60 classes are annotated with Constraint

AllowedValuesConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/AllowedValuesConstraint.php
Checks for the value being allowed.
BlockContentEntityChangedConstraint in core/modules/block_content/src/Plugin/Validation/Constraint/BlockContentEntityChangedConstraint.php
Validation constraint for the block content entity changed timestamp.
BookOutlineConstraint in core/modules/book/src/Plugin/Validation/Constraint/BookOutlineConstraint.php
Validation constraint for changing the book outline in pending revisions.
BundleConstraint in core/lib/Drupal/Core/Entity/Plugin/Validation/Constraint/BundleConstraint.php
Checks if a value is a valid entity type.
CKEditor5ElementConstraint in core/modules/ckeditor5/src/Plugin/Validation/Constraint/CKEditor5ElementConstraint.php
CKEditor 5 element.
CommentNameConstraint in core/modules/comment/src/Plugin/Validation/Constraint/CommentNameConstraint.php
Supports validating comment author names.
ComplexDataConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ComplexDataConstraint.php
Complex data constraint.
ContentTranslationSynchronizedFieldsConstraint in core/modules/content_translation/src/Plugin/Validation/Constraint/ContentTranslationSynchronizedFieldsConstraint.php
Validation constraint for the entity changed timestamp.
CountConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/CountConstraint.php
Count constraint.
DateTimeFormatConstraint in core/modules/datetime/src/Plugin/Validation/Constraint/DateTimeFormatConstraint.php
Validation constraint for DateTime items to ensure the format is correct.
DeletedWorkspaceConstraint in core/modules/workspaces/src/Plugin/Validation/Constraint/DeletedWorkspaceConstraint.php
Deleted workspace constraint.
EmailConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/EmailConstraint.php
Count constraint.
EntityChangedConstraint in core/lib/Drupal/Core/Entity/Plugin/Validation/Constraint/EntityChangedConstraint.php
Validation constraint for the entity changed timestamp.
EntityHasFieldConstraint in core/lib/Drupal/Core/Entity/Plugin/Validation/Constraint/EntityHasFieldConstraint.php
Checks if a value is an entity that has a specific field.
EntityReferenceSupportedNewEntitiesConstraint in core/modules/workspaces/src/Plugin/Validation/Constraint/EntityReferenceSupportedNewEntitiesConstraint.php
The entity reference supported new entities constraint.
EntityTestCompositeConstraint in core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestCompositeConstraint.php
Constraint with multiple fields.
EntityTestContainerFactoryPlugin in core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestContainerFactoryPlugin.php
A dummy constraint for testing \Drupal\Core\Validation\ConstraintFactory.
EntityTestDefaultPlugin in core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestDefaultPlugin.php
A dummy constraint for testing \Drupal\Core\Validation\ConstraintFactory.
EntityTestEntityLevel in core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/EntityTestEntityLevel.php
Constraint on entity level.
EntityTypeConstraint in core/lib/Drupal/Core/Entity/Plugin/Validation/Constraint/EntityTypeConstraint.php
Checks if a value is a valid entity type.
EntityUntranslatableFieldsConstraint in core/lib/Drupal/Core/Entity/Plugin/Validation/Constraint/EntityUntranslatableFieldsConstraint.php
Validation constraint for the entity changed timestamp.
EntityWorkspaceConflictConstraint in core/modules/workspaces/src/Plugin/Validation/Constraint/EntityWorkspaceConflictConstraint.php
Validation constraint for an entity being edited in multiple workspaces.
FeedTitleConstraint in core/modules/aggregator/src/Plugin/Validation/Constraint/FeedTitleConstraint.php
Supports validating feed titles.
FeedUrlConstraint in core/modules/aggregator/src/Plugin/Validation/Constraint/FeedUrlConstraint.php
Supports validating feed URLs.
FieldWidgetConstraint in core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/FieldWidgetConstraint.php
Supports validating widget constraints.
FileUriUnique in core/modules/file/src/Plugin/Validation/Constraint/FileUriUnique.php
Supports validating file URIs.
FileValidationConstraint in core/modules/file/src/Plugin/Validation/Constraint/FileValidationConstraint.php
Validation File constraint.
ForumLeafConstraint in core/modules/forum/src/Plugin/Validation/Constraint/ForumLeafConstraint.php
Checks that the node is assigned only a "leaf" term in the forum taxonomy.
IsNullConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/IsNullConstraint.php
Null constraint.
LengthConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/LengthConstraint.php
Length constraint.
LinkAccessConstraint in core/modules/link/src/Plugin/Validation/Constraint/LinkAccessConstraint.php
Defines an access validation constraint for links.
LinkExternalProtocolsConstraint in core/modules/link/src/Plugin/Validation/Constraint/LinkExternalProtocolsConstraint.php
Defines a protocol validation constraint for links to external URLs.
LinkNotExistingInternalConstraint in core/modules/link/src/Plugin/Validation/Constraint/LinkNotExistingInternalConstraint.php
Defines a protocol validation constraint for links to broken internal URLs.
LinkTypeConstraint in core/modules/link/src/Plugin/Validation/Constraint/LinkTypeConstraint.php
Validation constraint for links receiving data allowed by its settings.
MediaTestConstraint in core/modules/media/tests/modules/media_test_source/src/Plugin/Validation/Constraint/MediaTestConstraint.php
A media test constraint.
MenuSettingsConstraint in core/modules/menu_ui/src/Plugin/Validation/Constraint/MenuSettingsConstraint.php
Validation constraint for changing the menu settings in pending revisions.
MenuTreeHierarchyConstraint in core/modules/menu_link_content/src/Plugin/Validation/Constraint/MenuTreeHierarchyConstraint.php
Validation constraint for changing the menu hierarchy in pending revisions.
ModerationStateConstraint in core/modules/content_moderation/src/Plugin/Validation/Constraint/ModerationStateConstraint.php
Verifies that nodes have a valid moderation state.
NotNullConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/NotNullConstraint.php
NotNull constraint.
OEmbedResourceConstraint in core/modules/media/src/Plugin/Validation/Constraint/OEmbedResourceConstraint.php
Checks if a value represents a valid oEmbed resource URL.
PathAliasConstraint in core/modules/path/src/Plugin/Validation/Constraint/PathAliasConstraint.php
Validation constraint for changing path aliases in pending revisions.
PrimitiveTypeConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/PrimitiveTypeConstraint.php
Supports validating all primitive types.
ProtectedUserFieldConstraint in core/modules/user/src/Plugin/Validation/Constraint/ProtectedUserFieldConstraint.php
Checks if the plain text password is provided for editing a protected field.
RangeConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/RangeConstraint.php
Range constraint.
ReferenceAccessConstraint in core/lib/Drupal/Core/Entity/Plugin/Validation/Constraint/ReferenceAccessConstraint.php
Entity Reference valid reference constraint.
RegexConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/RegexConstraint.php
Regex constraint.
RestTestConstraint in core/modules/rest/tests/modules/rest_test/src/Plugin/Validation/Constraint/RestTestConstraint.php
Adds some validations for a REST test field.
TaxonomyTermHierarchyConstraint in core/modules/taxonomy/src/Plugin/Validation/Constraint/TaxonomyTermHierarchyConstraint.php
Validation constraint for changing the term hierarchy in pending revisions.
TestFieldConstraint in core/modules/field/tests/modules/field_test/src/Plugin/Validation/Constraint/TestFieldConstraint.php
Checks if a value is not equal.
TestValidatedReferenceConstraint in core/modules/system/tests/modules/entity_test/src/Plugin/Validation/Constraint/TestValidatedReferenceConstraint.php
Validates referenced entities.
ToolbarItemConstraint in core/modules/ckeditor5/src/Plugin/Validation/Constraint/ToolbarItemConstraint.php
A CKEditor 5 toolbar item.
UniqueFieldConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/UniqueFieldConstraint.php
Checks if an entity field has a unique value.
UniquePathAliasConstraint in core/lib/Drupal/Core/Path/Plugin/Validation/Constraint/UniquePathAliasConstraint.php
Validation constraint for unique path alias values.
UserMailRequired in core/modules/user/src/Plugin/Validation/Constraint/UserMailRequired.php
Checks if the user's email address is provided if required.
UserMailUnique in core/modules/user/src/Plugin/Validation/Constraint/UserMailUnique.php
Checks if a user's email address is unique on the site.
UserNameConstraint in core/modules/user/src/Plugin/Validation/Constraint/UserNameConstraint.php
Checks if a value is a valid user name.
UserNameUnique in core/modules/user/src/Plugin/Validation/Constraint/UserNameUnique.php
Checks if a user name is unique on the site.
UuidConstraint in core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/UuidConstraint.php
Validates a UUID.
ValidPathConstraint in core/lib/Drupal/Core/Path/Plugin/Validation/Constraint/ValidPathConstraint.php
Validation constraint for valid system paths.
ValidReferenceConstraint in core/lib/Drupal/Core/Entity/Plugin/Validation/Constraint/ValidReferenceConstraint.php
Entity Reference valid reference constraint.

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