Move to Spring Data Commons' association abstraction.

Deprecated Spring Data JDBC's custom PersistentProperty.isReference() in favor of the already existing ….isAssociation() with the same semantics to benefit from association definitions implemented in Spring Data Commons. Make use of the newly introduced PersistentEntity.doWithAll(…) to apply the previously existing property handling to both properties and now associations, too.

Original pull request #938

Author: odrotbohm

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/core/convert/BasicJdbcConverter.java

@@ -183,7 +183,7 @@ public Class<?> getColumnType(RelationalPersistentProperty property) {
 
 	private Class<?> doGetColumnType(RelationalPersistentProperty property) {
 
-		if (property.isReference()) {
+		if (property.isAssociation()) {
 			return getReferenceColumnType(property);
 		}
 
@@ -419,23 +419,23 @@ private T populateProperties(T instance, @Nullable Object idValue) {
 			PersistentPropertyAccessor<T> propertyAccessor = getPropertyAccessor(entity, instance);
 			PreferredConstructor<T, RelationalPersistentProperty> persistenceConstructor = entity.getPersistenceConstructor();
 
-			for (RelationalPersistentProperty property : entity) {
+			entity.doWithAll(property -> {
 
 				if (persistenceConstructor != null && persistenceConstructor.isConstructorParameter(property)) {
-					continue;
+					return;
 				}
 
 				// skip absent simple properties
 				if (isSimpleProperty(property)) {
 
 					if (!propertyValueProvider.hasProperty(property)) {
-						continue;
+						return;
 					}
 				}
 
 				Object value = readOrLoadProperty(idValue, property);
 				propertyAccessor.setProperty(property, value);
-			}
+			});
 
 			return propertyAccessor.getBean();
 		}
@@ -513,7 +513,7 @@ private boolean hasInstanceValues(@Nullable Object idValue) {
 			for (RelationalPersistentProperty embeddedProperty : persistentEntity) {
 
 				// if the embedded contains Lists, Sets or Maps we consider it non-empty
-				if (embeddedProperty.isQualified() || embeddedProperty.isReference()) {
+				if (embeddedProperty.isQualified() || embeddedProperty.isAssociation()) {
 					return true;
 				}
 

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/core/convert/DefaultDataAccessStrategy.java

@@ -36,7 +36,6 @@
 import org.springframework.data.mapping.PersistentProperty;
 import org.springframework.data.mapping.PersistentPropertyAccessor;
 import org.springframework.data.mapping.PersistentPropertyPath;
-import org.springframework.data.mapping.PropertyHandler;
 import org.springframework.data.relational.core.dialect.IdGeneration;
 import org.springframework.data.relational.core.mapping.PersistentPropertyPathExtension;
 import org.springframework.data.relational.core.mapping.RelationalMappingContext;
@@ -424,7 +423,7 @@ private <S, T> SqlIdentifierParameterSource getParameterSource(@Nullable S insta
 		PersistentPropertyAccessor<S> propertyAccessor = instance != null ? persistentEntity.getPropertyAccessor(instance)
 				: NoValuePropertyAccessor.instance();
 
-		persistentEntity.doWithProperties((PropertyHandler<RelationalPersistentProperty>) property -> {
+		persistentEntity.doWithAll(property -> {
 
 			if (skipProperty.test(property) || !property.isWritable()) {
 				return;

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/core/convert/SqlGenerator.java

@@ -19,7 +19,6 @@
 import org.springframework.data.domain.Sort;
 import org.springframework.data.jdbc.repository.support.SimpleJdbcRepository;
 import org.springframework.data.mapping.PersistentPropertyPath;
-import org.springframework.data.mapping.PropertyHandler;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.relational.core.dialect.Dialect;
 import org.springframework.data.relational.core.dialect.RenderContextFactory;
@@ -818,7 +817,7 @@ static class Columns {
 
 		private void populateColumnNameCache(RelationalPersistentEntity<?> entity, String prefix) {
 
-			entity.doWithProperties((PropertyHandler<RelationalPersistentProperty>) property -> {
+			entity.doWithAll(property -> {
 
 				// the referencing column of referenced entity is expected to be on the other side of the relation
 				if (!property.isEntity()) {

spring-data-jdbc/src/main/java/org/springframework/data/jdbc/core/mapping/BasicJdbcPersistentProperty.java

@@ -60,9 +60,21 @@ public BasicJdbcPersistentProperty(Property property, PersistentEntity<?, Relati
 		super(property, owner, simpleTypeHolder, namingStrategy);
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.mapping.model.AnnotationBasedPersistentProperty#isAssociation()
+	 */
 	@Override
-	public boolean isReference() {
-		return AggregateReference.class.isAssignableFrom(getRawType());
+	public boolean isAssociation() {
+		return super.isAssociation() || AggregateReference.class.isAssignableFrom(getRawType());
 	}
 
+	/*
+	 * (non-Javadoc)
+	 * @see org.springframework.data.relational.core.mapping.BasicRelationalPersistentProperty#isReference()
+	 */
+	@Override
+	public boolean isReference() {
+		return isAssociation();
+	}
 }

spring-data-jdbc/src/test/java/org/springframework/data/jdbc/core/mapping/BasicJdbcPersistentPropertyUnitTests.java

@@ -95,6 +95,15 @@ public void detectsKeyColumnOverrideNameFromMappedCollectionAnnotation() {
 		assertThat(listProperty.getReverseColumnName(path)).isEqualTo(quoted("override_id"));
 	}
 
+	@Test // #938
+	void considersAggregateReferenceAnAssociation() {
+
+		RelationalPersistentEntity<?> entity = context.getRequiredPersistentEntity(WithAssociations.class);
+		RelationalPersistentProperty property = entity.getRequiredPersistentProperty("association");
+
+		assertThat(property.isAssociation()).isTrue();
+	}
+
 	private PersistentPropertyPathExtension getPersistentPropertyPath(Class<?> type, String propertyName) {
 		PersistentPropertyPath<RelationalPersistentProperty> path = context
 				.findPersistentPropertyPaths(type, p -> p.getName().equals(propertyName)).getFirst()
@@ -149,4 +158,8 @@ private static class WithCollections {
 		@MappedCollection(idColumn = "override_id", keyColumn = "override_key") //
 		List<Integer> overrideList;
 	}
+
+	static class WithAssociations {
+		AggregateReference<Object, Long> association;
+	}
 }

spring-data-relational/src/main/java/org/springframework/data/relational/core/mapping/BasicRelationalPersistentProperty.java

@@ -124,7 +124,7 @@ private SqlIdentifier createDerivedSqlIdentifier(String name) {
 	 */
 	@Override
 	protected Association<RelationalPersistentProperty> createAssociation() {
-		throw new UnsupportedOperationException();
+		return new Association<>(this, null);
 	}
 
 	public boolean isForceQuote() {
@@ -137,7 +137,7 @@ public void setForceQuote(boolean forceQuote) {
 
 	@Override
 	public boolean isEntity() {
-		return super.isEntity() && !isReference();
+		return super.isEntity() && !isAssociation();
 	}
 
 	@Override

spring-data-relational/src/main/java/org/springframework/data/relational/core/mapping/RelationalPersistentProperty.java

@@ -28,6 +28,11 @@
  */
 public interface RelationalPersistentProperty extends PersistentProperty<RelationalPersistentProperty> {
 
+	/**
+	 * @deprecated since 2.2, in favor of {@link #isAssociation()}
+	 * @return
+	 */
+	@Deprecated
 	boolean isReference();
 
 	/**