    001// Copyright 2007, 2008 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007//     http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.util;
    016
    017import java.io.Serializable;
    018import java.util.List;
    019
    020import org.apache.tapestry5.OptionGroupModel;
    021import org.apache.tapestry5.OptionModel;
    022import org.apache.tapestry5.commons.Messages;
    023import org.apache.tapestry5.commons.util.CollectionFactory;
    024import org.apache.tapestry5.internal.OptionModelImpl;
    025import org.apache.tapestry5.internal.TapestryInternalUtils;
    026
    027/**
    028 * A basic select model for a particular Enum type. The labels for each Enum are drawn from the Enum instance name and
    029 * the provided message catalog: <ul> <li>As key <em>ClassName</em>.<em>name</em> if present. The class name excludes
    030 * the package portion. Ex: "ElementType.LOCAL_VARIABLE" <li>As key <em>name</em> if present, i.e., "LOCAL_VARIABLE".
    031 * <li>As a user-presentable version of the name, i.e., "Local Variable". </ul>
    032 */
    033public final class EnumSelectModel extends AbstractSelectModel implements Serializable
    034{
    035    private static final long serialVersionUID = -3590412082766899684L;
    036
    037    private final List<OptionModel> options = CollectionFactory.newList();
    038
    039    public <T extends Enum> EnumSelectModel(Class<T> enumClass, Messages messages)
    040    {
    041        this(enumClass, messages, enumClass.getEnumConstants());
    042    }
    043
    044    public <T extends Enum> EnumSelectModel(Class<T> enumClass, Messages messages, T[] values)
    045    {
    046        assert enumClass != null;
    047        assert messages != null;
    048        if (!Enum.class.isAssignableFrom(enumClass))
    049        {
    050            throw new IllegalArgumentException("Cannot create " + this.getClass().getSimpleName()
    051                + " from " + enumClass.getName() + ", not an enum class.");
    052        }
    053        String prefix = enumClass.getSimpleName();
    054
    055        for (T value : values)
    056        {
    057            String label = TapestryInternalUtils.getLabelForEnum(messages, prefix, value);
    058
    059            options.add(new OptionModelImpl(label, value));
    060        }
    061    }
    062
    063    /**
    064     * Returns null.
    065     */
    066    public List<OptionGroupModel> getOptionGroups()
    067    {
    068        return null;
    069    }
    070
    071    /**
    072     * Returns the option groups created in the constructor.
    073     */
    074    public List<OptionModel> getOptions()
    075    {
    076        return options;
    077    }
    078
    079}