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.services; 019 020import org.fcrepo.kernel.api.FedoraSession; 021 022/** 023 * @author bbpennel 024 * @author barmintor 025 * @since Feb 21, 2014 026 */ 027public interface Service<T> { 028 /** 029 * Test whether T exists at the given path in the 030 * repository 031 * 032 * @param path the path 033 * @param session the session 034 * @return whether T exists at the given path 035 */ 036 boolean exists(final FedoraSession session, final String path); 037 /** 038 * Retrieve an existing T instance by session and path 039 * 040 * @param path the path to the node 041 * @param session the session 042 * @return retrieved T 043 */ 044 T find(final FedoraSession session, final String path); 045 /** 046 * Retrieve a T instance by session and path 047 * 048 * @param session the session 049 * @param path the path to the node 050 * @return retrieved T 051 */ 052 T findOrCreate(final FedoraSession session, final String path); 053}