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 */ 020 021 package org.apache.directory.shared.dsmlv2; 022 023 024 /** 025 * Define a transition between two states of a grammar. It stores the next 026 * state, and the action to execute while transiting. 027 * 028 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 029 * @version $Rev$, $Date$ 030 */ 031 public class GrammarTransition 032 { 033 /** The next state in the grammar */ 034 private int nextState; 035 036 /** The action associated to the transition */ 037 private GrammarAction action; 038 039 /** The current state */ 040 private int currentState; 041 042 043 /** 044 * Creates a new GrammarTransition object. 045 * 046 * @param currentState 047 * The current transition 048 * @param nextState 049 * The target state 050 * @param action 051 * The action to execute. It could be null. 052 */ 053 public GrammarTransition( int currentState, int nextState, GrammarAction action ) 054 { 055 this.currentState = currentState; 056 this.nextState = nextState; 057 this.action = action; 058 } 059 060 /** 061 * Gets the target state 062 * 063 * @return 064 * the target state. 065 */ 066 public int getNextState() 067 { 068 return nextState; 069 } 070 071 072 /** 073 * Tells if the transition has an associated action. 074 * 075 * @return 076 * <code>true</code> if an action has been asociated to the 077 * transition 078 */ 079 public boolean hasAction() 080 { 081 return action != null; 082 } 083 084 085 /** 086 * Gets the action associated with the transition 087 * 088 * @return 089 * the action associated with the transition 090 */ 091 public GrammarAction getAction() 092 { 093 return action; 094 } 095 096 097 /** 098 * Returns a representation of the transition as a string 099 * 100 * @param grammar 101 * the grammar which state we want a String from 102 * @param statesEnum 103 * the states enum that contains the states' names 104 * @return 105 * a representation of the transition as a string. 106 */ 107 public String toString( int grammar, IStates statesEnum ) 108 { 109 110 StringBuffer sb = new StringBuffer(); 111 112 sb.append( "Transition from <" ).append( statesEnum.getState( currentState ) ).append( "> to <" ).append( 113 statesEnum.getState( nextState ) ).append( ">, action : " ).append( 114 ( ( action == null ) ? "no action" : action.toString() ) ).append( ">" ); 115 116 return sb.toString(); 117 } 118 }