/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.isis.core.metamodel.interactions;
import org.apache.isis.applib.events.ValidityEvent;
import org.apache.isis.core.metamodel.facetapi.Facet;
import org.apache.isis.core.metamodel.facetapi.FacetAbstract.Validating;
/**
* Mix-in interface for {@link Facet}s that can advise as to whether a proposed
* value is valid.
*
* <p>
* For example, <tt>MaxLengthFacet</tt> does constrain the length of candidate
* values, whereas <tt>DebugFacet</tt> or <tt>MemberOrderFacet</tt> do not -
* they are basically just UI hints.
*
* @see DisablingInteractionAdvisor
* @see HidingInteractionAdvisor
*/
public interface ValidatingInteractionAdvisor extends InteractionAdvisorFacet, Validating {
/**
* Whether the validation represented by this facet passes or fails.
*
* <p>
* Implementations should use the provided {@link ValidityContext} to
* determine whether they declare the interaction invalid. They must however
* guard against a <tt>null</tt> {@link ValidityContext#getTarget() target}
* and {@link ValidityContext#getSession() session} - neither are guaranteed
* to be populated.
*/
String invalidates(final ValidityContext<? extends ValidityEvent> ic);
}