diff --git a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataResource.java b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataResource.java
index 5da42de7796b..0b889e02a30f 100644
--- a/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataResource.java
+++ b/spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/config/StandardConfigDataResource.java
@@ -36,7 +36,7 @@ public class StandardConfigDataResource extends ConfigDataResource {
 
 	private final Resource resource;
 
-	private boolean emptyDirectory;
+	private final boolean emptyDirectory;
 
 	/**
 	 * Create a new {@link StandardConfigDataResource} instance.