diff --git a/spring-data-jpa/src/main/java/org/springframework/data/jpa/domain/PredicateSpecification.java b/spring-data-jpa/src/main/java/org/springframework/data/jpa/domain/PredicateSpecification.java
index dc17edbfc..5ed394ad1 100644
--- a/spring-data-jpa/src/main/java/org/springframework/data/jpa/domain/PredicateSpecification.java
+++ b/spring-data-jpa/src/main/java/org/springframework/data/jpa/domain/PredicateSpecification.java
@@ -40,6 +40,7 @@ import org.springframework.util.Assert;
  * @author Mark Paluch
  * @since 4.0
  */
+@FunctionalInterface
 public interface PredicateSpecification<T> extends Serializable {
 
 	/**
diff --git a/spring-data-jpa/src/test/java/org/springframework/data/jpa/domain/SpecificationUnitTests.java b/spring-data-jpa/src/test/java/org/springframework/data/jpa/domain/SpecificationUnitTests.java
index 83998fb19..8380816d5 100644
--- a/spring-data-jpa/src/test/java/org/springframework/data/jpa/domain/SpecificationUnitTests.java
+++ b/spring-data-jpa/src/test/java/org/springframework/data/jpa/domain/SpecificationUnitTests.java
@@ -88,7 +88,7 @@ class SpecificationUnitTests {
 
 		assertThat(specification).isNotNull();
 
-		@SuppressWarnings({ "unchecked", "deprecation" })
+		@SuppressWarnings({ "unchecked", "deprecation"})
 		Specification<Object> transferredSpecification = (Specification<Object>) deserialize(serialize(specification));
 
 		assertThat(transferredSpecification).isNotNull();
@@ -103,7 +103,7 @@ class SpecificationUnitTests {
 
 		assertThat(specification).isNotNull();
 
-		@SuppressWarnings({ "unchecked", "deprecation" })
+		@SuppressWarnings({ "unchecked", "deprecation"})
 		Specification<Object> transferredSpecification = (Specification<Object>) deserialize(serialize(specification));
 
 		assertThat(transferredSpecification).isNotNull();