1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 */ 19 package org.apache.directory.server.core.cursor; 20 21 22 /** 23 * A Cursor's state: cursor states leverage the State Pattern to isolate state 24 * specific transition logic with certain operations. Not every Cursor is 25 * that complex so the implementor should decide whether or not using the 26 * State Pattern is over kill on a per Cursor implementation basis. 27 * 28 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 29 * @version $Rev$, $Date$ 30 */ 31 public interface CursorState<E> 32 { 33 void before( E element ) throws Exception; 34 35 void after( E element ) throws Exception; 36 37 void beforeFirst() throws Exception; 38 39 void afterLast() throws Exception; 40 41 boolean first() throws Exception; 42 43 boolean last() throws Exception; 44 45 boolean previous() throws Exception; 46 47 boolean next() throws Exception; 48 }