From db4fbb32682a38dfb88e81e2872e923c1d8b3d94 Mon Sep 17 00:00:00 2001
From: Vadim Ponomarev <38704817+VxDxK@users.noreply.github.com>
Date: Wed, 16 Nov 2022 22:25:13 +0300
Subject: [PATCH] refactoring: Improve monad methods (#2300)

---
 monad/src/main/java/com/iluwatar/monad/Validator.java | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/monad/src/main/java/com/iluwatar/monad/Validator.java b/monad/src/main/java/com/iluwatar/monad/Validator.java
index 7d5440b73..757343e75 100644
--- a/monad/src/main/java/com/iluwatar/monad/Validator.java
+++ b/monad/src/main/java/com/iluwatar/monad/Validator.java
@@ -78,7 +78,7 @@ public class Validator<T> {
    * @param message    error message when object is invalid
    * @return this
    */
-  public Validator<T> validate(Predicate<T> validation, String message) {
+  public Validator<T> validate(Predicate<? super T> validation, String message) {
     if (!validation.test(obj)) {
       exceptions.add(new IllegalStateException(message));
     }
@@ -97,8 +97,8 @@ public class Validator<T> {
    * @return this
    */
   public <U> Validator<T> validate(
-      Function<T, U> projection,
-      Predicate<U> validation,
+      Function<? super T, ? extends U> projection,
+      Predicate<? super U> validation,
       String message
   ) {
     return validate(projection.andThen(validation::test)::apply, message);