Support for MultiValueMap elements in bean property paths

Closes gh-26297

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

@@ -319,14 +319,14 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 		}
 
 		else if (propValue instanceof List list) {
-			Class<?> requiredType = ph.getCollectionType(tokens.keys.length);
+			TypeDescriptor requiredType = ph.getCollectionType(tokens.keys.length);
 			int index = Integer.parseInt(lastKey);
 			Object oldValue = null;
 			if (isExtractOldValueForEditor() && index < list.size()) {
 				oldValue = list.get(index);
 			}
 			Object convertedValue = convertIfNecessary(tokens.canonicalName, oldValue, pv.getValue(),
-					requiredType, ph.nested(tokens.keys.length));
+					requiredType.getResolvableType().resolve(), requiredType);
 			int size = list.size();
 			if (index >= size && index < this.autoGrowCollectionLimit) {
 				for (int i = size; i < index; i++) {
@@ -354,12 +354,12 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 		}
 
 		else if (propValue instanceof Map map) {
-			Class<?> mapKeyType = ph.getMapKeyType(tokens.keys.length);
+			TypeDescriptor mapKeyType = ph.getMapKeyType(tokens.keys.length);
-			Class<?> mapValueType = ph.getMapValueType(tokens.keys.length);
+			TypeDescriptor mapValueType = ph.getMapValueType(tokens.keys.length);
 			// IMPORTANT: Do not pass full property name in here - property editors
 			// must not kick in for map keys but rather only for map values.
-			TypeDescriptor typeDescriptor = TypeDescriptor.valueOf(mapKeyType);
+			Object convertedMapKey = convertIfNecessary(null, null, lastKey,
-			Object convertedMapKey = convertIfNecessary(null, null, lastKey, mapKeyType, typeDescriptor);
+					mapKeyType.getResolvableType().resolve(), mapKeyType);
 			Object oldValue = null;
 			if (isExtractOldValueForEditor()) {
 				oldValue = map.get(convertedMapKey);
@@ -367,7 +367,7 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 			// Pass full property name and old value in here, since we want full
 			// conversion ability for map values.
 			Object convertedMapValue = convertIfNecessary(tokens.canonicalName, oldValue, pv.getValue(),
-					mapValueType, ph.nested(tokens.keys.length));
+					mapValueType.getResolvableType().resolve(), mapValueType);
 			map.put(convertedMapKey, convertedMapValue);
 		}
 
@@ -1041,19 +1041,16 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 
 		public abstract ResolvableType getResolvableType();
 
-		@Nullable
+		public TypeDescriptor getMapKeyType(int nestingLevel) {
-		public Class<?> getMapKeyType(int nestingLevel) {
+			return TypeDescriptor.valueOf(getResolvableType().getNested(nestingLevel).asMap().resolveGeneric(0));
-			return getResolvableType().getNested(nestingLevel).asMap().resolveGeneric(0);
 		}
 
-		@Nullable
+		public TypeDescriptor getMapValueType(int nestingLevel) {
-		public Class<?> getMapValueType(int nestingLevel) {
+			return TypeDescriptor.valueOf(getResolvableType().getNested(nestingLevel).asMap().resolveGeneric(1));
-			return getResolvableType().getNested(nestingLevel).asMap().resolveGeneric(1);
 		}
 
-		@Nullable
+		public TypeDescriptor getCollectionType(int nestingLevel) {
-		public Class<?> getCollectionType(int nestingLevel) {
+			return TypeDescriptor.valueOf(getResolvableType().getNested(nestingLevel).asCollection().resolveGeneric());
-			return getResolvableType().getNested(nestingLevel).asCollection().resolveGeneric();
 		}
 
 		@Nullable

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -236,19 +236,36 @@ public class BeanWrapperImpl extends AbstractNestablePropertyAccessor implements
 
 		private final PropertyDescriptor pd;
 
+		private final TypeDescriptor typeDescriptor;
+
 		public BeanPropertyHandler(PropertyDescriptor pd) {
 			super(pd.getPropertyType(), pd.getReadMethod() != null, pd.getWriteMethod() != null);
 			this.pd = pd;
-		}
+			this.typeDescriptor = new TypeDescriptor(property(pd));
-
-		@Override
-		public ResolvableType getResolvableType() {
-			return ResolvableType.forMethodReturnType(this.pd.getReadMethod());
 		}
 
 		@Override
 		public TypeDescriptor toTypeDescriptor() {
-			return new TypeDescriptor(property(this.pd));
+			return this.typeDescriptor;
+		}
+
+		@Override
+		public ResolvableType getResolvableType() {
+			return this.typeDescriptor.getResolvableType();
+		}
+
+		@Override
+		public TypeDescriptor getMapValueType(int nestingLevel) {
+			return new TypeDescriptor(
+					this.typeDescriptor.getResolvableType().getNested(nestingLevel).asMap().getGeneric(1),
+					null, this.typeDescriptor.getAnnotations());
+		}
+
+		@Override
+		public TypeDescriptor getCollectionType(int nestingLevel) {
+			return new TypeDescriptor(
+					this.typeDescriptor.getResolvableType().getNested(nestingLevel).asCollection().getGeneric(),
+					null, this.typeDescriptor.getAnnotations());
 		}
 
 		@Override

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2023 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -101,19 +101,34 @@ public class DirectFieldAccessor extends AbstractNestablePropertyAccessor {
 
 		private final Field field;
 
+		private final ResolvableType resolvableType;
+
 		public FieldPropertyHandler(Field field) {
 			super(field.getType(), true, true);
 			this.field = field;
+			this.resolvableType = ResolvableType.forField(this.field);
 		}
 
 		@Override
 		public TypeDescriptor toTypeDescriptor() {
-			return new TypeDescriptor(this.field);
+			return new TypeDescriptor(this.resolvableType, this.field.getType(), this.field.getAnnotations());
 		}
 
 		@Override
 		public ResolvableType getResolvableType() {
-			return ResolvableType.forField(this.field);
+			return this.resolvableType;
+		}
+
+		@Override
+		public TypeDescriptor getMapValueType(int nestingLevel) {
+			return new TypeDescriptor(this.resolvableType.getNested(nestingLevel).asMap().getGeneric(1),
+					null, this.field.getAnnotations());
+		}
+
+		@Override
+		public TypeDescriptor getCollectionType(int nestingLevel) {
+			return new TypeDescriptor(this.resolvableType.getNested(nestingLevel).asCollection().getGeneric(),
+					null, this.field.getAnnotations());
 		}
 
 		@Override

spring-beans/src/test/java/org/springframework/beans/BeanWrapperGenericsTests.java

@@ -36,6 +36,8 @@ import org.springframework.beans.testfixture.beans.GenericIntegerBean;
 import org.springframework.beans.testfixture.beans.GenericSetOfIntegerBean;
 import org.springframework.beans.testfixture.beans.TestBean;
 import org.springframework.core.io.UrlResource;
+import org.springframework.util.LinkedMultiValueMap;
+import org.springframework.util.MultiValueMap;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
@@ -429,6 +431,18 @@ class BeanWrapperGenericsTests {
 		assertThat(holder.getGenericIndexedMap().values().iterator().next().get(0)).isEqualTo(Long.valueOf(10));
 	}
 
+	@Test
+	void testComplexGenericIndexedMapEntryWithPlainValue() {
+		String inputValue = "10";
+
+		ComplexMapHolder holder = new ComplexMapHolder();
+		BeanWrapper bw = new BeanWrapperImpl(holder);
+		bw.setPropertyValue("genericIndexedMap[1]", inputValue);
+
+		assertThat(holder.getGenericIndexedMap().keySet().iterator().next()).isEqualTo(1);
+		assertThat(holder.getGenericIndexedMap().values().iterator().next().get(0)).isEqualTo(Long.valueOf(10));
+	}
+
 	@Test
 	void testComplexDerivedIndexedMapEntry() {
 		List<String> inputValue = new ArrayList<>();
@@ -455,6 +469,56 @@ class BeanWrapperGenericsTests {
 		assertThat(holder.getDerivedIndexedMap().values().iterator().next().get(0)).isEqualTo(Long.valueOf(10));
 	}
 
+	@Test
+	void testComplexDerivedIndexedMapEntryWithPlainValue() {
+		String inputValue = "10";
+
+		ComplexMapHolder holder = new ComplexMapHolder();
+		BeanWrapper bw = new BeanWrapperImpl(holder);
+		bw.setPropertyValue("derivedIndexedMap[1]", inputValue);
+
+		assertThat(holder.getDerivedIndexedMap().keySet().iterator().next()).isEqualTo(1);
+		assertThat(holder.getDerivedIndexedMap().values().iterator().next().get(0)).isEqualTo(Long.valueOf(10));
+	}
+
+	@Test
+	void testComplexMultiValueMapEntry() {
+		List<String> inputValue = new ArrayList<>();
+		inputValue.add("10");
+
+		ComplexMapHolder holder = new ComplexMapHolder();
+		BeanWrapper bw = new BeanWrapperImpl(holder);
+		bw.setPropertyValue("multiValueMap[1]", inputValue);
+
+		assertThat(holder.getMultiValueMap().keySet().iterator().next()).isEqualTo(1);
+		assertThat(holder.getMultiValueMap().values().iterator().next().get(0)).isEqualTo(Long.valueOf(10));
+	}
+
+	@Test
+	void testComplexMultiValueMapEntryWithCollectionConversion() {
+		Set<String> inputValue = new HashSet<>();
+		inputValue.add("10");
+
+		ComplexMapHolder holder = new ComplexMapHolder();
+		BeanWrapper bw = new BeanWrapperImpl(holder);
+		bw.setPropertyValue("multiValueMap[1]", inputValue);
+
+		assertThat(holder.getMultiValueMap().keySet().iterator().next()).isEqualTo(1);
+		assertThat(holder.getMultiValueMap().values().iterator().next().get(0)).isEqualTo(Long.valueOf(10));
+	}
+
+	@Test
+	void testComplexMultiValueMapEntryWithPlainValue() {
+		String inputValue = "10";
+
+		ComplexMapHolder holder = new ComplexMapHolder();
+		BeanWrapper bw = new BeanWrapperImpl(holder);
+		bw.setPropertyValue("multiValueMap[1]", inputValue);
+
+		assertThat(holder.getMultiValueMap().keySet().iterator().next()).isEqualTo(1);
+		assertThat(holder.getMultiValueMap().values().iterator().next().get(0)).isEqualTo(Long.valueOf(10));
+	}
+
 	@Test
 	void testGenericallyTypedIntegerBean() {
 		GenericIntegerBean gb = new GenericIntegerBean();
@@ -585,6 +649,8 @@ class BeanWrapperGenericsTests {
 
 		private DerivedMap derivedIndexedMap = new DerivedMap();
 
+		private MultiValueMap<Integer, Long> multiValueMap = new LinkedMultiValueMap<>();
+
 		public void setGenericMap(Map<List<Integer>, List<Long>> genericMap) {
 			this.genericMap = genericMap;
 		}
@@ -608,6 +674,14 @@ class BeanWrapperGenericsTests {
 		public DerivedMap getDerivedIndexedMap() {
 			return derivedIndexedMap;
 		}
+
+		public void setMultiValueMap(MultiValueMap<Integer, Long> multiValueMap) {
+			this.multiValueMap = multiValueMap;
+		}
+
+		public MultiValueMap<Integer, Long> getMultiValueMap() {
+			return multiValueMap;
+		}
 	}