001/*
002 *  Licensed to the Apache Software Foundation (ASF) under one
003 *  or more contributor license agreements.  See the NOTICE file
004 *  distributed with this work for additional information
005 *  regarding copyright ownership.  The ASF licenses this file
006 *  to you under the Apache License, Version 2.0 (the
007 *  "License"); you may not use this file except in compliance
008 *  with the License.  You may obtain a copy of the License at
009 *
010 *        http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *  Unless required by applicable law or agreed to in writing,
013 *  software distributed under the License is distributed on an
014 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 *  KIND, either express or implied.  See the License for the
016 *  specific language governing permissions and limitations
017 *  under the License.
018 */
019
020package org.apache.isis.core.metamodel.facets.maxlen;
021
022import org.apache.isis.applib.events.ValidityEvent;
023import org.apache.isis.core.metamodel.adapter.ObjectAdapter;
024import org.apache.isis.core.metamodel.facetapi.Facet;
025import org.apache.isis.core.metamodel.facetapi.FacetHolder;
026import org.apache.isis.core.metamodel.facets.SingleIntValueFacetAbstract;
027import org.apache.isis.core.metamodel.interactions.ProposedHolder;
028import org.apache.isis.core.metamodel.interactions.ValidityContext;
029import org.apache.isis.core.metamodel.spec.ObjectAdapterUtils;
030
031public abstract class MaxLengthFacetAbstract extends SingleIntValueFacetAbstract implements MaxLengthFacet {
032
033    public static Class<? extends Facet> type() {
034        return MaxLengthFacet.class;
035    }
036
037    public MaxLengthFacetAbstract(final int value, final FacetHolder holder) {
038        super(type(), holder, value);
039    }
040
041    /**
042     * Whether the provided argument exceeds the {@link #value() maximum length}
043     * .
044     */
045    @Override
046    public boolean exceeds(final ObjectAdapter adapter) {
047        final String str = ObjectAdapterUtils.unwrapObjectAsString(adapter);
048        if (str == null) {
049            return false;
050        }
051        final int maxLength = value();
052        return maxLength != 0 && str.length() > maxLength;
053    }
054
055    @Override
056    public String invalidates(final ValidityContext<? extends ValidityEvent> context) {
057        if (!(context instanceof ProposedHolder)) {
058            return null;
059        }
060        final ProposedHolder proposedHolder = (ProposedHolder) context;
061        final ObjectAdapter proposedArgument = proposedHolder.getProposed();
062        if (!exceeds(proposedArgument)) {
063            return null;
064        }
065        return "The value proposed exceeds the maximum length of " + value();
066    }
067
068    @Override
069    protected String toStringValues() {
070        final int val = value();
071        return val == 0 ? "unlimited" : String.valueOf(val);
072    }
073
074}