--- /dev/null
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Validator;
+
+/**
+ * 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
+ * <tt>PropertyMetadataInterface</tt> inherits from <tt>MetadataInterface</tt>,
+ * 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
+ * <tt>accept()</tt> on all structurally related metadata instances.
+ *
+ * For example, to store constraints for PHP classes and their properties,
+ * create a class <tt>ClassMetadata</tt> (implementing <tt>MetadataInterface</tt>)
+ * and a class <tt>PropertyMetadata</tt> (implementing <tt>PropertyMetadataInterface</tt>).
+ * <tt>ClassMetadata::getPropertyMetadata($property)</tt> returns all
+ * <tt>PropertyMetadata</tt> instances for a property of that class. Its
+ * <tt>accept()</tt>-method simply forwards to <tt>ValidationVisitorInterface::visit()</tt>
+ * and calls <tt>accept()</tt> on all contained <tt>PropertyMetadata</tt>
+ * instances, which themselves call <tt>ValidationVisitorInterface::visit()</tt>
+ * again.
+ *
+ * @author Bernhard Schussek <bschussek@gmail.com>
+ *
+ * @deprecated since version 2.5, to be removed in 3.0.
+ * Use {@link Mapping\MetadataInterface} instead.
+ */
+interface MetadataInterface
+{
+ /**
+ * Implementation of the Visitor design pattern.
+ *
+ * Calls {@link ValidationVisitorInterface::visit} and then forwards the
+ * <tt>accept()</tt>-call to all property metadata instances.
+ *
+ * @param ValidationVisitorInterface $visitor The visitor implementing the validation logic
+ * @param mixed $value The value to validate
+ * @param string|string[] $group The validation group to validate in
+ * @param string $propertyPath The current property path in the validation graph
+ *
+ * @deprecated since version 2.5, to be removed in 3.0.
+ */
+ public function accept(ValidationVisitorInterface $visitor, $value, $group, $propertyPath);
+
+ /**
+ * Returns all constraints for a given validation group.
+ *
+ * @param string $group The validation group
+ *
+ * @return Constraint[] A list of constraint instances
+ */
+ public function findConstraints($group);
+}