CachedIntrospectionResults completely traverses interface hierarchy

Issue: SPR-16978

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

@@ -297,20 +297,10 @@ public final class CachedIntrospectionResults {
 
 			// Explicitly check implemented interfaces for setter/getter methods as well,
 			// in particular for Java 8 default methods...
-			Class<?> clazz = beanClass;
-			while (clazz != null && clazz != Object.class) {
-				Class<?>[] ifcs = clazz.getInterfaces();
-				for (Class<?> ifc : ifcs) {
-					if (!ClassUtils.isJavaLanguageInterface(ifc)) {
-						for (PropertyDescriptor pd : getBeanInfo(ifc).getPropertyDescriptors()) {
-							if (!this.propertyDescriptorCache.containsKey(pd.getName())) {
-								pd = buildGenericTypeAwarePropertyDescriptor(beanClass, pd);
-								this.propertyDescriptorCache.put(pd.getName(), pd);
-							}
-						}
-					}
-				}
-				clazz = clazz.getSuperclass();
+			Class<?> currClass = beanClass;
+			while (currClass != null && currClass != Object.class) {
+				introspectInterfaces(beanClass, currClass);
+				currClass = currClass.getSuperclass();
 			}
 
 			this.typeDescriptorCache = new ConcurrentReferenceHashMap<>();
@@ -320,6 +310,24 @@ public final class CachedIntrospectionResults {
 		}
 	}
 
+	private void introspectInterfaces(Class<?> beanClass, Class<?> currClass) throws IntrospectionException {
+		for (Class<?> ifc : currClass.getInterfaces()) {
+			if (!ClassUtils.isJavaLanguageInterface(ifc)) {
+				for (PropertyDescriptor pd : getBeanInfo(ifc).getPropertyDescriptors()) {
+					PropertyDescriptor existingPd = this.propertyDescriptorCache.get(pd.getName());
+					if (existingPd == null ||
+							(existingPd.getReadMethod() == null && pd.getReadMethod() != null)) {
+						// GenericTypeAwarePropertyDescriptor leniently resolves a set* write method
+						// against a declared read method, so we prefer read method descriptors here.
+						pd = buildGenericTypeAwarePropertyDescriptor(beanClass, pd);
+						this.propertyDescriptorCache.put(pd.getName(), pd);
+					}
+				}
+				introspectInterfaces(ifc, ifc);
+			}
+		}
+	}
+
 
 	BeanInfo getBeanInfo() {
 		return this.beanInfo;

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2016 the original author or authors.
+ * Copyright 2002-2018 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.
@@ -49,7 +49,8 @@ public class BeanWrapperTests extends AbstractPropertyAccessorTests {
 		GetterBean target = new GetterBean();
 		BeanWrapper accessor = createAccessor(target);
 		accessor.setPropertyValue("name", "tom");
-		assertTrue("Set name to tom", target.getName().equals("tom"));
+		assertEquals("tom", target.getAliasedName());
+		assertEquals("tom", accessor.getPropertyValue("aliasedName"));
 	}
 
 	@Test
@@ -58,7 +59,8 @@ public class BeanWrapperTests extends AbstractPropertyAccessorTests {
 		BeanWrapper accessor = createAccessor(target);
 		accessor.setExtractOldValueForEditor(true); // This will call the getter
 		accessor.setPropertyValue("name", "tom");
-		assertTrue("Set name to tom", target.getName().equals("tom"));
+		assertEquals("tom", target.getAliasedName());
+		assertEquals("tom", accessor.getPropertyValue("aliasedName"));
 	}
 
 	@Test
@@ -66,7 +68,8 @@ public class BeanWrapperTests extends AbstractPropertyAccessorTests {
 		GetterBean target = new GetterBean();
 		BeanWrapper accessor = createAccessor(target);
 		accessor.setPropertyValue("aliasedName", "tom");
-		assertTrue("Set name to tom", target.getAliasedName().equals("tom"));
+		assertEquals("tom", target.getAliasedName());
+		assertEquals("tom", accessor.getPropertyValue("aliasedName"));
 	}
 
 	@Test
@@ -216,20 +219,24 @@ public class BeanWrapperTests extends AbstractPropertyAccessorTests {
 	}
 
 
+	private interface BaseProperty {
+
+		default String getAliasedName() {
+			return getName();
+		}
+
+		String getName();
+	}
+
+
 	@SuppressWarnings("unused")
-	private interface AliasedProperty {
+	private interface AliasedProperty extends BaseProperty {
 
 		default void setAliasedName(String name) {
 			setName(name);
 		}
 
-		default String getAliasedName() {
-			return getName();
-		}
-
 		void setName(String name);
-
-		String getName();
 	}