001/*
002 * Licensed to DuraSpace under one or more contributor license agreements.
003 * See the NOTICE file distributed with this work for additional information
004 * regarding copyright ownership.
005 *
006 * DuraSpace licenses this file to you under the Apache License,
007 * Version 2.0 (the "License"); you may not use this file except in
008 * compliance 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, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.fcrepo.kernel.api.models;
019
020import org.fcrepo.kernel.api.Transaction;
021import org.fcrepo.kernel.api.identifiers.FedoraId;
022
023/**
024 * Utility class interface for helper methods.
025 * @author whikloj
026 * @since 6.0.0
027 */
028public interface ResourceHelper {
029
030    /**
031     * Check if a resource exists.
032     * @param transaction The current transaction
033     * @param fedoraId The internal identifier
034     * @param includeDeleted Whether to check for deleted resources too.
035     * @return True if the identifier resolves to a resource.
036     */
037    public boolean doesResourceExist(final Transaction transaction, final FedoraId fedoraId,
038                                     final boolean includeDeleted);
039
040    /**
041     * Is the resource a "ghost node". Ghost nodes are defined as a resource that does not exist, but whose URI is part
042     * of the URI of another resource? For example:
043     *
044     * http://localhost/rest/a/b - does exist
045     * http://localhost/rest/a - does not exist and is therefore a ghost node.
046     *
047     * @param transaction The transaction
048     * @param resourceId Identifier of the resource
049     * @return Whether the resource does not exist, but has
050     */
051    public boolean isGhostNode(final Transaction transaction, final FedoraId resourceId);
052}