diff --git a/.travis.yml b/.travis.yml
index 81e01afa..24d343a3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,9 +6,8 @@ addons:
       - git
 
 php:
-  - 7.1
-  - 7.2
   - 7.3
+  - 7.4
 
 jobs:
   fast_finish: true
@@ -34,13 +33,13 @@ install:
   # Disable xDebug (but do not remove its configuration, because we need that for code coverage calculation).
   # Clear the default 6 minutes max execution time limit otherwise test suite fails in case of online tests.
   - echo -en "max_execution_time = 0\nxdebug.default_enable = 0" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini
-  - composer self-update --1
-  - if [[ $(phpenv version-name) = "7.1" ]] || [[ $(phpenv version-name) = "7.2" ]]; then composer global require hirak/prestissimo:^0.3.7; fi
 
   - travis_retry composer update $COMPOSER_OPTIONS $DEPENDENCIES
+
+  - if [[ $(phpenv version-name) = "7.3" ]]; then composer require symfony/polyfill-mbstring:1.19.0 --update-with-dependencies $DEPENDENCIES; fi
+
   # Fix PHPUnit tests on PHP >= 7.2 by upgrading Guzzle to >= 6.3.0.
   # https://github.com/guzzle/guzzle/issues/1973
-  - if [[ $(phpenv version-name) = "7.2" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then composer require guzzlehttp/guzzle:^6.3.0 --update-with-dependencies $DEPENDENCIES; fi
   - if [[ $(phpenv version-name) = "7.3" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then composer require guzzlehttp/guzzle:^6.3.0 --update-with-dependencies $DEPENDENCIES; fi
   - if [[ $(phpenv version-name) = "7.4" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then composer require guzzlehttp/guzzle:^6.3.0 --update-with-dependencies $DEPENDENCIES; fi
   - composer show
@@ -55,8 +54,8 @@ script:
   - composer check-style -- --using-cache=no "${EXTRA_ARGS[@]}"
   - composer analyze
   # Only calculate metrics data for this specific build.
-  - if [[ $(phpenv version-name) = "7.1" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then composer test -- --coverage-clover=clover.xml; else composer test; fi
-  - if [[ $(phpenv version-name) = "7.1" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then composer metrics; fi
+  - if [[ $(phpenv version-name) = "7.4" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then composer test; fi
+  - if [[ $(phpenv version-name) = "7.4" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then composer metrics; fi
 
 after_success:
-  - if [[ $(phpenv version-name) = "7.1" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then bash <(curl -s https://codecov.io/bash) -f ./clover.xml; fi
+  - if [[ $(phpenv version-name) = "7.4" ]] && [[ "$DEPENDENCIES" = "--prefer-lowest" ]]; then bash <(curl -s https://codecov.io/bash) -f ./clover.xml; fi
diff --git a/composer.json b/composer.json
index 814d93ab..2bca72ea 100644
--- a/composer.json
+++ b/composer.json
@@ -31,29 +31,27 @@
         "symfony/options-resolver": "^3.4 || ^4.0",
         "symfony/property-access": "^3.4.41 || ^4.4.9",
         "symfony/property-info": "^3.4 || ^4.0",
-        "symfony/serializer": "^3.4 || ^4.0"
+        "symfony/serializer": "^4.4"
     },
     "require-dev": {
-        "friendsofphp/php-cs-fixer": "^2.16",
+        "friendsofphp/php-cs-fixer": "^2.19",
         "fzaninotto/faker": "^1.7",
         "guzzlehttp/psr7": "^1.0",
         "league/flysystem": "^1.0",
-        "limedeck/phpunit-detailed-printer": "^3.2",
+        "limedeck/phpunit-detailed-printer": "^4",
         "monolog/monolog": "^1.23",
         "php-http/guzzle6-adapter": "^2.0",
         "php-http/mock-client": "^1.1.0",
         "phpmetrics/phpmetrics": "^2.3",
-        "phpunit/phpunit": "^6.4.0",
-        "sebastian/comparator": "^2.1",
+        "phpunit/phpunit": "^7.5.20",
+        "sebastian/comparator": "^3.0.3",
         "symfony/cache": "~3.4 || ~4.0",
-        "vimeo/psalm": "^2.0.0"
+        "vimeo/psalm": "^3.18.2"
     },
     "conflict": {
         "guzzlehttp/guzzle": "<6.1.0",
         "guzzlehttp/psr7": "<1.4.1",
-        "phpdocumentor/type-resolver": "<0.2.1",
-        "vimeo/psalm": ">2.0.13",
-        "symfony/polyfill-mbstring": ">1.20.0"
+        "phpdocumentor/type-resolver": "<0.2.1"
     },
     "autoload": {
         "psr-4": {
diff --git a/psalm.xml.dist b/psalm.xml.dist
index 11e2e816..0c31e235 100644
--- a/psalm.xml.dist
+++ b/psalm.xml.dist
@@ -3,6 +3,8 @@
     name="Apigee Edge PHP API client default configuration"
     totallyTyped="false"
     useDocblockTypes="true"
+    memoizeMethodCallResults="true"
+    allowStringToStandInForClass="true"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns="https://getpsalm.org/schema/config"
     xsi:schemaLocation="https://getpsalm.org/schema/config file:///var/www/html/vendor/vimeo/psalm/config.xsd"
diff --git a/src/Api/ApigeeX/Controller/ApiProductController.php b/src/Api/ApigeeX/Controller/ApiProductController.php
index bc01500e..ad51b2c3 100755
--- a/src/Api/ApigeeX/Controller/ApiProductController.php
+++ b/src/Api/ApigeeX/Controller/ApiProductController.php
@@ -134,7 +134,7 @@ private function getEligibleProducts(string $type, string $entityId): array
             }
         }
 
-        $current_ms = substr(microtime(true) * 1000, 0);
+        $current_ms = substr((string) (microtime(true) * 1000), 0);
 
         foreach ($this->getAvailablexApiProducts($type, $entityId, true) as $item) {
             // Create a new rate plan controller.
diff --git a/src/Api/ApigeeX/Denormalizer/AcceptedRatePlanDenormalizer.php b/src/Api/ApigeeX/Denormalizer/AcceptedRatePlanDenormalizer.php
index 2267b386..4157aca0 100755
--- a/src/Api/ApigeeX/Denormalizer/AcceptedRatePlanDenormalizer.php
+++ b/src/Api/ApigeeX/Denormalizer/AcceptedRatePlanDenormalizer.php
@@ -32,10 +32,10 @@ abstract class AcceptedRatePlanDenormalizer extends ObjectDenormalizer
      * @psalm-suppress PossiblyNullReference - getPackage() can only return
      * null when a rate plan is created. It does not return null here.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         /** @var \Apigee\Edge\Api\ApigeeX\Entity\AcceptedRatePlanInterface $denormalized */
-        $denormalized = parent::denormalize($data, $class, $format, $context);
+        $denormalized = parent::denormalize($data, $type, $format, $context);
 
         return $denormalized;
     }
diff --git a/src/Api/ApigeeX/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php b/src/Api/ApigeeX/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php
index 171f04f6..d76f95fd 100755
--- a/src/Api/ApigeeX/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php
+++ b/src/Api/ApigeeX/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php
@@ -32,7 +32,7 @@ class DeveloperAcceptedRatePlanDenormalizer extends AcceptedRatePlanDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return parent::denormalize($data, $this->developerAcceptedRatePlanClass, $format, $context);
     }
diff --git a/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizer.php b/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizer.php
index a7a0acd3..93d3dc5b 100755
--- a/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizer.php
+++ b/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizer.php
@@ -54,10 +54,10 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
      * @psalm-suppress PossiblyNullReference - Organization should not be null
      * here.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         /** @var \Apigee\Edge\Api\ApigeeX\Entity\RatePlanInterface $entity */
-        $entity = parent::denormalize($data, $class, $format, $context);
+        $entity = parent::denormalize($data, $type, $format, $context);
 
         return $entity;
     }
diff --git a/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizerFactory.php b/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizerFactory.php
index ffad4dd2..066f3a8d 100755
--- a/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizerFactory.php
+++ b/src/Api/ApigeeX/Denormalizer/RatePlanDenormalizerFactory.php
@@ -56,13 +56,13 @@ public function __construct(array $denormalizers = [])
      * @psalm-suppress InvalidNullableReturnType - There are going to be at
      * least one denormalizer always that can denormalize data here.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         foreach ($this->denormalizers as $denormalizer) {
             // Return the result from the first denormalizer that can
             // denormalize this.
-            if ($denormalizer->supportsDenormalization($data, $class, $format)) {
-                return $denormalizer->denormalize($data, $class, $format, $context);
+            if ($denormalizer->supportsDenormalization($data, $type, $format)) {
+                return $denormalizer->denormalize($data, $type, $format, $context);
             }
         }
     }
diff --git a/src/Api/ApigeeX/Denormalizer/RatePlanRateDenormalizer.php b/src/Api/ApigeeX/Denormalizer/RatePlanRateDenormalizer.php
index 2a18296e..434a60e5 100755
--- a/src/Api/ApigeeX/Denormalizer/RatePlanRateDenormalizer.php
+++ b/src/Api/ApigeeX/Denormalizer/RatePlanRateDenormalizer.php
@@ -33,7 +33,7 @@ class RatePlanRateDenormalizer extends ObjectDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         $denormalized = (array) $data;
         if (RatePlanRate::TYPE_REVSHARE === $data->type) {
diff --git a/src/Api/ApigeeX/Denormalizer/StandardRatePlanDenormalizer.php b/src/Api/ApigeeX/Denormalizer/StandardRatePlanDenormalizer.php
index 063985cc..0437fe1f 100755
--- a/src/Api/ApigeeX/Denormalizer/StandardRatePlanDenormalizer.php
+++ b/src/Api/ApigeeX/Denormalizer/StandardRatePlanDenormalizer.php
@@ -41,7 +41,7 @@ class StandardRatePlanDenormalizer extends RatePlanDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if (isset($data->parentRatePlan)) {
             return parent::denormalize($data, $this->standardRatePlanRevisionClass, $format, $context);
diff --git a/src/Api/ApigeeX/Entity/AcceptedRatePlanInterface.php b/src/Api/ApigeeX/Entity/AcceptedRatePlanInterface.php
index 35e4ecbc..4b863d6e 100755
--- a/src/Api/ApigeeX/Entity/AcceptedRatePlanInterface.php
+++ b/src/Api/ApigeeX/Entity/AcceptedRatePlanInterface.php
@@ -18,6 +18,7 @@
 
 namespace Apigee\Edge\Api\ApigeeX\Entity;
 
+use Apigee\Edge\Api\ApigeeX\Entity\Property\ApiProductPropertyInterface;
 use Apigee\Edge\Api\ApigeeX\Entity\Property\EndTimePropertyInterface;
 use Apigee\Edge\Api\ApigeeX\Entity\Property\StartTimePropertyInterface;
 use Apigee\Edge\Api\Monetization\Entity\EntityInterface;
@@ -27,6 +28,7 @@ interface AcceptedRatePlanInterface extends
     EntityInterface,
     EndTimePropertyInterface,
     StartTimePropertyInterface,
+    ApiProductPropertyInterface,
     NamePropertyInterface
 {
     /**
diff --git a/src/Api/ApigeeX/Entity/RatePlanInterface.php b/src/Api/ApigeeX/Entity/RatePlanInterface.php
index 177144a7..03ff093f 100755
--- a/src/Api/ApigeeX/Entity/RatePlanInterface.php
+++ b/src/Api/ApigeeX/Entity/RatePlanInterface.php
@@ -19,6 +19,7 @@
 namespace Apigee\Edge\Api\ApigeeX\Entity;
 
 use Apigee\Edge\Api\ApigeeX\Entity\Property\ApiProductPropertyInterface;
+use Apigee\Edge\Api\ApigeeX\Entity\Property\EndTimePropertyInterface;
 use Apigee\Edge\Api\ApigeeX\Structure\ConsumptionPricingRate;
 use Apigee\Edge\Api\ApigeeX\Structure\FixedRecurringFee;
 use Apigee\Edge\Api\ApigeeX\Structure\RatePlanXFee;
@@ -33,6 +34,7 @@ interface RatePlanInterface extends
     DescriptionPropertyInterface,
     DisplayNamePropertyInterface,
     ApiProductPropertyInterface,
+    EndTimePropertyInterface,
     NamePropertyInterface
 {
     public const FREQUENCY_DURATION_DAY = 'DAY';
diff --git a/src/Api/ApigeeX/Normalizer/RatePlanNormalizer.php b/src/Api/ApigeeX/Normalizer/RatePlanNormalizer.php
index 3fcac97d..c369fe0f 100755
--- a/src/Api/ApigeeX/Normalizer/RatePlanNormalizer.php
+++ b/src/Api/ApigeeX/Normalizer/RatePlanNormalizer.php
@@ -64,12 +64,6 @@ public function normalize($object, $format = null, array $context = [])
             throw new UninitializedPropertyException($object, 'package', 'Apigee\Edge\Api\ApigeeX\Entity\ApiProductInterface');
         }
 
-        if (null === $object->getPackage()->getOrganization()) {
-            throw new UninitializedPropertyException($object->getPackage(), 'organization', 'Apigee\Edge\Api\Monetization\Entity\OrganizationProfileInterface');
-        }
-
-        //$this->fixTimeZoneOnNormalization($object, $normalized, $object->getPackage()->getOrganization()->getTimezone());
-
         return $normalized;
     }
 
diff --git a/src/Api/Management/Controller/AppCredentialControllerInterface.php b/src/Api/Management/Controller/AppCredentialControllerInterface.php
index 345d1429..78a80838 100644
--- a/src/Api/Management/Controller/AppCredentialControllerInterface.php
+++ b/src/Api/Management/Controller/AppCredentialControllerInterface.php
@@ -104,10 +104,11 @@ public function addProducts(string $consumerKey, array $apiProducts): AppCredent
      *
      * @see https://docs.apigee.com/management/apis/post/organizations/%7Borg_name%7D/developers/%7Bdeveloper_email_or_id%7D/apps/%7Bapp_name%7D/keys/%7Bconsumer_key%7D-0
      *
-     * @param string $consumerKey
+     * @param string $entityId
+     *   The consumer key
      * @param string $status
      */
-    public function setStatus(string $consumerKey, string $status): void;
+    public function setStatus(string $entityId, string $status): void;
 
     /**
      * Approve or revoke API product for an API key.
diff --git a/src/Api/Management/Denormalizer/AppDenormalizer.php b/src/Api/Management/Denormalizer/AppDenormalizer.php
index ce9c287f..8d8c95ff 100644
--- a/src/Api/Management/Denormalizer/AppDenormalizer.php
+++ b/src/Api/Management/Denormalizer/AppDenormalizer.php
@@ -46,7 +46,7 @@ class AppDenormalizer extends ObjectDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if (isset($data->developerId)) {
             return parent::denormalize($data, $this->developerAppClass, $format, $context);
diff --git a/src/Api/Management/Denormalizer/CompanyMembershipDenormalizer.php b/src/Api/Management/Denormalizer/CompanyMembershipDenormalizer.php
index 8fa5cf0a..42b3f38a 100755
--- a/src/Api/Management/Denormalizer/CompanyMembershipDenormalizer.php
+++ b/src/Api/Management/Denormalizer/CompanyMembershipDenormalizer.php
@@ -29,7 +29,7 @@ class CompanyMembershipDenormalizer implements DenormalizerInterface
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         $denormalized = [];
         // Ignore parent "developer" key.
diff --git a/src/Api/Monetization/Controller/EntityListingControllerAwareTrait.php b/src/Api/Monetization/Controller/EntityListingControllerAwareTrait.php
index 194c2764..0838245f 100644
--- a/src/Api/Monetization/Controller/EntityListingControllerAwareTrait.php
+++ b/src/Api/Monetization/Controller/EntityListingControllerAwareTrait.php
@@ -32,6 +32,8 @@ trait EntityListingControllerAwareTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Entity\EntityInterface[]
      */
     public function getEntities(): array
     {
diff --git a/src/Api/Monetization/Controller/FilteredReportDefinitionsTrait.php b/src/Api/Monetization/Controller/FilteredReportDefinitionsTrait.php
index c282650e..b7ebfe8a 100644
--- a/src/Api/Monetization/Controller/FilteredReportDefinitionsTrait.php
+++ b/src/Api/Monetization/Controller/FilteredReportDefinitionsTrait.php
@@ -27,6 +27,8 @@ trait FilteredReportDefinitionsTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Api\Monetization\Entity\ReportDefinitionInterface[]
      */
     public function getFilteredEntities(int $limit = null, int $page = 1, string $sort = null): array
     {
diff --git a/src/Api/Monetization/Controller/LegalEntityTermsAndConditionsController.php b/src/Api/Monetization/Controller/LegalEntityTermsAndConditionsController.php
index 7ba94a57..9bf9642b 100644
--- a/src/Api/Monetization/Controller/LegalEntityTermsAndConditionsController.php
+++ b/src/Api/Monetization/Controller/LegalEntityTermsAndConditionsController.php
@@ -33,7 +33,7 @@ abstract class LegalEntityTermsAndConditionsController extends OrganizationAware
 {
     use EntityListingControllerTrait;
     use ListingHelperTrait {
-        responseArrayToArrayOfEntities as private traitResponseArrayToArrayOfEntities;
+        EntityListingControllerTrait::responseArrayToArrayOfEntities as private traitResponseArrayToArrayOfEntities;
     }
 
     /**
diff --git a/src/Api/Monetization/Controller/PaginatedEntityListingControllerAwareTrait.php b/src/Api/Monetization/Controller/PaginatedEntityListingControllerAwareTrait.php
index d8311122..f47e2871 100644
--- a/src/Api/Monetization/Controller/PaginatedEntityListingControllerAwareTrait.php
+++ b/src/Api/Monetization/Controller/PaginatedEntityListingControllerAwareTrait.php
@@ -31,6 +31,8 @@ trait PaginatedEntityListingControllerAwareTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Entity\EntityInterface[]
      */
     public function getEntities(): array
     {
@@ -39,6 +41,8 @@ public function getEntities(): array
 
     /**
      * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Entity\EntityInterface[]
      */
     public function getPaginatedEntityList(int $limit = null, int $page = 1): array
     {
diff --git a/src/Api/Monetization/Denormalizer/AcceptedRatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/AcceptedRatePlanDenormalizer.php
index 8dbe865a..7945c138 100644
--- a/src/Api/Monetization/Denormalizer/AcceptedRatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/AcceptedRatePlanDenormalizer.php
@@ -32,10 +32,10 @@ abstract class AcceptedRatePlanDenormalizer extends ObjectDenormalizer
      * @psalm-suppress PossiblyNullReference - getPackage() can only return
      * null when a rate plan is created. It does not return null here.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         /** @var \Apigee\Edge\Api\Monetization\Entity\AcceptedRatePlanInterface $denormalized */
-        $denormalized = parent::denormalize($data, $class, $format, $context);
+        $denormalized = parent::denormalize($data, $type, $format, $context);
 
         $this->fixTimeZoneOnDenormalization($data, $denormalized, $denormalized->getRatePlan()->getPackage()->getOrganization()->getTimezone());
 
diff --git a/src/Api/Monetization/Denormalizer/CompanyAcceptedRatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/CompanyAcceptedRatePlanDenormalizer.php
index 0d5745b6..42e1e2da 100644
--- a/src/Api/Monetization/Denormalizer/CompanyAcceptedRatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/CompanyAcceptedRatePlanDenormalizer.php
@@ -51,7 +51,7 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return parent::denormalize($data, $this->companyAcceptedRatePlanClass, $format, $context);
     }
diff --git a/src/Api/Monetization/Denormalizer/CompanyPaymentTransactionDenormalizer.php b/src/Api/Monetization/Denormalizer/CompanyPaymentTransactionDenormalizer.php
index 8c47558f..7339a7d8 100644
--- a/src/Api/Monetization/Denormalizer/CompanyPaymentTransactionDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/CompanyPaymentTransactionDenormalizer.php
@@ -51,7 +51,7 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return parent::denormalize($data, $this->companyPaymentTransactionClass, $format, $context);
     }
diff --git a/src/Api/Monetization/Denormalizer/CompanyRatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/CompanyRatePlanDenormalizer.php
index 7153b374..2f624b8a 100644
--- a/src/Api/Monetization/Denormalizer/CompanyRatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/CompanyRatePlanDenormalizer.php
@@ -56,7 +56,7 @@ public function __construct(?\Symfony\Component\Serializer\Mapping\Factory\Class
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if (isset($data->parentRatePlan)) {
             return parent::denormalize($data, $this->companyRatePlanRevisionClass, $format, $context);
diff --git a/src/Api/Monetization/Denormalizer/CompanyReportDefinitionDenormalizer.php b/src/Api/Monetization/Denormalizer/CompanyReportDefinitionDenormalizer.php
index acf2e555..9c52f55d 100644
--- a/src/Api/Monetization/Denormalizer/CompanyReportDefinitionDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/CompanyReportDefinitionDenormalizer.php
@@ -51,7 +51,7 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return parent::denormalize($data, $this->companyReportDefinitionClass, $format, $context);
     }
diff --git a/src/Api/Monetization/Denormalizer/DateTimeZoneDenormalizer.php b/src/Api/Monetization/Denormalizer/DateTimeZoneDenormalizer.php
index 6d326928..3f91ed78 100644
--- a/src/Api/Monetization/Denormalizer/DateTimeZoneDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/DateTimeZoneDenormalizer.php
@@ -27,12 +27,12 @@ class DateTimeZoneDenormalizer implements DenormalizerInterface
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         try {
             return new DateTimeZone($data);
         } catch (\Exception $e) {
-            throw new UnexpectedValueException(sprintf('"%s" is not a valid timezone.', $data), $e->getCode(), $e);
+            throw new UnexpectedValueException(sprintf('"%s" is not a valid timezone.', $data), (int) $e->getCode(), $e);
         }
     }
 
diff --git a/src/Api/Monetization/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php
index 73f6503c..186a4e84 100644
--- a/src/Api/Monetization/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/DeveloperAcceptedRatePlanDenormalizer.php
@@ -32,7 +32,7 @@ class DeveloperAcceptedRatePlanDenormalizer extends AcceptedRatePlanDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return parent::denormalize($data, $this->developerAcceptedRatePlanClass, $format, $context);
     }
diff --git a/src/Api/Monetization/Denormalizer/DeveloperCategoryRatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/DeveloperCategoryRatePlanDenormalizer.php
index 7a5b2df2..a6214ad1 100644
--- a/src/Api/Monetization/Denormalizer/DeveloperCategoryRatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/DeveloperCategoryRatePlanDenormalizer.php
@@ -41,7 +41,7 @@ class DeveloperCategoryRatePlanDenormalizer extends RatePlanDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if (isset($data->parentRatePlan)) {
             return parent::denormalize($data, $this->developerCategoryRatePlanRevisionClass, $format, $context);
diff --git a/src/Api/Monetization/Denormalizer/DeveloperPaymentTransactionDenormalizer.php b/src/Api/Monetization/Denormalizer/DeveloperPaymentTransactionDenormalizer.php
index 13b434c1..e0bdcb5a 100644
--- a/src/Api/Monetization/Denormalizer/DeveloperPaymentTransactionDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/DeveloperPaymentTransactionDenormalizer.php
@@ -32,7 +32,7 @@ class DeveloperPaymentTransactionDenormalizer extends PaymentTransactionDenormal
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return parent::denormalize($data, $this->developerPaymentTransactionClass, $format, $context);
     }
diff --git a/src/Api/Monetization/Denormalizer/DeveloperRatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/DeveloperRatePlanDenormalizer.php
index 2fcbe70b..2607fb88 100644
--- a/src/Api/Monetization/Denormalizer/DeveloperRatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/DeveloperRatePlanDenormalizer.php
@@ -41,7 +41,7 @@ class DeveloperRatePlanDenormalizer extends RatePlanDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if (isset($data->parentRatePlan)) {
             return parent::denormalize($data, $this->developerRatePlanRevisionClass, $format, $context);
diff --git a/src/Api/Monetization/Denormalizer/DeveloperReportDefinitionDenormalizer.php b/src/Api/Monetization/Denormalizer/DeveloperReportDefinitionDenormalizer.php
index 44467328..dc039b49 100644
--- a/src/Api/Monetization/Denormalizer/DeveloperReportDefinitionDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/DeveloperReportDefinitionDenormalizer.php
@@ -32,7 +32,7 @@ class DeveloperReportDefinitionDenormalizer extends ReportDefinitionDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return parent::denormalize($data, $this->developerReportDefinitionClass, $format, $context);
     }
diff --git a/src/Api/Monetization/Denormalizer/LegalEntityDenormalizer.php b/src/Api/Monetization/Denormalizer/LegalEntityDenormalizer.php
index b0dd33e2..db7257b5 100644
--- a/src/Api/Monetization/Denormalizer/LegalEntityDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/LegalEntityDenormalizer.php
@@ -64,7 +64,7 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if ($data->isCompany) {
             return parent::denormalize($data, $this->companyClass, $format, $context);
diff --git a/src/Api/Monetization/Denormalizer/RatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/RatePlanDenormalizer.php
index 73b6123e..cd8a15e0 100644
--- a/src/Api/Monetization/Denormalizer/RatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/RatePlanDenormalizer.php
@@ -54,10 +54,10 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
      * @psalm-suppress PossiblyNullReference - Organization should not be null
      * here.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         /** @var \Apigee\Edge\Api\Monetization\Entity\RatePlanInterface $entity */
-        $entity = parent::denormalize($data, $class, $format, $context);
+        $entity = parent::denormalize($data, $type, $format, $context);
 
         $this->fixTimeZoneOnDenormalization($data, $entity, $entity->getOrganization()->getTimezone());
 
diff --git a/src/Api/Monetization/Denormalizer/RatePlanDenormalizerFactory.php b/src/Api/Monetization/Denormalizer/RatePlanDenormalizerFactory.php
index 8d34995c..035e97c8 100644
--- a/src/Api/Monetization/Denormalizer/RatePlanDenormalizerFactory.php
+++ b/src/Api/Monetization/Denormalizer/RatePlanDenormalizerFactory.php
@@ -53,13 +53,13 @@ public function __construct(array $denormalizers = [])
      * @psalm-suppress InvalidNullableReturnType - There are going to be at
      * least one denormalizer always that can denormalize data here.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         foreach ($this->denormalizers as $denormalizer) {
             // Return the result from the first denormalizer that can
             // denormalize this.
-            if ($denormalizer->supportsDenormalization($data, $class, $format)) {
-                return $denormalizer->denormalize($data, $class, $format, $context);
+            if ($denormalizer->supportsDenormalization($data, $type, $format)) {
+                return $denormalizer->denormalize($data, $type, $format, $context);
             }
         }
     }
diff --git a/src/Api/Monetization/Denormalizer/RatePlanRateDenormalizer.php b/src/Api/Monetization/Denormalizer/RatePlanRateDenormalizer.php
index 6cf0d38e..5030afa4 100644
--- a/src/Api/Monetization/Denormalizer/RatePlanRateDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/RatePlanRateDenormalizer.php
@@ -33,7 +33,7 @@ class RatePlanRateDenormalizer extends ObjectDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         $denormalized = (array) $data;
         if (RatePlanRate::TYPE_REVSHARE === $data->type) {
diff --git a/src/Api/Monetization/Denormalizer/ReportCriteriaDenormalizer.php b/src/Api/Monetization/Denormalizer/ReportCriteriaDenormalizer.php
index 5f45dc50..f79f7661 100644
--- a/src/Api/Monetization/Denormalizer/ReportCriteriaDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/ReportCriteriaDenormalizer.php
@@ -60,7 +60,7 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
      *
      * @psalm-suppress PossiblyInvalidArgument We are sure of the return type of denormalize().
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         // This is what is in the type-hint on the $criteria property of the
         // ReportDefinition object.
@@ -68,16 +68,16 @@ public function denormalize($data, $class, $format = null, array $context = [])
         // available in symfony/serializer > 4.1 therefore we have to use a
         // workaround here.
         // https://symfony.com/doc/master/components/serializer.html#serializing-interfaces-and-abstract-classes
-        if (AbstractCriteria::class === $class && isset($context[static::CONTEXT_REPORT_DEFINITION_TYPE])) {
+        if (AbstractCriteria::class === $type && isset($context[static::CONTEXT_REPORT_DEFINITION_TYPE])) {
             switch ($context[static::CONTEXT_REPORT_DEFINITION_TYPE]) {
                 case ReportDefinitionInterface::TYPE_BILLING:
-                    $class = BillingReportCriteria::class;
+                    $type = BillingReportCriteria::class;
                     break;
                 case ReportDefinitionInterface::TYPE_PREPAID_BALANCE:
-                    $class = PrepaidBalanceReportCriteria::class;
+                    $type = PrepaidBalanceReportCriteria::class;
                     break;
                 case ReportDefinitionInterface::TYPE_REVENUE:
-                    $class = RevenueReportCriteria::class;
+                    $type = RevenueReportCriteria::class;
                     break;
 
                 default:
@@ -115,7 +115,7 @@ public function denormalize($data, $class, $format = null, array $context = [])
             $data->productIds = array_unique($data->productIds);
         }
 
-        $denormalized = parent::denormalize($data, $class, $format, $context);
+        $denormalized = parent::denormalize($data, $type, $format, $context);
 
         // According to the API documentation it is always UTC.
         // https://docs.apigee.com/api-platform/monetization/create-reports#createreportdefapi
diff --git a/src/Api/Monetization/Denormalizer/StandardRatePlanDenormalizer.php b/src/Api/Monetization/Denormalizer/StandardRatePlanDenormalizer.php
index aad55091..44ebdb87 100644
--- a/src/Api/Monetization/Denormalizer/StandardRatePlanDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/StandardRatePlanDenormalizer.php
@@ -41,7 +41,7 @@ class StandardRatePlanDenormalizer extends RatePlanDenormalizer
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if (isset($data->parentRatePlan)) {
             return parent::denormalize($data, $this->standardRatePlanRevisionClass, $format, $context);
diff --git a/src/Api/Monetization/Denormalizer/TermsAndConditionsDenormalizer.php b/src/Api/Monetization/Denormalizer/TermsAndConditionsDenormalizer.php
index 84235a3b..c12eff05 100644
--- a/src/Api/Monetization/Denormalizer/TermsAndConditionsDenormalizer.php
+++ b/src/Api/Monetization/Denormalizer/TermsAndConditionsDenormalizer.php
@@ -51,10 +51,10 @@ public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory
      * @psalm-suppress PossiblyNullReference - Organization should not be null
      * here.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         /** @var \Apigee\Edge\Api\Monetization\Entity\TermsAndConditionsInterface $entity */
-        $entity = parent::denormalize($data, $class, $format, $context);
+        $entity = parent::denormalize($data, $type, $format, $context);
 
         $this->fixTimeZoneOnDenormalization($data, $entity, $entity->getOrganization()->getTimezone());
 
diff --git a/src/Api/Monetization/Entity/Property/AddressesPropertyAwareTrait.php b/src/Api/Monetization/Entity/Property/AddressesPropertyAwareTrait.php
index 7b9c6715..472abd2e 100644
--- a/src/Api/Monetization/Entity/Property/AddressesPropertyAwareTrait.php
+++ b/src/Api/Monetization/Entity/Property/AddressesPropertyAwareTrait.php
@@ -31,7 +31,9 @@ trait AddressesPropertyAwareTrait
     protected $addresses = [];
 
     /**
-     * @@inheritdoc
+     * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Api\Monetization\Structure\Address[]
      */
     public function getAddresses(): array
     {
@@ -39,7 +41,7 @@ public function getAddresses(): array
     }
 
     /**
-     * @@inheritdoc
+     * {@inheritdoc}
      */
     public function setAddresses(Address ...$addresses): void
     {
diff --git a/src/Api/Monetization/Entity/Property/ApiProductsPropertyAwareTrait.php b/src/Api/Monetization/Entity/Property/ApiProductsPropertyAwareTrait.php
index 31cd172c..b03dd283 100644
--- a/src/Api/Monetization/Entity/Property/ApiProductsPropertyAwareTrait.php
+++ b/src/Api/Monetization/Entity/Property/ApiProductsPropertyAwareTrait.php
@@ -32,6 +32,8 @@ trait ApiProductsPropertyAwareTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Api\Monetization\Entity\ApiProductInterface[]
      */
     public function getApiProducts(): array
     {
diff --git a/src/Api/Monetization/Serializer/ReportDefinitionSerializer.php b/src/Api/Monetization/Serializer/ReportDefinitionSerializer.php
index 4617f7bd..d04d17e7 100644
--- a/src/Api/Monetization/Serializer/ReportDefinitionSerializer.php
+++ b/src/Api/Monetization/Serializer/ReportDefinitionSerializer.php
@@ -84,11 +84,11 @@ public function deserialize($data, $type, $format, array $context = [])
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         $this->addReportDefinitionTypeToContext($data, $context);
 
-        return parent::denormalize($data, $class, $format, $context);
+        return parent::denormalize($data, $type, $format, $context);
     }
 
     /**
diff --git a/src/Client.php b/src/Client.php
index d3344666..18e8e2c5 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -169,7 +169,7 @@ public function getEndpoint(): string
     /**
      * {@inheritdoc}
      */
-    public function getUserAgent(): string
+    public function getUserAgent(): ?string
     {
         if (null !== $this->userAgentPrefix) {
             return sprintf("{$this->userAgentPrefix} ({$this->getClientVersion()})");
diff --git a/src/Controller/NonPaginatedEntityListingControllerTrait.php b/src/Controller/NonPaginatedEntityListingControllerTrait.php
index 993a0001..807302b5 100644
--- a/src/Controller/NonPaginatedEntityListingControllerTrait.php
+++ b/src/Controller/NonPaginatedEntityListingControllerTrait.php
@@ -32,6 +32,8 @@ trait NonPaginatedEntityListingControllerTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Entity\EntityInterface[]
      */
     public function getEntities(): array
     {
diff --git a/src/Controller/PaginatedEntityListingControllerTrait.php b/src/Controller/PaginatedEntityListingControllerTrait.php
index 3d7d95be..bba35ed2 100644
--- a/src/Controller/PaginatedEntityListingControllerTrait.php
+++ b/src/Controller/PaginatedEntityListingControllerTrait.php
@@ -29,6 +29,8 @@ trait PaginatedEntityListingControllerTrait
 {
     /**
      * {@inheritdoc}
+     *
+     * @return \Apigee\Edge\Entity\EntityInterface[]
      */
     public function getEntities(PagerInterface $pager = null, string $key_provider = 'id'): array
     {
diff --git a/src/Denormalizer/AttributesPropertyDenormalizer.php b/src/Denormalizer/AttributesPropertyDenormalizer.php
index 94b86888..90299901 100644
--- a/src/Denormalizer/AttributesPropertyDenormalizer.php
+++ b/src/Denormalizer/AttributesPropertyDenormalizer.php
@@ -48,7 +48,7 @@ public function supportsDenormalization($data, $type, $format = null)
      *
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         $flatten = [];
         foreach ($data as $key => $item) {
@@ -61,6 +61,6 @@ public function denormalize($data, $class, $format = null, array $context = [])
         }
         $data = $flatten;
 
-        return parent::denormalize($data, $class, $format, $context);
+        return parent::denormalize($data, $type, $format, $context);
     }
 }
diff --git a/src/Denormalizer/CredentialProductDenormalizer.php b/src/Denormalizer/CredentialProductDenormalizer.php
index 4777bc83..34dd0440 100644
--- a/src/Denormalizer/CredentialProductDenormalizer.php
+++ b/src/Denormalizer/CredentialProductDenormalizer.php
@@ -43,7 +43,7 @@ public function supportsDenormalization($data, $type, $format = null)
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         return new CredentialProduct($data->apiproduct, $data->status);
     }
diff --git a/src/Denormalizer/EdgeDateDenormalizer.php b/src/Denormalizer/EdgeDateDenormalizer.php
index 5f6e4591..3a5ae6df 100644
--- a/src/Denormalizer/EdgeDateDenormalizer.php
+++ b/src/Denormalizer/EdgeDateDenormalizer.php
@@ -51,7 +51,7 @@ public function __construct()
      * @psalm-suppress ImplementedReturnTypeMismatch - We have to return null,
      * even if it not officially supported by the overridden class.
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         // Handle -1 in expiresAt property of AppCredential.
         if ($data < 0) {
@@ -60,7 +60,7 @@ public function denormalize($data, $class, $format = null, array $context = [])
         $context[$this->normalizer::FORMAT_KEY] = 'U';
         $context[$this->normalizer::TIMEZONE_KEY] = new \DateTimeZone('UTC');
 
-        return $this->normalizer->denormalize(intval($data / 1000), $class, $format, $context);
+        return $this->normalizer->denormalize(intval($data / 1000), $type, $format, $context);
     }
 
     /**
diff --git a/src/Denormalizer/KeyValueMapDenormalizer.php b/src/Denormalizer/KeyValueMapDenormalizer.php
index 0213ccd1..af17052b 100644
--- a/src/Denormalizer/KeyValueMapDenormalizer.php
+++ b/src/Denormalizer/KeyValueMapDenormalizer.php
@@ -29,9 +29,9 @@ class KeyValueMapDenormalizer implements DenormalizerInterface
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
-        return new $class($data);
+        return new $type($data);
     }
 
     /**
diff --git a/src/Denormalizer/ObjectDenormalizer.php b/src/Denormalizer/ObjectDenormalizer.php
index e1cc87c9..43acb4b4 100644
--- a/src/Denormalizer/ObjectDenormalizer.php
+++ b/src/Denormalizer/ObjectDenormalizer.php
@@ -90,7 +90,7 @@ public function __construct(ClassMetadataFactoryInterface $classMetadataFactory
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         // The original input should not be altered.
         if (is_object($data)) {
@@ -108,7 +108,7 @@ public function denormalize($data, $class, $format = null, array $context = [])
             }
         }
 
-        return $this->objectNormalizer->denormalize($cleanData, $class, $this->format, $context);
+        return $this->objectNormalizer->denormalize($cleanData, $type, $this->format, $context);
     }
 
     /**
diff --git a/src/Denormalizer/PropertiesPropertyDenormalizer.php b/src/Denormalizer/PropertiesPropertyDenormalizer.php
index fc1e088c..9910d712 100644
--- a/src/Denormalizer/PropertiesPropertyDenormalizer.php
+++ b/src/Denormalizer/PropertiesPropertyDenormalizer.php
@@ -41,7 +41,7 @@ public function supportsDenormalization($data, $type, $format = null)
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
         if (is_object($data) && property_exists($data, 'property') && is_array($data->property)) {
             $flatten = [];
@@ -51,6 +51,6 @@ public function denormalize($data, $class, $format = null, array $context = [])
             $data = $flatten;
         }
 
-        return parent::denormalize($data, $class, $format, $context);
+        return parent::denormalize($data, $type, $format, $context);
     }
 }
diff --git a/src/Entity/Property/AppsPropertyAwareTrait.php b/src/Entity/Property/AppsPropertyAwareTrait.php
index 929fa3fe..94991636 100644
--- a/src/Entity/Property/AppsPropertyAwareTrait.php
+++ b/src/Entity/Property/AppsPropertyAwareTrait.php
@@ -30,6 +30,8 @@ trait AppsPropertyAwareTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return string[] Names of apps that this developer owns.
      */
     public function getApps(): array
     {
diff --git a/src/Entity/Property/EnvironmentsPropertyAwareTrait.php b/src/Entity/Property/EnvironmentsPropertyAwareTrait.php
index 8c2cbf26..22eb7103 100644
--- a/src/Entity/Property/EnvironmentsPropertyAwareTrait.php
+++ b/src/Entity/Property/EnvironmentsPropertyAwareTrait.php
@@ -28,6 +28,8 @@ trait EnvironmentsPropertyAwareTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return string[]
      */
     public function getEnvironments(): array
     {
diff --git a/src/Entity/Property/ScopesPropertyAwareTrait.php b/src/Entity/Property/ScopesPropertyAwareTrait.php
index c4ce45ef..3f8b1a28 100644
--- a/src/Entity/Property/ScopesPropertyAwareTrait.php
+++ b/src/Entity/Property/ScopesPropertyAwareTrait.php
@@ -30,6 +30,8 @@ trait ScopesPropertyAwareTrait
 
     /**
      * {@inheritdoc}
+     *
+     * @return string[]
      */
     public function getScopes(): array
     {
diff --git a/src/HttpClient/Plugin/Authentication/ApigeeOnGcpOauth2.php b/src/HttpClient/Plugin/Authentication/ApigeeOnGcpOauth2.php
index 15b57fae..39c7634c 100644
--- a/src/HttpClient/Plugin/Authentication/ApigeeOnGcpOauth2.php
+++ b/src/HttpClient/Plugin/Authentication/ApigeeOnGcpOauth2.php
@@ -116,7 +116,7 @@ protected function getAccessToken(): void
         try {
             $jwt = JWT::encode($token, $this->privateKey, 'RS256');
         } catch (DomainException $e) {
-            throw new ApigeeOnGcpOauth2AuthenticationException($e->getMessage(), $e->getCode(), $e);
+            throw new ApigeeOnGcpOauth2AuthenticationException($e->getMessage(), (int) $e->getCode(), $e);
         }
 
         $body = [
@@ -129,7 +129,7 @@ protected function getAccessToken(): void
             $decodedResponse = json_decode((string) $response->getBody(), true);
             $this->tokenStorage->saveToken($decodedResponse);
         } catch (Exception $e) {
-            throw new ApigeeOnGcpOauth2AuthenticationException($e->getMessage(), $e->getCode(), $e);
+            throw new ApigeeOnGcpOauth2AuthenticationException($e->getMessage(), (int) $e->getCode(), $e);
         }
     }
 }
diff --git a/src/HttpClient/Plugin/Authentication/GceServiceAccount.php b/src/HttpClient/Plugin/Authentication/GceServiceAccount.php
index f23c9044..7a93f8f0 100644
--- a/src/HttpClient/Plugin/Authentication/GceServiceAccount.php
+++ b/src/HttpClient/Plugin/Authentication/GceServiceAccount.php
@@ -86,7 +86,7 @@ protected function getAccessToken(): void
             $decoded_token = json_decode((string) $response->getBody(), true);
             $this->tokenStorage->saveToken($decoded_token);
         } catch (Exception $e) {
-            throw new ApigeeOnGcpOauth2AuthenticationException($e->getMessage(), $e->getCode(), $e);
+            throw new ApigeeOnGcpOauth2AuthenticationException($e->getMessage(), (int) $e->getCode(), $e);
         }
     }
 
diff --git a/src/HttpClient/Plugin/Authentication/HybridOauth2.php b/src/HttpClient/Plugin/Authentication/HybridOauth2.php
index 7e0cc34c..3b54ef10 100644
--- a/src/HttpClient/Plugin/Authentication/HybridOauth2.php
+++ b/src/HttpClient/Plugin/Authentication/HybridOauth2.php
@@ -118,7 +118,7 @@ protected function getAccessToken(): void
         try {
             $jwt = JWT::encode($token, $this->privateKey, 'RS256');
         } catch (DomainException $e) {
-            throw new HybridOauth2AuthenticationException($e->getMessage(), $e->getCode(), $e);
+            throw new HybridOauth2AuthenticationException($e->getMessage(), (int) $e->getCode(), $e);
         }
 
         $body = [
@@ -131,7 +131,7 @@ protected function getAccessToken(): void
             $decodedResponse = json_decode((string) $response->getBody(), true);
             $this->tokenStorage->saveToken($decodedResponse);
         } catch (Exception $e) {
-            throw new HybridOauth2AuthenticationException($e->getMessage(), $e->getCode(), $e);
+            throw new HybridOauth2AuthenticationException($e->getMessage(), (int) $e->getCode(), $e);
         }
     }
 }
diff --git a/src/HttpClient/Plugin/Authentication/Oauth.php b/src/HttpClient/Plugin/Authentication/Oauth.php
index 3a41a8c7..099ed4ce 100644
--- a/src/HttpClient/Plugin/Authentication/Oauth.php
+++ b/src/HttpClient/Plugin/Authentication/Oauth.php
@@ -143,7 +143,7 @@ protected function getAccessToken(): void
             // id and secret.
             $this->getAccessToken();
         } catch (Exception $e) {
-            throw new OauthAuthenticationException($e->getMessage(), $e->getCode(), $e);
+            throw new OauthAuthenticationException($e->getMessage(), (int) $e->getCode(), $e);
         }
     }
 }
diff --git a/src/HttpClient/Plugin/ResponseHandlerPlugin.php b/src/HttpClient/Plugin/ResponseHandlerPlugin.php
index 7209c902..41fcb154 100644
--- a/src/HttpClient/Plugin/ResponseHandlerPlugin.php
+++ b/src/HttpClient/Plugin/ResponseHandlerPlugin.php
@@ -70,10 +70,10 @@ public function handleRequest(RequestInterface $request, callable $next, callabl
             if (is_a($e, HttpException::class)) {
                 $this->decodeResponse($e->getResponse(), $request);
             } elseif (is_a($e, RequestException::class) || is_a($e, NetworkException::class)) {
-                throw new ApiRequestException($request, $e->getMessage(), $e->getCode(), $e);
+                throw new ApiRequestException($request, $e->getMessage(), (int) $e->getCode(), $e);
             }
 
-            throw new ApiException($e->getMessage(), $e->getCode(), $e);
+            throw new ApiException($e->getMessage(), (int) $e->getCode(), $e);
         });
     }
 
diff --git a/src/PropertyAccess/PropertyAccessorDecorator.php b/src/PropertyAccess/PropertyAccessorDecorator.php
index 7593b28e..e8b86ea3 100644
--- a/src/PropertyAccess/PropertyAccessorDecorator.php
+++ b/src/PropertyAccess/PropertyAccessorDecorator.php
@@ -76,7 +76,7 @@ public function setValue(&$objectOrArray, $propertyPath, $value): void
                         $objectOrArray->{$setter}(...$value);
                     }
                 } catch (\TypeError $typeError) {
-                    self::processTypeErrorOnSetValue($typeError->getMessage(), $typeError->getTrace(), 0);
+                    self::processTypeErrorOnSetValue($typeError->getMessage(), $typeError->getTrace(), 0, $typeError);
 
                     // Rethrow the exception if it could not be transformed
                     // to an invalid argument exception.
@@ -174,24 +174,37 @@ private static function processTypeErrorOnGetValue($object, string $property, \T
      * @param $message
      * @param $trace
      * @param $i
+     * @param $previous
      *
      * @see \Symfony\Component\PropertyAccess\PropertyAccessor::throwInvalidArgumentException()
+     *
+     * @psalm-suppress PossiblyFalseOperand
+     * @psalm-suppress PossiblyFalseArgument
      */
-    private static function processTypeErrorOnSetValue($message, $trace, $i): void
+    private static function processTypeErrorOnSetValue($message, $trace, $i, $previous = null): void
     {
-        if (0 !== strpos($message, 'Argument ')) {
+        if (!isset($trace[$i]['file']) || __FILE__ !== $trace[$i]['file']) {
             return;
         }
 
-        if (isset($trace[$i]['file']) && __FILE__ === $trace[$i]['file'] && array_key_exists(0, $trace[$i]['args'])) {
+        if (\PHP_VERSION_ID < 80000) {
+            if (0 !== strpos($message, 'Argument ')) {
+                return;
+            }
+
             $pos = strpos($message, $delim = 'must be of the type ') ?: (strpos($message, $delim = 'must be an instance of ') ?: strpos($message, $delim = 'must implement interface '));
-            if (false !== $pos) {
-                $pos += \strlen($delim);
-                $type = $trace[$i]['args'][0];
-                $type = \is_object($type) ? \get_class($type) : \gettype($type);
+            $pos += \strlen($delim);
+            $j = strpos($message, ',', $pos);
+            $type = substr($message, 2 + $j, strpos($message, ' given', $j) - $j - 2);
+            $message = substr($message, $pos, $j - $pos);
 
-                throw new InvalidArgumentException(sprintf('Expected argument of type "%s", "%s" given.', substr($message, $pos, (int) strpos($message, ',', $pos) - $pos), $type));
-            }
+            throw new InvalidArgumentException(sprintf('Expected argument of type "%s", "%s" given.', $message, 'NULL' === $type ? 'null' : $type), 0, $previous);
+        }
+
+        if (preg_match('/^\S+::\S+\(\): Argument #\d+ \(\$\S+\) must be of type (\S+), (\S+) given/', $message, $matches)) {
+            list(, $expectedType, $actualType) = $matches;
+
+            throw new InvalidArgumentException(sprintf('Expected argument of type "%s", "%s" given.', $expectedType, 'NULL' === $actualType ? 'null' : $actualType), 0, $previous);
         }
     }
 }
diff --git a/src/Serializer/EntitySerializer.php b/src/Serializer/EntitySerializer.php
index 9bece79b..b9643d64 100755
--- a/src/Serializer/EntitySerializer.php
+++ b/src/Serializer/EntitySerializer.php
@@ -71,9 +71,9 @@ public function __construct(array $normalizers = [])
     /**
      * {@inheritdoc}
      */
-    public function denormalize($data, $class, $format = null, array $context = [])
+    public function denormalize($data, $type, $format = null, array $context = [])
     {
-        return $this->serializer->denormalize($data, $class, $format, $context);
+        return $this->serializer->denormalize($data, $type, $format, $context);
     }
 
     /**
diff --git a/tests/PropertyAccess/PropertyAccessorDecoratorTest.php b/tests/PropertyAccess/PropertyAccessorDecoratorTest.php
index e4da1aaf..3e61eb12 100644
--- a/tests/PropertyAccess/PropertyAccessorDecoratorTest.php
+++ b/tests/PropertyAccess/PropertyAccessorDecoratorTest.php
@@ -189,7 +189,7 @@ public function exceptionsToGetOnGetValue(): array
     public function exceptionsToGetOnSetValue(): array
     {
         return [
-            ['shouldBeAStringArray', [null], InvalidArgumentException::class, '/^Expected argument of type "string", "NULL" given/'],
+            ['shouldBeAStringArray', [null], InvalidArgumentException::class, '/^Expected argument of type "string", "null" given/'],
         ];
     }
 }
diff --git a/tests/Serializer/EntitySerializerTest.php b/tests/Serializer/EntitySerializerTest.php
index b2b4920b..25ae48d7 100644
--- a/tests/Serializer/EntitySerializerTest.php
+++ b/tests/Serializer/EntitySerializerTest.php
@@ -181,7 +181,7 @@ public function testSetPropertiesFromResponseWithValidValues(): void
 
     /**
      * @expectedException \Symfony\Component\Serializer\Exception\NotNormalizableValueException
-     * @expectedExceptionMessage Expected argument of type "string", "stdClass" given.
+     * @expectedExceptionMessage Expected argument of type "string", "object" given.
      */
     public function testSetPropertiesFromResponseWithInvalidValue(): void
     {
diff --git a/tests/Test/TestClientFactory.php b/tests/Test/TestClientFactory.php
index 570ac627..fe99bef7 100644
--- a/tests/Test/TestClientFactory.php
+++ b/tests/Test/TestClientFactory.php
@@ -47,7 +47,7 @@ private function __clone()
     {
     }
 
-    private function __wakeup(): void
+    public function __wakeup(): void
     {
     }