001/* Copyright (C) 2013 TU Dortmund
002 * This file is part of AutomataLib, http://www.automatalib.net/.
003 * 
004 * AutomataLib is free software; you can redistribute it and/or
005 * modify it under the terms of the GNU Lesser General Public
006 * License version 3.0 as published by the Free Software Foundation.
007 * 
008 * AutomataLib is distributed in the hope that it will be useful,
009 * but WITHOUT ANY WARRANTY; without even the implied warranty of
010 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
011 * Lesser General Public License for more details.
012 * 
013 * You should have received a copy of the GNU Lesser General Public
014 * License along with AutomataLib; if not, see
015 * http://www.gnu.de/documents/lgpl.en.html.
016 */
017package net.automatalib.automata.base;
018
019import net.automatalib.automata.Automaton;
020import net.automatalib.automata.concepts.StateIDs;
021import net.automatalib.commons.util.array.ResizingObjectArray;
022import net.automatalib.commons.util.mappings.MutableMapping;
023
024public class StateIDGrowingMapping<S,V> implements MutableMapping<S,V> {
025
026        private final Automaton<S,?,?> automaton;
027        private final StateIDs<S> stateIds;
028        private final ResizingObjectArray storage;
029        
030        public StateIDGrowingMapping(Automaton<S,?,?> automaton, StateIDs<S> stateIds) {
031                this.automaton = automaton;
032                this.stateIds = stateIds;
033                this.storage = new ResizingObjectArray(automaton.size());
034        }
035
036        /*
037         * (non-Javadoc)
038         * @see net.automatalib.commons.util.mappings.Mapping#get(java.lang.Object)
039         */
040        @Override
041        @SuppressWarnings("unchecked")
042        public V get(S elem) {
043                int id = stateIds.getStateId(elem);
044                if(id < storage.array.length)
045                        return (V)storage.array[id];
046                return null;
047        }
048
049        /*
050         * (non-Javadoc)
051         * @see net.automatalib.commons.util.mappings.MutableMapping#put(java.lang.Object, java.lang.Object)
052         */
053        @Override
054        @SuppressWarnings("unchecked")
055        public V put(S key, V value) {
056                int id = stateIds.getStateId(key);
057                if(id >= storage.array.length)
058                        storage.ensureCapacity(automaton.size());
059                V old = (V)storage.array[id];
060                storage.array[id] = value;
061                return old;
062        }
063
064}