diff --git a/src/main/kotlin/com/erikschouten/springjwtauthenticator/validator/Validator.kt b/src/main/kotlin/com/erikschouten/springjwtauthenticator/validator/Validator.kt
index dceff3e..92e6b2a 100644
--- a/src/main/kotlin/com/erikschouten/springjwtauthenticator/validator/Validator.kt
+++ b/src/main/kotlin/com/erikschouten/springjwtauthenticator/validator/Validator.kt
@@ -4,7 +4,7 @@ import org.springframework.security.core.userdetails.UserDetails
 import org.springframework.stereotype.Service
 
 @Service
-class Validator {
+open class Validator {
     @Throws(ValidationException::class)
-    fun validate(userDetails: UserDetails) {}
+    open fun validate(userDetails: UserDetails) {}
 }