MetadataInterface deprecated

A container for validation metadata.

The container contains constraints that may belong to different validation groups. Constraints for a specific group can be fetched by calling {@link findConstraints}.

Implement this interface to add validation metadata to your own metadata layer. Each metadata may have named properties. Each property can be represented by one or more {@link PropertyMetadataInterface} instances that are returned by {@link getPropertyMetadata}. Since PropertyMetadataInterface inherits from MetadataInterface, each property may be divided into further properties.

The {@link accept} method of each metadata implements the Visitor pattern. The method should forward the call to the visitor's {@link ValidationVisitorInterface::visit} method and additionally call accept() on all structurally related metadata instances.

For example, to store constraints for PHP classes and their properties, create a class ClassMetadata (implementing MetadataInterface) and a class PropertyMetadata (implementing PropertyMetadataInterface). ClassMetadata::getPropertyMetadata($property) returns all PropertyMetadata instances for a property of that class. Its accept()-method simply forwards to ValidationVisitorInterface::visit() and calls accept() on all contained PropertyMetadata instances, which themselves call ValidationVisitorInterface::visit() again.