001/*
002  GRANITE DATA SERVICES
003  Copyright (C) 2011 GRANITE DATA SERVICES S.A.S.
004
005  This file is part of Granite Data Services.
006
007  Granite Data Services is free software; you can redistribute it and/or modify
008  it under the terms of the GNU Library General Public License as published by
009  the Free Software Foundation; either version 2 of the License, or (at your
010  option) any later version.
011
012  Granite Data Services is distributed in the hope that it will be useful, but
013  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
014  FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License
015  for more details.
016
017  You should have received a copy of the GNU Library General Public License
018  along with this library; if not, see <http://www.gnu.org/licenses/>.
019*/
020
021package org.granite.messaging.amf.io.util.instantiator;
022
023import java.util.ArrayList;
024import java.util.Collections;
025import java.util.List;
026
027import org.granite.messaging.service.ServiceException;
028import org.granite.util.TypeUtil;
029
030/**
031 * @author Igor SAZHNEV
032 */
033public class EnumInstantiator extends AbstractInstantiator<Enum<?>> {
034
035    private static final long serialVersionUID = -6116814787518316453L;
036
037    private final String type;
038
039    private static final List<String> orderedFields;
040    static {
041        List<String> of = new ArrayList<String>(1);
042        of.add("value");
043        orderedFields = Collections.unmodifiableList(of);
044    }
045
046    public EnumInstantiator(String type) {
047        this.type = type;
048    }
049
050    @Override
051    public List<String> getOrderedFieldNames() {
052        return orderedFields;
053    }
054
055    @SuppressWarnings({ "unchecked", "rawtypes" })
056    @Override
057    public Enum<?> newInstance() {
058        Enum<?> enumInstance = null;
059
060        String enumValue = null;
061        try {
062            Class<? extends Enum> enumClass = (Class<? extends Enum>)TypeUtil.forName(type);
063            enumValue = (String)get("value");
064            if (enumValue == null) {
065                Object[] enumConstants = enumClass.getEnumConstants();
066                if (enumConstants == null || enumConstants.length == 0)
067                    throw new ServiceException("Invalid Enum type: " + type);
068                enumValue = ((Enum<?>)enumConstants[0]).name();
069            }
070            enumInstance = Enum.valueOf(enumClass, enumValue);
071        } catch (ClassNotFoundException e) {
072            throw new ServiceException("Could not find Enum type for: " + type, e);
073        } catch (IllegalArgumentException e) {
074            throw new ServiceException("Could not find Enum constant for: " + type + '.' + enumValue, e);
075        }
076
077        return enumInstance;
078    }
079}