}
 

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

@@ -134,7 +134,7 @@ public abstract class AbstractMessageSource extends MessageSourceSupport impleme
 
 
 	@Override
-	public final String getMessage(String code, @Nullable Object[] args, String defaultMessage, Locale locale) {
+	public final String getMessage(String code, @Nullable Object[] args, @Nullable String defaultMessage, Locale locale) {
 		String msg = getMessageInternal(code, args, locale);
 		if (msg != null) {
 			return msg;

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

@@ -52,7 +52,7 @@ public class DelegatingMessageSource extends MessageSourceSupport implements Hie
 
 
 	@Override
-	public String getMessage(String code, @Nullable Object[] args, String defaultMessage, Locale locale) {
+	public String getMessage(String code, @Nullable Object[] args, @Nullable String defaultMessage, Locale locale) {
 		if (this.parentMessageSource != null) {
 			return this.parentMessageSource.getMessage(code, args, defaultMessage, locale);
 		}

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

@@ -419,7 +419,7 @@ public class GenericApplicationContext extends AbstractApplicationContext implem
 	 * factory's {@link BeanDefinition}, e.g. setting a lazy-init or primary flag
 	 * @since 5.0
 	 */
-	public <T> void registerBean(@Nullable String beanName, @Nullable Class<T> beanClass, Supplier<T> supplier,
+	public <T> void registerBean(@Nullable String beanName, @Nullable Class<T> beanClass, @Nullable Supplier<T> supplier,
 			BeanDefinitionCustomizer... customizers) {
 
 		Assert.isTrue(beanName != null || beanClass != null, "Either bean name or bean class must be specified");

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

@@ -162,7 +162,7 @@ public class ReloadableResourceBundleMessageSource extends AbstractResourceBased
 	 * @see org.springframework.context.ResourceLoaderAware
 	 */
 	@Override
-	public void setResourceLoader(ResourceLoader resourceLoader) {
+	public void setResourceLoader(@Nullable ResourceLoader resourceLoader) {
 		this.resourceLoader = (resourceLoader != null ? resourceLoader : new DefaultResourceLoader());
 	}
 

spring-context/src/main/java/org/springframework/instrument/classloading/WeavingTransformer.java

@@ -22,6 +22,8 @@ import java.security.ProtectionDomain;
 import java.util.ArrayList;
 import java.util.List;
 
+import org.springframework.lang.Nullable;
+
 /**
  * ClassFileTransformer-based weaver, allowing for a list of transformers to be
  * applied on a class byte array. Normally used inside class loaders.
@@ -88,7 +90,7 @@ public class WeavingTransformer {
 	 * @param pd protection domain to be used (can be null)
 	 * @return (possibly transformed) class byte definition
 	 */
-	public byte[] transformIfNecessary(String className, String internalName, byte[] bytes, ProtectionDomain pd) {
+	public byte[] transformIfNecessary(String className, String internalName, byte[] bytes, @Nullable ProtectionDomain pd) {
 		byte[] result = bytes;
 		for (ClassFileTransformer cft : this.transformers) {
 			try {

spring-context/src/main/java/org/springframework/jmx/export/MBeanExporter.java

@@ -749,7 +749,7 @@ public class MBeanExporter extends MBeanRegistrationSupport implements MBeanExpo
 	 * @throws javax.management.MalformedObjectNameException
 	 * if the retrieved {@code ObjectName} is malformed
 	 */
-	protected ObjectName getObjectName(Object bean, String beanKey) throws MalformedObjectNameException {
+	protected ObjectName getObjectName(Object bean, @Nullable String beanKey) throws MalformedObjectNameException {
 		if (bean instanceof SelfNaming) {
 			return ((SelfNaming) bean).getObjectName();
 		}

spring-context/src/main/java/org/springframework/jndi/JndiLocatorDelegate.java

@@ -20,6 +20,7 @@ import javax.naming.InitialContext;
 import javax.naming.NamingException;
 
 import org.springframework.core.SpringProperties;
+import org.springframework.lang.Nullable;
 
 /**
  * {@link JndiLocatorSupport} subclass with public lookup methods,
@@ -59,7 +60,7 @@ public class JndiLocatorDelegate extends JndiLocatorSupport {
 	}
 
 	@Override
-	public <T> T lookup(String jndiName, Class<T> requiredType) throws NamingException {
+	public <T> T lookup(String jndiName, @Nullable Class<T> requiredType) throws NamingException {
 		return super.lookup(jndiName, requiredType);
 	}
 

spring-context/src/main/java/org/springframework/jndi/JndiLocatorSupport.java

@@ -18,6 +18,7 @@ package org.springframework.jndi;
 
 import javax.naming.NamingException;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -87,7 +88,7 @@ public abstract class JndiLocatorSupport extends JndiAccessor {
 	 * @throws NamingException if the JNDI lookup failed
 	 * @see #setResourceRef
 	 */
-	protected <T> T lookup(String jndiName, Class<T> requiredType) throws NamingException {
+	protected <T> T lookup(String jndiName, @Nullable Class<T> requiredType) throws NamingException {
 		Assert.notNull(jndiName, "'jndiName' must not be null");
 		String convertedName = convertJndiName(jndiName);
 		T jndiObject;

spring-context/src/main/java/org/springframework/jndi/support/SimpleJndiBeanFactory.java

@@ -206,7 +206,7 @@ public class SimpleJndiBeanFactory extends JndiLocatorSupport implements BeanFac
 
 
 	@SuppressWarnings("unchecked")
-	private <T> T doGetSingleton(String name, Class<T> requiredType) throws NamingException {
+	private <T> T doGetSingleton(String name, @Nullable Class<T> requiredType) throws NamingException {
 		synchronized (this.singletonObjects) {
 			if (this.singletonObjects.containsKey(name)) {
 				Object jndiObject = this.singletonObjects.get(name);

spring-context/src/main/java/org/springframework/scheduling/annotation/AsyncResult.java

@@ -20,6 +20,7 @@ import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.concurrent.FailureCallback;
 import org.springframework.util.concurrent.ListenableFuture;
 import org.springframework.util.concurrent.ListenableFutureCallback;
@@ -54,7 +55,7 @@ public class AsyncResult<V> implements ListenableFuture<V> {
 	 * Create a new AsyncResult holder.
 	 * @param value the value to pass through
 	 */
-	public AsyncResult(V value) {
+	public AsyncResult(@Nullable V value) {
 		this(value, null);
 	}
 
@@ -62,7 +63,7 @@ public class AsyncResult<V> implements ListenableFuture<V> {
 	 * Create a new AsyncResult holder.
 	 * @param value the value to pass through
 	 */
-	private AsyncResult(V value, ExecutionException ex) {
+	private AsyncResult(@Nullable V value, @Nullable ExecutionException ex) {
 		this.value = value;
 		this.executionException = ex;
 	}

spring-context/src/main/java/org/springframework/scheduling/concurrent/ConcurrentTaskExecutor.java

@@ -28,6 +28,7 @@ import javax.enterprise.concurrent.ManagedTask;
 import org.springframework.core.task.AsyncListenableTaskExecutor;
 import org.springframework.core.task.TaskDecorator;
 import org.springframework.core.task.support.TaskExecutorAdapter;
+import org.springframework.lang.Nullable;
 import org.springframework.scheduling.SchedulingAwareRunnable;
 import org.springframework.scheduling.SchedulingTaskExecutor;
 import org.springframework.util.ClassUtils;
@@ -105,7 +106,7 @@ public class ConcurrentTaskExecutor implements AsyncListenableTaskExecutor, Sche
 	 * <p>Autodetects a JSR-236 {@link javax.enterprise.concurrent.ManagedExecutorService}
 	 * in order to expose {@link javax.enterprise.concurrent.ManagedTask} adapters for it.
 	 */
-	public final void setConcurrentExecutor(Executor concurrentExecutor) {
+	public final void setConcurrentExecutor(@Nullable Executor concurrentExecutor) {
 		if (concurrentExecutor != null) {
 			this.concurrentExecutor = concurrentExecutor;
 			if (managedExecutorServiceClass != null && managedExecutorServiceClass.isInstance(concurrentExecutor)) {

spring-context/src/main/java/org/springframework/scripting/bsh/BshScriptUtils.java

@@ -85,7 +85,7 @@ public abstract class BshScriptUtils {
 	 * @return the scripted Java object
 	 * @throws EvalError in case of BeanShell parsing failure
 	 */
-	public static Object createBshObject(String scriptSource, @Nullable Class<?>[] scriptInterfaces, ClassLoader classLoader)
+	public static Object createBshObject(String scriptSource, @Nullable Class<?>[] scriptInterfaces, @Nullable ClassLoader classLoader)
 			throws EvalError {
 
 		Object result = evaluateBshScript(scriptSource, scriptInterfaces, classLoader);

spring-context/src/main/java/org/springframework/scripting/support/ScriptFactoryPostProcessor.java

@@ -228,7 +228,7 @@ public class ScriptFactoryPostProcessor extends InstantiationAwareBeanPostProces
 	}
 
 	@Override
-	public void setResourceLoader(ResourceLoader resourceLoader) {
+	public void setResourceLoader(@Nullable ResourceLoader resourceLoader) {
 		this.resourceLoader = resourceLoader;
 	}
 

spring-context/src/main/java/org/springframework/validation/AbstractBindingResult.java

@@ -92,7 +92,7 @@ public abstract class AbstractBindingResult extends AbstractErrors implements Bi
 
 
 	@Override
-	public void reject(String errorCode, @Nullable Object[] errorArgs, String defaultMessage) {
+	public void reject(String errorCode, @Nullable Object[] errorArgs, @Nullable String defaultMessage) {
 		addError(new ObjectError(getObjectName(), resolveMessageCodes(errorCode), errorArgs, defaultMessage));
 	}
 

spring-context/src/main/java/org/springframework/validation/BindException.java

@@ -115,7 +115,7 @@ public class BindException extends Exception implements BindingResult {
 	}
 
 	@Override
-	public void reject(String errorCode, @Nullable Object[] errorArgs, String defaultMessage) {
+	public void reject(String errorCode, @Nullable Object[] errorArgs, @Nullable String defaultMessage) {
 		this.bindingResult.reject(errorCode, errorArgs, defaultMessage);
 	}
 

spring-context/src/main/java/org/springframework/validation/DefaultMessageCodesResolver.java

@@ -164,13 +164,13 @@ public class DefaultMessageCodesResolver implements MessageCodesResolver, Serial
 		return StringUtils.toStringArray(codeList);
 	}
 
-	private void addCodes(Collection<String> codeList, String errorCode, String objectName, Iterable<String> fields) {
+	private void addCodes(Collection<String> codeList, String errorCode, @Nullable String objectName, Iterable<String> fields) {
 		for (String field : fields) {
 			addCode(codeList, errorCode, objectName, field);
 		}
 	}
 
-	private void addCode(Collection<String> codeList, String errorCode, String objectName, String field) {
+	private void addCode(Collection<String> codeList, String errorCode, @Nullable String objectName, @Nullable String field) {
 		codeList.add(postProcessMessageCode(this.formatter.format(errorCode, objectName, field)));
 	}
 

spring-context/src/main/java/org/springframework/validation/Errors.java

@@ -121,7 +121,7 @@ public interface Errors {
 	 * (can be {@code null})
 	 * @param defaultMessage fallback default message
 	 */
-	void reject(String errorCode, @Nullable Object[] errorArgs, String defaultMessage);
+	void reject(String errorCode, @Nullable Object[] errorArgs, @Nullable String defaultMessage);
 
 	/**
 	 * Register a field error for the specified field of the current object

spring-context/src/main/java/org/springframework/validation/ValidationUtils.java

@@ -160,7 +160,7 @@ public abstract class ValidationUtils {
 	 * @param defaultMessage fallback default message
 	 */
 	public static void rejectIfEmpty(
-			Errors errors, String field, String errorCode, @Nullable Object[] errorArgs, String defaultMessage) {
+			Errors errors, String field, String errorCode, @Nullable Object[] errorArgs, @Nullable String defaultMessage) {
 
 		Assert.notNull(errors, "Errors object must not be null");
 		Object value = errors.getFieldValue(field);
@@ -240,7 +240,7 @@ public abstract class ValidationUtils {
 	 * @param defaultMessage fallback default message
 	 */
 	public static void rejectIfEmptyOrWhitespace(
-			Errors errors, String field, String errorCode, @Nullable Object[] errorArgs, String defaultMessage) {
+			Errors errors, String field, String errorCode, @Nullable Object[] errorArgs, @Nullable String defaultMessage) {
 
 		Assert.notNull(errors, "Errors object must not be null");
 		Object value = errors.getFieldValue(field);

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

@@ -74,7 +74,7 @@ public class OrderComparator implements Comparator<Object> {
 		return doCompare(o1, o2, null);
 	}
 
-	private int doCompare(Object o1, Object o2, OrderSourceProvider sourceProvider) {
+	private int doCompare(Object o1, Object o2, @Nullable OrderSourceProvider sourceProvider) {
 		boolean p1 = (o1 instanceof PriorityOrdered);
 		boolean p2 = (o2 instanceof PriorityOrdered);
 		if (p1 && !p2) {

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

@@ -122,7 +122,7 @@ public class ReactiveAdapterRegistry {
 	 * (i.e. to adapt from; may be {@code null} if the reactive type is specified)
 	 */
 	@Nullable
-	public ReactiveAdapter getAdapter(@Nullable Class<?> reactiveType, Object source) {
+	public ReactiveAdapter getAdapter(@Nullable Class<?> reactiveType, @Nullable Object source) {
 
 		Object sourceToUse = (source instanceof Optional ? ((Optional<?>) source).orElse(null) : source);
 		Class<?> clazz = (sourceToUse != null ? sourceToUse.getClass() : reactiveType);

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

@@ -17,6 +17,7 @@ package org.springframework.core;
 
 import java.util.function.Supplier;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -42,7 +43,7 @@ public class ReactiveTypeDescriptor {
 	/**
 	 * Private constructor. See static factory methods.
 	 */
-	private ReactiveTypeDescriptor(Class<?> reactiveType, Supplier<?> emptySupplier,
+	private ReactiveTypeDescriptor(Class<?> reactiveType, @Nullable Supplier<?> emptySupplier,
 			boolean multiValue, boolean canBeEmpty, boolean noValue) {
 
 		Assert.notNull(reactiveType, "'reactiveType' must not be null");

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

@@ -146,7 +146,7 @@ public class ResolvableType implements Serializable {
 	 * with upfront resolution and a pre-calculated hash.
 	 * @since 4.2
 	 */
-	private ResolvableType(Type type, TypeProvider typeProvider, VariableResolver variableResolver, Integer hash) {
+	private ResolvableType(@Nullable Type type, @Nullable TypeProvider typeProvider, @Nullable VariableResolver variableResolver, Integer hash) {
 		this.type = type;
 		this.typeProvider = typeProvider;
 		this.variableResolver = variableResolver;
@@ -160,7 +160,7 @@ public class ResolvableType implements Serializable {
 	 * with upfront resolution but lazily calculated hash.
 	 */
 	private ResolvableType(
-			Type type, TypeProvider typeProvider, VariableResolver variableResolver, ResolvableType componentType) {
+			Type type, @Nullable TypeProvider typeProvider, @Nullable VariableResolver variableResolver, ResolvableType componentType) {
 
 		this.type = type;
 		this.typeProvider = typeProvider;
@@ -257,7 +257,7 @@ public class ResolvableType implements Serializable {
 		return isAssignableFrom(other, null);
 	}
 
-	private boolean isAssignableFrom(ResolvableType other, Map<Type, Type> matchedBefore) {
+	private boolean isAssignableFrom(ResolvableType other, @Nullable Map<Type, Type> matchedBefore) {
 		Assert.notNull(other, "ResolvableType must not be null");
 
 		// If we cannot resolve types, we are not assignable
@@ -700,7 +700,7 @@ public class ResolvableType implements Serializable {
 	 * @see #getGenerics()
 	 * @see #resolve()
 	 */
-	public Class<?>[] resolveGenerics(Class<?> fallback) {
+	public Class<?>[] resolveGenerics(@Nullable Class<?> fallback) {
 		ResolvableType[] generics = getGenerics();
 		Class<?>[] resolvedGenerics = new Class<?>[generics.length];
 		for (int i = 0; i < generics.length; i++) {

spring-core/src/main/java/org/springframework/core/annotation/AnnotatedElementUtils.java

@@ -241,8 +241,8 @@ public class AnnotatedElementUtils {
 		return hasMetaAnnotationTypes(element, null, annotationName);
 	}
 
-	private static boolean hasMetaAnnotationTypes(AnnotatedElement element, Class<? extends Annotation> annotationType,
-			String annotationName) {
+	private static boolean hasMetaAnnotationTypes(AnnotatedElement element, @Nullable Class<? extends Annotation> annotationType,
+			@Nullable String annotationName) {
 
 		return Boolean.TRUE.equals(
 			searchWithGetSemantics(element, annotationType, annotationName, new SimpleAnnotationProcessor<Boolean>() {
@@ -844,8 +844,8 @@ public class AnnotatedElementUtils {
 	 * @return the result of the processor, potentially {@code null}
 	 */
 	@Nullable
-	private static <T> T searchWithGetSemantics(AnnotatedElement element, Class<? extends Annotation> annotationType,
-			String annotationName, Processor<T> processor) {
+	private static <T> T searchWithGetSemantics(AnnotatedElement element, @Nullable Class<? extends Annotation> annotationType,
+			@Nullable String annotationName, Processor<T> processor) {
 
 		return searchWithGetSemantics(element, annotationType, annotationName, null, processor);
 	}
@@ -866,7 +866,7 @@ public class AnnotatedElementUtils {
 	 */
 	@Nullable
 	private static <T> T searchWithGetSemantics(AnnotatedElement element, Class<? extends Annotation> annotationType,
-			String annotationName, @Nullable Class<? extends Annotation> containerType, Processor<T> processor) {
+			@Nullable String annotationName, @Nullable Class<? extends Annotation> containerType, Processor<T> processor) {
 
 		try {
 			return searchWithGetSemantics(element, annotationType, annotationName, containerType, processor,
@@ -896,8 +896,8 @@ public class AnnotatedElementUtils {
 	 * @return the result of the processor, potentially {@code null}
 	 */
 	@Nullable
-	private static <T> T searchWithGetSemantics(AnnotatedElement element, Class<? extends Annotation> annotationType,
-			String annotationName, @Nullable Class<? extends Annotation> containerType, Processor<T> processor,
+	private static <T> T searchWithGetSemantics(AnnotatedElement element, @Nullable Class<? extends Annotation> annotationType,
+			@Nullable String annotationName, @Nullable Class<? extends Annotation> containerType, Processor<T> processor,
 			Set<AnnotatedElement> visited, int metaDepth) {
 
 		Assert.notNull(element, "AnnotatedElement must not be null");
@@ -1029,8 +1029,8 @@ public class AnnotatedElementUtils {
 	 * @since 4.2
 	 */
 	@Nullable
-	private static <T> T searchWithFindSemantics(AnnotatedElement element, Class<? extends Annotation> annotationType,
-			String annotationName, Processor<T> processor) {
+	private static <T> T searchWithFindSemantics(AnnotatedElement element, @Nullable Class<? extends Annotation> annotationType,
+			@Nullable String annotationName, Processor<T> processor) {
 
 		return searchWithFindSemantics(element, annotationType, annotationName, null, processor);
 	}
@@ -1051,7 +1051,7 @@ public class AnnotatedElementUtils {
 	 */
 	@Nullable
 	private static <T> T searchWithFindSemantics(AnnotatedElement element, Class<? extends Annotation> annotationType,
-			String annotationName, @Nullable Class<? extends Annotation> containerType, Processor<T> processor) {
+			@Nullable String annotationName, @Nullable Class<? extends Annotation> containerType, Processor<T> processor) {
 
 		if (containerType != null && !processor.aggregates()) {
 			throw new IllegalArgumentException(

spring-core/src/main/java/org/springframework/core/codec/ByteArrayDecoder.java

@@ -48,7 +48,7 @@ public class ByteArrayDecoder extends AbstractDecoder<byte[]> {
 	}
 
 	@Override
-	public Flux<byte[]> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+	public Flux<byte[]> decode(Publisher<DataBuffer> inputStream,@Nullable  ResolvableType elementType,
 			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
 
 		return Flux.from(inputStream).map((dataBuffer) -> {

spring-core/src/main/java/org/springframework/core/codec/ByteBufferDecoder.java

@@ -50,7 +50,7 @@ public class ByteBufferDecoder extends AbstractDecoder<ByteBuffer> {
 	}
 
 	@Override
-	public Flux<ByteBuffer> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+	public Flux<ByteBuffer> decode(Publisher<DataBuffer> inputStream, @Nullable ResolvableType elementType,
 			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
 
 		return Flux.from(inputStream).map((dataBuffer) -> {

spring-core/src/main/java/org/springframework/core/codec/DataBufferDecoder.java

@@ -50,7 +50,7 @@ public class DataBufferDecoder extends AbstractDecoder<DataBuffer> {
 	}
 
 	@Override
-	public Flux<DataBuffer> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+	public Flux<DataBuffer> decode(Publisher<DataBuffer> inputStream, @Nullable ResolvableType elementType,
 			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
 		return Flux.from(inputStream);
 	}

spring-core/src/main/java/org/springframework/core/codec/Decoder.java

@@ -58,7 +58,7 @@ public interface Decoder<T> {
 	 * @param hints additional information about how to do encode
 	 * @return the output stream with decoded elements
 	 */
-	Flux<T> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+	Flux<T> decode(Publisher<DataBuffer> inputStream, @Nullable ResolvableType elementType,
 			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints);
 
 	/**

spring-core/src/main/java/org/springframework/core/codec/ResourceDecoder.java

@@ -55,7 +55,7 @@ public class ResourceDecoder extends AbstractDecoder<Resource> {
 	}
 
 	@Override
-	public Flux<Resource> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+	public Flux<Resource> decode(Publisher<DataBuffer> inputStream, @Nullable ResolvableType elementType,
 			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
 
 		return Flux.from(decodeToMono(inputStream, elementType, mimeType, hints));

spring-core/src/main/java/org/springframework/core/codec/StringDecoder.java

@@ -77,7 +77,7 @@ public class StringDecoder extends AbstractDecoder<String> {
 	}
 
 	@Override
-	public Flux<String> decode(Publisher<DataBuffer> inputStream, ResolvableType elementType,
+	public Flux<String> decode(Publisher<DataBuffer> inputStream, @Nullable ResolvableType elementType,
 			@Nullable MimeType mimeType, @Nullable Map<String, Object> hints) {
 
 		Flux<DataBuffer> inputFlux = Flux.from(inputStream);

spring-core/src/main/java/org/springframework/core/convert/ConversionFailedException.java

@@ -16,6 +16,7 @@
 
 package org.springframework.core.convert;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.ObjectUtils;
 
 /**
@@ -42,7 +43,7 @@ public class ConversionFailedException extends ConversionException {
 	 * @param value the value we tried to convert
 	 * @param cause the cause of the conversion failure
 	 */
-	public ConversionFailedException(TypeDescriptor sourceType, TypeDescriptor targetType, Object value, Throwable cause) {
+	public ConversionFailedException(TypeDescriptor sourceType, TypeDescriptor targetType, @Nullable Object value, Throwable cause) {
 		super("Failed to convert from type [" + sourceType + "] to type [" + targetType +
 				"] for value '" + ObjectUtils.nullSafeToString(value) + "'", cause);
 		this.sourceType = sourceType;

spring-core/src/main/java/org/springframework/core/convert/Property.java

@@ -63,7 +63,7 @@ public final class Property {
 	private Annotation[] annotations;
 
 
-	public Property(Class<?> objectType, Method readMethod, Method writeMethod) {
+	public Property(Class<?> objectType, @Nullable Method readMethod, @Nullable Method writeMethod) {
 		this(objectType, readMethod, writeMethod, null);
 	}
 

spring-core/src/main/java/org/springframework/core/convert/TypeDescriptor.java

@@ -118,7 +118,7 @@ public class TypeDescriptor implements Serializable {
 	 * @param annotations the type annotations
 	 * @since 4.0
 	 */
-	protected TypeDescriptor(ResolvableType resolvableType, @Nullable Class<?> type, Annotation[] annotations) {
+	protected TypeDescriptor(ResolvableType resolvableType, @Nullable Class<?> type, @Nullable Annotation[] annotations) {
 		this.resolvableType = resolvableType;
 		this.type = (type != null ? type : resolvableType.resolve(Object.class));
 		this.annotatedElement = new AnnotatedElementAdapter(annotations);

spring-core/src/main/java/org/springframework/core/convert/support/GenericConversionService.java

@@ -230,7 +230,7 @@ public class GenericConversionService implements ConfigurableConversionService {
 	 * @return the converted null object
 	 */
 	@Nullable
-	protected Object convertNullSource(TypeDescriptor sourceType, TypeDescriptor targetType) {
+	protected Object convertNullSource(@Nullable TypeDescriptor sourceType, TypeDescriptor targetType) {
 		if (targetType.getObjectType() == Optional.class) {
 			return Optional.empty();
 		}
@@ -317,7 +317,7 @@ public class GenericConversionService implements ConfigurableConversionService {
 		throw new ConverterNotFoundException(sourceType, targetType);
 	}
 
-	private Object handleResult(TypeDescriptor sourceType, TypeDescriptor targetType, Object result) {
+	private Object handleResult(@Nullable TypeDescriptor sourceType, TypeDescriptor targetType, Object result) {
 		if (result == null) {
 			assertNotPrimitiveTargetType(sourceType, targetType);
 		}

spring-core/src/main/java/org/springframework/core/io/VfsUtils.java

@@ -25,6 +25,7 @@ import java.lang.reflect.Method;
 import java.net.URI;
 import java.net.URL;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -95,7 +96,7 @@ public abstract class VfsUtils {
 		}
 	}
 
-	protected static Object invokeVfsMethod(Method method, Object target, Object... args) throws IOException {
+	protected static Object invokeVfsMethod(Method method, @Nullable Object target, Object... args) throws IOException {
 		try {
 			return method.invoke(target, args);
 		}

spring-core/src/main/java/org/springframework/core/io/support/ResourcePropertySource.java

@@ -23,6 +23,7 @@ import java.util.Properties;
 import org.springframework.core.env.PropertiesPropertySource;
 import org.springframework.core.io.DefaultResourceLoader;
 import org.springframework.core.io.Resource;
+import org.springframework.lang.Nullable;
 import org.springframework.util.StringUtils;
 
 /**
@@ -124,7 +125,7 @@ public class ResourcePropertySource extends PropertiesPropertySource {
 		this(new DefaultResourceLoader().getResource(location));
 	}
 
-	private ResourcePropertySource(String name, String resourceName, Map<String, Object> source) {
+	private ResourcePropertySource(String name, @Nullable String resourceName, Map<String, Object> source) {
 		super(name, source);
 		this.resourceName = resourceName;
 	}

spring-core/src/main/java/org/springframework/util/AntPathMatcher.java

@@ -25,6 +25,8 @@ import java.util.concurrent.ConcurrentHashMap;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import org.springframework.lang.Nullable;
+
 /**
  * {@link PathMatcher} implementation for Ant-style path patterns.
  *
@@ -187,7 +189,7 @@ public class AntPathMatcher implements PathMatcher {
 	 * as far as the given base path goes is sufficient)
 	 * @return {@code true} if the supplied {@code path} matched, {@code false} if it didn't
 	 */
-	protected boolean doMatch(String pattern, String path, boolean fullMatch, Map<String, String> uriTemplateVariables) {
+	protected boolean doMatch(String pattern, String path, boolean fullMatch, @Nullable Map<String, String> uriTemplateVariables) {
 		if (path.startsWith(this.pathSeparator) != pattern.startsWith(this.pathSeparator)) {
 			return false;
 		}

spring-core/src/main/java/org/springframework/util/CollectionUtils.java

@@ -411,7 +411,7 @@ public abstract class CollectionUtils {
 		}
 
 		@Override
-		public void add(K key, V value) {
+		public void add(K key, @Nullable V value) {
 			List<V> values = this.map.computeIfAbsent(key, k -> new LinkedList<>());
 			values.add(value);
 		}

spring-core/src/main/java/org/springframework/util/LinkedMultiValueMap.java

@@ -24,6 +24,8 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
+import org.springframework.lang.Nullable;
+
 /**
  * Simple implementation of {@link MultiValueMap} that wraps a {@link LinkedHashMap},
  * storing multiple values in a {@link LinkedList}.
@@ -74,7 +76,7 @@ public class LinkedMultiValueMap<K, V> implements MultiValueMap<K, V>, Serializa
 	// MultiValueMap implementation
 
 	@Override
-	public void add(K key, V value) {
+	public void add(K key, @Nullable V value) {
 		List<V> values = this.targetMap.computeIfAbsent(key, k -> new LinkedList<>());
 		values.add(value);
 	}

spring-core/src/main/java/org/springframework/util/MultiValueMap.java

@@ -42,7 +42,7 @@ public interface MultiValueMap<K, V> extends Map<K, List<V>> {
 	 * @param key the key
 	 * @param value the value to be added
 	 */
-	void add(K key, V value);
+	void add(K key, @Nullable V value);
 
 	/**
 	 * Add all the values of the given list to the current list of values for the given key.

spring-core/src/main/java/org/springframework/util/ReflectionUtils.java

@@ -238,7 +238,7 @@ public abstract class ReflectionUtils {
 	 * @see #invokeJdbcMethod(java.lang.reflect.Method, Object, Object[])
 	 */
 	@Nullable
-	public static Object invokeJdbcMethod(Method method, Object target) throws SQLException {
+	public static Object invokeJdbcMethod(Method method, @Nullable Object target) throws SQLException {
 		return invokeJdbcMethod(method, target, new Object[0]);
 	}
 
@@ -547,7 +547,7 @@ public abstract class ReflectionUtils {
 	 * @param mf the filter that determines the methods to apply the callback to
 	 * @throws IllegalStateException if introspection fails
 	 */
-	public static void doWithMethods(Class<?> clazz, MethodCallback mc, MethodFilter mf) {
+	public static void doWithMethods(Class<?> clazz, MethodCallback mc, @Nullable MethodFilter mf) {
 		// Keep backing up the inheritance hierarchy.
 		Method[] methods = getDeclaredMethods(clazz);
 		for (Method method : methods) {
@@ -720,7 +720,7 @@ public abstract class ReflectionUtils {
 	 * @param ff the filter that determines the fields to apply the callback to
 	 * @throws IllegalStateException if introspection fails
 	 */
-	public static void doWithFields(Class<?> clazz, FieldCallback fc, FieldFilter ff) {
+	public static void doWithFields(Class<?> clazz, FieldCallback fc, @Nullable FieldFilter ff) {
 		// Keep backing up the inheritance hierarchy.
 		Class<?> targetClass = clazz;
 		do {

spring-core/src/main/java/org/springframework/util/StringUtils.java

@@ -1065,7 +1065,7 @@ public abstract class StringUtils {
 	 */
 	@Nullable
 	public static Properties splitArrayElementsIntoProperties(
-			String[] array, String delimiter, String charsToDelete) {
+			String[] array, String delimiter, @Nullable String charsToDelete) {
 
 		if (ObjectUtils.isEmpty(array)) {
 			return null;
@@ -1179,7 +1179,7 @@ public abstract class StringUtils {
 	 * @return an array of the tokens in the list
 	 * @see #tokenizeToStringArray
 	 */
-	public static String[] delimitedListToStringArray(String str, String delimiter, String charsToDelete) {
+	public static String[] delimitedListToStringArray(String str, String delimiter, @Nullable String charsToDelete) {
 		if (str == null) {
 			return new String[0];
 		}

spring-core/src/main/java/org/springframework/util/concurrent/ListenableFutureTask.java

@@ -20,6 +20,8 @@ import java.util.concurrent.Callable;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.FutureTask;
 
+import org.springframework.lang.Nullable;
+
 /**
  * Extension of {@link FutureTask} that implements {@link ListenableFuture}.
  *
@@ -47,7 +49,7 @@ public class ListenableFutureTask<T> extends FutureTask<T> implements Listenable
 	 * @param runnable the runnable task
 	 * @param result the result to return on successful completion
 	 */
-	public ListenableFutureTask(Runnable runnable, T result) {
+	public ListenableFutureTask(Runnable runnable, @Nullable T result) {
 		super(runnable, result);
 	}
 

spring-core/src/main/java/org/springframework/util/concurrent/SettableListenableFuture.java

@@ -21,6 +21,7 @@ import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -54,7 +55,7 @@ public class SettableListenableFuture<T> implements ListenableFuture<T> {
 	 * @param value the value that will be set
 	 * @return {@code true} if the value was successfully set, else {@code false}
 	 */
-	public boolean set(T value) {
+	public boolean set(@Nullable T value) {
 		return this.settableTask.setResultValue(value);
 	}
 

spring-expression/src/main/java/org/springframework/expression/TypedValue.java

@@ -17,6 +17,7 @@
 package org.springframework.expression;
 
 import org.springframework.core.convert.TypeDescriptor;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ObjectUtils;
 
 /**
@@ -43,7 +44,7 @@ public class TypedValue {
 	 * is inferred from the object, so no generic declarations are preserved.
 	 * @param value the object value
 	 */
-	public TypedValue(Object value) {
+	public TypedValue(@Nullable Object value) {
 		this.value = value;
 		this.typeDescriptor = null;  // initialized when/if requested
 	}
@@ -54,12 +55,13 @@ public class TypedValue {
 	 * @param value the object value
 	 * @param typeDescriptor a type descriptor describing the type of the value
 	 */
-	public TypedValue(Object value, TypeDescriptor typeDescriptor) {
+	public TypedValue(@Nullable Object value, @Nullable TypeDescriptor typeDescriptor) {
 		this.value = value;
 		this.typeDescriptor = typeDescriptor;
 	}
 
 
+	@Nullable
 	public Object getValue() {
 		return this.value;
 	}

spring-expression/src/main/java/org/springframework/expression/common/ExpressionUtils.java

@@ -21,6 +21,7 @@ import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.EvaluationException;
 import org.springframework.expression.TypeConverter;
 import org.springframework.expression.TypedValue;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 
 /**
@@ -44,7 +45,7 @@ public abstract class ExpressionUtils {
 	 * of the value to the specified type is not supported
 	 */
 	@SuppressWarnings("unchecked")
-	public static <T> T convertTypedValue(EvaluationContext context, TypedValue typedValue, Class<T> targetType) {
+	public static <T> T convertTypedValue(@Nullable EvaluationContext context, TypedValue typedValue, Class<T> targetType) {
 		Object value = typedValue.getValue();
 		if (targetType == null) {
 			return (T) value;

spring-expression/src/main/java/org/springframework/expression/common/TemplateAwareExpressionParser.java

@@ -24,6 +24,7 @@ import org.springframework.expression.Expression;
 import org.springframework.expression.ExpressionParser;
 import org.springframework.expression.ParseException;
 import org.springframework.expression.ParserContext;
+import org.springframework.lang.Nullable;
 
 /**
  * An expression parser that understands templates. It can be subclassed by expression
@@ -255,7 +256,7 @@ public abstract class TemplateAwareExpressionParser implements ExpressionParser
 	 * @return an evaluator for the parsed expression
 	 * @throws ParseException an exception occurred during parsing
 	 */
-	protected abstract Expression doParseExpression(String expressionString, ParserContext context)
+	protected abstract Expression doParseExpression(String expressionString, @Nullable ParserContext context)
 			throws ParseException;
 
 

spring-expression/src/main/java/org/springframework/expression/spel/CompiledExpression.java

@@ -18,6 +18,7 @@ package org.springframework.expression.spel;
 
 import org.springframework.expression.EvaluationContext;
 import org.springframework.expression.EvaluationException;
+import org.springframework.lang.Nullable;
 
 /**
  * Base superclass for compiled expressions. Each generated compiled expression class
@@ -33,6 +34,6 @@ public abstract class CompiledExpression {
 	 * Subclasses of CompiledExpression generated by SpelCompiler will provide an
 	 * implementation of this method.
 	 */
-	public abstract Object getValue(Object target, EvaluationContext context) throws EvaluationException;
+	public abstract Object getValue(Object target, @Nullable EvaluationContext context) throws EvaluationException;
 
 }

spring-expression/src/main/java/org/springframework/expression/spel/ExpressionState.java

@@ -217,7 +217,7 @@ public class ExpressionState {
 		return null;
 	}
 
-	public TypedValue operate(Operation op, Object left, Object right) throws EvaluationException {
+	public TypedValue operate(Operation op, Object left, @Nullable Object right) throws EvaluationException {
 		OperatorOverloader overloader = this.relatedContext.getOperatorOverloader();
 		if (overloader.overridesOperation(op, left, right)) {
 			Object returnValue = overloader.operate(op, left, right);

spring-expression/src/main/java/org/springframework/expression/spel/SpelParserConfiguration.java

@@ -17,6 +17,7 @@
 package org.springframework.expression.spel;
 
 import org.springframework.core.SpringProperties;
+import org.springframework.lang.Nullable;
 
 
 /**
@@ -62,7 +63,7 @@ public class SpelParserConfiguration {
 	 * @param compilerMode the compiler mode for the parser
 	 * @param compilerClassLoader the ClassLoader to use as the basis for expression compilation
 	 */
-	public SpelParserConfiguration(SpelCompilerMode compilerMode, ClassLoader compilerClassLoader) {
+	public SpelParserConfiguration(@Nullable SpelCompilerMode compilerMode, ClassLoader compilerClassLoader) {
 		this(compilerMode, compilerClassLoader, false, false, Integer.MAX_VALUE);
 	}
 

spring-expression/src/main/java/org/springframework/expression/spel/ast/FormatHelper.java

@@ -19,6 +19,7 @@ package org.springframework.expression.spel.ast;
 import java.util.List;
 
 import org.springframework.core.convert.TypeDescriptor;
+import org.springframework.lang.Nullable;
 import org.springframework.util.ClassUtils;
 
 /**
@@ -60,7 +61,7 @@ public class FormatHelper {
 	 * @return a formatted String suitable for message inclusion
 	 * @see ClassUtils#getQualifiedName(Class)
 	 */
-	public static String formatClassNameForMessage(Class<?> clazz) {
+	public static String formatClassNameForMessage(@Nullable Class<?> clazz) {
 		return (clazz != null ? ClassUtils.getQualifiedName(clazz) : "null");
 	}
 

spring-expression/src/main/java/org/springframework/expression/spel/standard/InternalSpelExpressionParser.java

@@ -117,7 +117,7 @@ class InternalSpelExpressionParser extends TemplateAwareExpressionParser {
 
 
 	@Override
-	protected SpelExpression doParseExpression(String expressionString, ParserContext context) throws ParseException {
+	protected SpelExpression doParseExpression(String expressionString, @Nullable ParserContext context) throws ParseException {
 		try {
 			this.expressionString = expressionString;
 			Tokenizer tokenizer = new Tokenizer(expressionString);

spring-expression/src/main/java/org/springframework/expression/spel/standard/SpelExpressionParser.java

@@ -20,6 +20,7 @@ import org.springframework.expression.ParseException;
 import org.springframework.expression.ParserContext;
 import org.springframework.expression.common.TemplateAwareExpressionParser;
 import org.springframework.expression.spel.SpelParserConfiguration;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -56,7 +57,7 @@ public class SpelExpressionParser extends TemplateAwareExpressionParser {
 	}
 
 	@Override
-	protected SpelExpression doParseExpression(String expressionString, ParserContext context) throws ParseException {
+	protected SpelExpression doParseExpression(String expressionString, @Nullable ParserContext context) throws ParseException {
 		return new InternalSpelExpressionParser(this.configuration).doParseExpression(expressionString, context);
 	}
 

spring-expression/src/main/java/org/springframework/expression/spel/support/StandardEvaluationContext.java

@@ -34,6 +34,7 @@ import org.springframework.expression.TypeComparator;
 import org.springframework.expression.TypeConverter;
 import org.springframework.expression.TypeLocator;
 import org.springframework.expression.TypedValue;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -84,7 +85,7 @@ public class StandardEvaluationContext implements EvaluationContext {
 		this.rootObject = new TypedValue(rootObject, typeDescriptor);
 	}
 
-	public void setRootObject(Object rootObject) {
+	public void setRootObject(@Nullable Object rootObject) {
 		this.rootObject = (rootObject != null ? new TypedValue(rootObject) : TypedValue.NULL);
 	}
 

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

@@ -31,6 +31,7 @@ import org.springframework.core.io.ResourceLoader;
 import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
 import org.springframework.core.io.support.ResourcePatternResolver;
 import org.springframework.core.io.support.ResourcePatternUtils;
+import org.springframework.lang.Nullable;
 
 /**
  * {@link FactoryBean} implementation that takes a list of location Strings
@@ -60,7 +61,7 @@ public class SortedResourcesFactoryBean extends AbstractFactoryBean<Resource[]>
 
 
 	@Override
-	public void setResourceLoader(ResourceLoader resourceLoader) {
+	public void setResourceLoader(@Nullable ResourceLoader resourceLoader) {
 		this.resourcePatternResolver = ResourcePatternUtils.getResourcePatternResolver(resourceLoader);
 	}
 

spring-jdbc/src/main/java/org/springframework/jdbc/core/JdbcTemplate.java

@@ -627,7 +627,7 @@ public class JdbcTemplate extends JdbcAccessor implements JdbcOperations {
 	 * @throws DataAccessException if there is any problem
 	 */
 	public <T> T query(
-			PreparedStatementCreator psc, final PreparedStatementSetter pss, final ResultSetExtractor<T> rse)
+			PreparedStatementCreator psc, @Nullable final PreparedStatementSetter pss, final ResultSetExtractor<T> rse)
 			throws DataAccessException {
 
 		Assert.notNull(rse, "ResultSetExtractor must not be null");

spring-jdbc/src/main/java/org/springframework/jdbc/core/StatementCreatorUtils.java

@@ -193,7 +193,7 @@ public abstract class StatementCreatorUtils {
 	 * @see SqlTypeValue
 	 */
 	private static void setParameterValueInternal(PreparedStatement ps, int paramIndex, int sqlType,
-			String typeName, Integer scale, Object inValue) throws SQLException {
+			@Nullable String typeName, @Nullable Integer scale, Object inValue) throws SQLException {
 
 		String typeNameToUse = typeName;
 		int sqlTypeToUse = sqlType;

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/NamedParameterJdbcTemplate.java

@@ -37,6 +37,7 @@ import org.springframework.jdbc.core.SqlParameter;
 import org.springframework.jdbc.core.SqlRowSetResultSetExtractor;
 import org.springframework.jdbc.support.KeyHolder;
 import org.springframework.jdbc.support.rowset.SqlRowSet;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
 /**
@@ -301,7 +302,7 @@ public class NamedParameterJdbcTemplate implements NamedParameterJdbcOperations
 
 	@Override
 	public int update(
-			String sql, SqlParameterSource paramSource, KeyHolder generatedKeyHolder, String[] keyColumnNames)
+			String sql, SqlParameterSource paramSource, KeyHolder generatedKeyHolder, @Nullable String[] keyColumnNames)
 			throws DataAccessException {
 
 		ParsedSql parsedSql = getParsedSql(sql);

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/NamedParameterUtils.java

@@ -256,7 +256,7 @@ public abstract class NamedParameterUtils {
 	 * @return the SQL statement with substituted parameters
 	 * @see #parseSqlStatement
 	 */
-	public static String substituteNamedParameters(ParsedSql parsedSql, SqlParameterSource paramSource) {
+	public static String substituteNamedParameters(ParsedSql parsedSql, @Nullable SqlParameterSource paramSource) {
 		String originalSql = parsedSql.getOriginalSql();
 		StringBuilder actualSql = new StringBuilder();
 		List<String> paramNames = parsedSql.getParameterNames();

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/DataSourceTransactionManager.java

@@ -22,6 +22,7 @@ import java.sql.Statement;
 import javax.sql.DataSource;
 
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.lang.Nullable;
 import org.springframework.transaction.CannotCreateTransactionException;
 import org.springframework.transaction.TransactionDefinition;
 import org.springframework.transaction.TransactionSystemException;
@@ -413,7 +414,7 @@ public class DataSourceTransactionManager extends AbstractPlatformTransactionMan
 
 		private boolean mustRestoreAutoCommit;
 
-		public void setConnectionHolder(ConnectionHolder connectionHolder, boolean newConnectionHolder) {
+		public void setConnectionHolder(@Nullable ConnectionHolder connectionHolder, boolean newConnectionHolder) {
 			super.setConnectionHolder(connectionHolder);
 			this.newConnectionHolder = newConnectionHolder;
 		}

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/JdbcTransactionObjectSupport.java

@@ -22,6 +22,7 @@ import java.sql.Savepoint;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
+import org.springframework.lang.Nullable;
 import org.springframework.transaction.CannotCreateTransactionException;
 import org.springframework.transaction.NestedTransactionNotSupportedException;
 import org.springframework.transaction.SavepointManager;
@@ -56,7 +57,7 @@ public abstract class JdbcTransactionObjectSupport implements SavepointManager,
 	private boolean savepointAllowed = false;
 
 
-	public void setConnectionHolder(ConnectionHolder connectionHolder) {
+	public void setConnectionHolder(@Nullable ConnectionHolder connectionHolder) {
 		this.connectionHolder = connectionHolder;
 	}
 

spring-jdbc/src/main/java/org/springframework/jdbc/datasource/init/ScriptUtils.java

@@ -30,6 +30,7 @@ import org.apache.commons.logging.LogFactory;
 
 import org.springframework.core.io.Resource;
 import org.springframework.core.io.support.EncodedResource;
+import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
@@ -164,7 +165,7 @@ public abstract class ScriptUtils {
 	 * @param statements the list that will contain the individual statements
 	 * @throws ScriptException if an error occurred while splitting the SQL script
 	 */
-	public static void splitSqlScript(EncodedResource resource, String script, String separator, String commentPrefix,
+	public static void splitSqlScript(@Nullable EncodedResource resource, String script, String separator, String commentPrefix,
 			String blockCommentStartDelimiter, String blockCommentEndDelimiter, List<String> statements)
 			throws ScriptException {
 

spring-jdbc/src/main/java/org/springframework/jdbc/object/SqlQuery.java

@@ -107,7 +107,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @return a List of objects, one per row of the ResultSet. Normally all these
 	 * will be of the same class, although it is possible to use different types.
 	 */
-	public List<T> execute(Object[] params, Map<?, ?> context) throws DataAccessException {
+	public List<T> execute(Object[] params, @Nullable Map<?, ?> context) throws DataAccessException {
 		validateParameters(params);
 		RowMapper<T> rowMapper = newRowMapper(params, context);
 		return getJdbcTemplate().query(newPreparedStatementCreator(params), rowMapper);
@@ -143,7 +143,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @param p1 single int parameter
 	 * @param context the contextual information for object creation
 	 */
-	public List<T> execute(int p1, Map<?, ?> context) throws DataAccessException {
+	public List<T> execute(int p1, @Nullable Map<?, ?> context) throws DataAccessException {
 		return execute(new Object[] {p1}, context);
 	}
 
@@ -161,7 +161,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @param p2 second int parameter
 	 * @param context the contextual information for object creation
 	 */
-	public List<T> execute(int p1, int p2, Map<?, ?> context) throws DataAccessException {
+	public List<T> execute(int p1, int p2, @Nullable Map<?, ?> context) throws DataAccessException {
 		return execute(new Object[] {p1, p2}, context);
 	}
 
@@ -179,7 +179,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @param p1 single long parameter
 	 * @param context the contextual information for object creation
 	 */
-	public List<T> execute(long p1, Map<?, ?> context) throws DataAccessException {
+	public List<T> execute(long p1, @Nullable Map<?, ?> context) throws DataAccessException {
 		return execute(new Object[] {p1}, context);
 	}
 
@@ -196,7 +196,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @param p1 single String parameter
 	 * @param context the contextual information for object creation
 	 */
-	public List<T> execute(String p1, Map<?, ?> context) throws DataAccessException {
+	public List<T> execute(String p1, @Nullable Map<?, ?> context) throws DataAccessException {
 		return execute(new Object[] {p1}, context);
 	}
 
@@ -220,7 +220,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @return a List of objects, one per row of the ResultSet. Normally all these
 	 * will be of the same class, although it is possible to use different types.
 	 */
-	public List<T> executeByNamedParam(Map<String, ?> paramMap, Map<?, ?> context) throws DataAccessException {
+	public List<T> executeByNamedParam(Map<String, ?> paramMap, @Nullable Map<?, ?> context) throws DataAccessException {
 		validateNamedParameters(paramMap);
 		ParsedSql parsedSql = getParsedSql();
 		MapSqlParameterSource paramSource = new MapSqlParameterSource(paramMap);
@@ -250,7 +250,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @see org.springframework.dao.support.DataAccessUtils#singleResult
 	 */
 	@Nullable
-	public T findObject(Object[] params, Map<?, ?> context) throws DataAccessException {
+	public T findObject(Object[] params, @Nullable Map<?, ?> context) throws DataAccessException {
 		List<T> results = execute(params, context);
 		return DataAccessUtils.singleResult(results);
 	}
@@ -266,7 +266,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * Convenient method to find a single object given a single int parameter
 	 * and a context.
 	 */
-	public T findObject(int p1, Map<?, ?> context) throws DataAccessException {
+	public T findObject(int p1, @Nullable Map<?, ?> context) throws DataAccessException {
 		return findObject(new Object[] {p1}, context);
 	}
 
@@ -281,7 +281,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * Convenient method to find a single object given two int parameters
 	 * and a context.
 	 */
-	public T findObject(int p1, int p2, Map<?, ?> context) throws DataAccessException {
+	public T findObject(int p1, int p2, @Nullable Map<?, ?> context) throws DataAccessException {
 		return findObject(new Object[] {p1, p2}, context);
 	}
 
@@ -296,7 +296,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * Convenient method to find a single object given a single long parameter
 	 * and a context.
 	 */
-	public T findObject(long p1, Map<?, ?> context) throws DataAccessException {
+	public T findObject(long p1, @Nullable Map<?, ?> context) throws DataAccessException {
 		return findObject(new Object[] {p1}, context);
 	}
 
@@ -311,7 +311,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * Convenient method to find a single object given a single String parameter
 	 * and a context.
 	 */
-	public T findObject(String p1, Map<?, ?> context) throws DataAccessException {
+	public T findObject(String p1, @Nullable Map<?, ?> context) throws DataAccessException {
 		return findObject(new Object[] {p1}, context);
 	}
 
@@ -333,7 +333,7 @@ public abstract class SqlQuery<T> extends SqlOperation {
 	 * @return a List of objects, one per row of the ResultSet. Normally all these
 	 * will be of the same class, although it is possible to use different types.
 	 */
-	public T findObjectByNamedParam(Map<String, ?> paramMap, Map<?, ?> context) throws DataAccessException {
+	public T findObjectByNamedParam(Map<String, ?> paramMap, @Nullable Map<?, ?> context) throws DataAccessException {
 		List<T> results = executeByNamedParam(paramMap, context);
 		return DataAccessUtils.singleResult(results);
 	}

spring-jms/src/main/java/org/springframework/jms/connection/CachingConnectionFactory.java

@@ -400,7 +400,7 @@ public class CachingConnectionFactory extends SingleConnectionFactory {
 		}
 
 		private MessageConsumer getCachedConsumer(
-				Destination dest, String selector, Boolean noLocal, String subscription, boolean durable) throws JMSException {
+				Destination dest, String selector, @Nullable Boolean noLocal, @Nullable String subscription, boolean durable) throws JMSException {
 
 			ConsumerCacheKey cacheKey = new ConsumerCacheKey(dest, selector, noLocal, subscription, durable);
 			MessageConsumer consumer = this.cachedConsumers.get(cacheKey);

spring-jms/src/main/java/org/springframework/jms/connection/JmsResourceHolder.java

@@ -134,7 +134,7 @@ public class JmsResourceHolder extends ResourceHolderSupport {
 		addSession(session, null);
 	}
 
-	public final void addSession(Session session, Connection connection) {
+	public final void addSession(Session session, @Nullable Connection connection) {
 		Assert.isTrue(!this.frozen, "Cannot add Session because JmsResourceHolder is frozen");
 		Assert.notNull(session, "Session must not be null");
 		if (!this.sessions.contains(session)) {
@@ -171,7 +171,7 @@ public class JmsResourceHolder extends ResourceHolderSupport {
 		return getSession(sessionType, null);
 	}
 
-	public Session getSession(Class<? extends Session> sessionType, Connection connection) {
+	public Session getSession(Class<? extends Session> sessionType, @Nullable Connection connection) {
 		List<Session> sessions = this.sessions;
 		if (connection != null) {
 			sessions = this.sessionsPerConnection.get(connection);

spring-jms/src/main/java/org/springframework/jms/connection/JmsTransactionManager.java

@@ -23,6 +23,7 @@ import javax.jms.Session;
 import javax.jms.TransactionRolledBackException;
 
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.lang.Nullable;
 import org.springframework.transaction.CannotCreateTransactionException;
 import org.springframework.transaction.InvalidIsolationLevelException;
 import org.springframework.transaction.TransactionDefinition;
@@ -308,7 +309,7 @@ public class JmsTransactionManager extends AbstractPlatformTransactionManager
 
 		private JmsResourceHolder resourceHolder;
 
-		public void setResourceHolder(JmsResourceHolder resourceHolder) {
+		public void setResourceHolder(@Nullable JmsResourceHolder resourceHolder) {
 			this.resourceHolder = resourceHolder;
 		}