64 files declare their use of Cache

AccessResult.php in core/lib/Drupal/Core/Access/AccessResult.php
AccessResultTest.php in core/tests/Drupal/Tests/Core/Access/AccessResultTest.php
AnnounceTestHttpClientMiddleware.php in core/modules/announcements_feed/tests/modules/announce_feed_test/src/AnnounceTestHttpClientMiddleware.php
BackendChainImplementationUnitTest.php in core/tests/Drupal/Tests/Core/Cache/BackendChainImplementationUnitTest.php
BreadcrumbManagerTest.php in core/tests/Drupal/Tests/Core/Breadcrumb/BreadcrumbManagerTest.php
BubbleableMetadataTest.php in core/tests/Drupal/Tests/Core/Render/BubbleableMetadataTest.php
CacheableMetadataTest.php in core/tests/Drupal/Tests/Core/Cache/CacheableMetadataTest.php
CacheBackendDecorator.php in core/modules/system/tests/modules/performance_test/src/Cache/CacheBackendDecorator.php
CacheCollectorTest.php in core/tests/Drupal/Tests/Core/Cache/CacheCollectorTest.php
CacheRouterRebuildSubscriber.php in core/lib/Drupal/Core/EventSubscriber/CacheRouterRebuildSubscriber.php
CacheTest.php in core/tests/Drupal/Tests/Core/Cache/CacheTest.php
common.inc in core/includes/common.inc
Common functions that many Drupal modules will need to reference.
Config.php in core/lib/Drupal/Core/Config/Config.php
ConfigBase.php in core/lib/Drupal/Core/Config/ConfigBase.php
ConfigEntityBase.php in core/lib/Drupal/Core/Config/Entity/ConfigEntityBase.php
ConfigEntityStorageTest.php in core/tests/Drupal/Tests/Core/Config/Entity/ConfigEntityStorageTest.php
ConfigFactory.php in core/lib/Drupal/Core/Config/ConfigFactory.php
ContentEntityStorageBase.php in core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
ContextAwarePluginTrait.php in core/lib/Drupal/Core/Plugin/ContextAwarePluginTrait.php
DefaultPluginManager.php in core/lib/Drupal/Core/Plugin/DefaultPluginManager.php
EntityBase.php in core/lib/Drupal/Core/Entity/EntityBase.php
EntityComputedFieldTest.php in core/modules/system/tests/src/Functional/Entity/EntityComputedFieldTest.php
EntityFieldManager.php in core/lib/Drupal/Core/Entity/EntityFieldManager.php
EntityFieldManagerTest.php in core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
EntityLastInstalledSchemaRepository.php in core/lib/Drupal/Core/Entity/EntityLastInstalledSchemaRepository.php
EntityTypeBundleInfo.php in core/lib/Drupal/Core/Entity/EntityTypeBundleInfo.php
EntityTypeBundleInfoTest.php in core/tests/Drupal/Tests/Core/Entity/EntityTypeBundleInfoTest.php
EntityUnitTest.php in core/tests/Drupal/Tests/Core/Entity/EntityUnitTest.php
EntityViewBuilder.php in core/lib/Drupal/Core/Entity/EntityViewBuilder.php
HelpTopicTwig.php in core/modules/help/src/HelpTopicTwig.php
HelpTopicTwigTest.php in core/modules/help/tests/src/Unit/HelpTopicTwigTest.php
HtmlRenderer.php in core/lib/Drupal/Core/Render/MainContent/HtmlRenderer.php
LibraryDiscoveryCollectorTest.php in core/tests/Drupal/Tests/Core/Asset/LibraryDiscoveryCollectorTest.php
LocalActionDefault.php in core/lib/Drupal/Core/Menu/LocalActionDefault.php
LocalTaskDefault.php in core/lib/Drupal/Core/Menu/LocalTaskDefault.php
LocalTaskManager.php in core/lib/Drupal/Core/Menu/LocalTaskManager.php
LocalTaskManagerTest.php in core/tests/Drupal/Tests/Core/Menu/LocalTaskManagerTest.php
MenuLinkBase.php in core/lib/Drupal/Core/Menu/MenuLinkBase.php
MenuLinkMock.php in core/tests/Drupal/Tests/Core/Menu/MenuLinkMock.php
MenuRouterRebuildSubscriber.php in core/lib/Drupal/Core/EventSubscriber/MenuRouterRebuildSubscriber.php
MenuTreeStorage.php in core/lib/Drupal/Core/Menu/MenuTreeStorage.php
ModuleInstaller.php in core/lib/Drupal/Core/Extension/ModuleInstaller.php
OpenTelemetryFrontPagePerformanceTest.php in core/profiles/demo_umami/tests/src/FunctionalJavascript/OpenTelemetryFrontPagePerformanceTest.php
OpenTelemetryNodePagePerformanceTest.php in core/profiles/demo_umami/tests/src/FunctionalJavascript/OpenTelemetryNodePagePerformanceTest.php
PermissionsHashGenerator.php in core/lib/Drupal/Core/Session/PermissionsHashGenerator.php
PermissionsHashGeneratorTest.php in core/tests/Drupal/Tests/Core/Session/PermissionsHashGeneratorTest.php
PlaceholderGenerator.php in core/lib/Drupal/Core/Render/PlaceholderGenerator.php
PlaceholderGeneratorTest.php in core/tests/Drupal/Tests/Core/Render/PlaceholderGeneratorTest.php
RefreshVariablesTrait.php in core/lib/Drupal/Core/Test/RefreshVariablesTrait.php
Registry.php in core/lib/Drupal/Core/Theme/Registry.php
Renderer.php in core/lib/Drupal/Core/Render/Renderer.php
RendererBubblingTest.php in core/tests/Drupal/Tests/Core/Render/RendererBubblingTest.php
RendererPlaceholdersTest.php in core/tests/Drupal/Tests/Core/Render/RendererPlaceholdersTest.php
RendererTest.php in core/tests/Drupal/Tests/Core/Render/RendererTest.php
RendererTestBase.php in core/tests/Drupal/Tests/Core/Render/RendererTestBase.php
RouteProcessorManagerTest.php in core/tests/Drupal/Tests/Core/RouteProcessor/RouteProcessorManagerTest.php
RouteProvider.php in core/lib/Drupal/Core/Routing/RouteProvider.php
StandardPerformanceTest.php in core/profiles/standard/tests/src/FunctionalJavascript/StandardPerformanceTest.php
StyleSerializerEntityTest.php in core/modules/rest/tests/src/Functional/Views/StyleSerializerEntityTest.php
SuperUserAccessPolicyTest.php in core/tests/Drupal/Tests/Core/Session/SuperUserAccessPolicyTest.php
TestHelpTopicPlugin.php in core/modules/help/tests/modules/help_topics_test/src/Plugin/HelpTopic/TestHelpTopicPlugin.php
ThemeRegistry.php in core/lib/Drupal/Core/Utility/ThemeRegistry.php
UrlGeneratorTest.php in core/tests/Drupal/Tests/Core/Routing/UrlGeneratorTest.php
UserRolesAccessPolicyTest.php in core/tests/Drupal/Tests/Core/Session/UserRolesAccessPolicyTest.php

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