/*
* 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.facets.objectvalue.mandatory;
import org.apache.isis.core.metamodel.adapter.ObjectAdapter;
import org.apache.isis.core.metamodel.facetapi.Facet;
import org.apache.isis.core.metamodel.facetapi.FacetHolder;
import org.apache.isis.core.metamodel.facets.MarkerFacet;
import org.apache.isis.core.metamodel.interactions.ValidatingInteractionAdvisor;
/**
* Whether a property or a parameter is mandatory (not optional).
*
* <p>
* For a mandatory property, the object cannot be saved/updated without the
* value being provided. For a mandatory parameter, the action cannot be invoked
* without the value being provided.
*
* <p>
* In the standard Apache Isis Programming Model, specify mandatory by
* <i>omitting</i> the <tt>@Optional</tt> annotation.
*/
public interface MandatoryFacet extends MarkerFacet, ValidatingInteractionAdvisor {
/**
* Whether this value is required but has not been provided (and is
* therefore invalid).
*
* <p>
* If the value has been provided, <i>or</i> if the property or parameter is
* not required, then will return <tt>false</tt>.
*/
boolean isRequiredButNull(ObjectAdapter adapter);
/**
* Indicates that the implementation is overridding the usual semantics, in
* other words that the {@link FacetHolder} to which this {@link Facet} is
* attached is <i>not</i> mandatory.
*/
public boolean isInvertedSemantics();
}