diff --git a/src/Monolog/Handler/Handler.php b/src/Monolog/Handler/Handler.php
index e89f969b..8a4e7ab1 100644
--- a/src/Monolog/Handler/Handler.php
+++ b/src/Monolog/Handler/Handler.php
@@ -44,19 +44,10 @@ abstract class Handler implements HandlerInterface
         }
     }
 
-    public function __sleep()
+    public function __serialize(): array
     {
         $this->close();
 
-        $reflClass = new \ReflectionClass($this);
-
-        $keys = [];
-        foreach ($reflClass->getProperties() as $reflProp) {
-            if (!$reflProp->isStatic()) {
-                $keys[] = $reflProp->getName();
-            }
-        }
-
-        return $keys;
+        return (array) $this;
     }
 }
diff --git a/tests/Monolog/Handler/StreamHandlerTest.php b/tests/Monolog/Handler/StreamHandlerTest.php
index e2241234..bc47e8ed 100644
--- a/tests/Monolog/Handler/StreamHandlerTest.php
+++ b/tests/Monolog/Handler/StreamHandlerTest.php
@@ -67,7 +67,7 @@ class StreamHandlerTest extends \Monolog\Test\MonologTestCase
 
     /**
      * @covers Monolog\Handler\StreamHandler::close
-     * @covers Monolog\Handler\Handler::__sleep
+     * @covers Monolog\Handler\Handler::__serialize
      */
     public function testSerialization()
     {