Merge branch '5.3.x'

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

@@ -854,6 +854,20 @@ public abstract class ClassUtils {
 		return (clazz.isMemberClass() && !isStaticClass(clazz));
 	}
 
+	/**
+	 * Determine if the supplied {@link Class} is a JVM-generated implementation
+	 * class for a lambda expression or method reference.
+	 * <p>This method makes a best-effort attempt at determining this, based on
+	 * checks that work on modern, mainstream JVMs.
+	 * @param clazz the class to check
+	 * @return {@code true} if the class is a lambda implementation class
+	 * @since 5.3.19
+	 */
+	public static boolean isLambdaClass(Class<?> clazz) {
+		return (clazz.isSynthetic() && (clazz.getSuperclass() == Object.class) &&
+				(clazz.getInterfaces().length > 0) && clazz.getName().contains("$$Lambda"));
+	}
+
 	/**
 	 * Check whether the given object is a CGLIB proxy.
 	 * @param object the object to check