    001// Copyright 2008, 2010 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.internal.services;
    016
    017import org.apache.tapestry5.NullFieldStrategy;
    018import org.apache.tapestry5.commons.util.AvailableValues;
    019import org.apache.tapestry5.commons.util.UnknownValueException;
    020import org.apache.tapestry5.services.NullFieldStrategySource;
    021
    022import java.util.Map;
    023
    024public class NullFieldStrategySourceImpl implements NullFieldStrategySource
    025{
    026    private final Map<String, NullFieldStrategy> configuration;
    027
    028    public NullFieldStrategySourceImpl(Map<String, NullFieldStrategy> configuration)
    029    {
    030        this.configuration = configuration;
    031    }
    032
    033    public NullFieldStrategy get(String name)
    034    {
    035        NullFieldStrategy result = configuration.get(name);
    036
    037        if (result != null) return result;
    038
    039        throw new UnknownValueException(String.format("Unrecognized name '%s' locating a null field strategy.", name),
    040                new AvailableValues("Configured null field strategies", configuration));
    041
    042    }
    043}