    001// Copyright 2013  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.ValueEncoder;
    018import org.apache.tapestry5.commons.services.ClassPropertyAdapter;
    019import org.apache.tapestry5.commons.services.PropertyAccess;
    020import org.apache.tapestry5.commons.services.PropertyAdapter;
    021import org.apache.tapestry5.services.ValueEncoderSource;
    022import org.apache.tapestry5.services.ValueLabelProvider;
    023
    024/**
    025 * Provides a label from a property of the passed object.
    026 *
    027 * @since 5.4
    028 */
    029public class PropertyValueLabelProvider implements ValueLabelProvider<Object>
    030{
    031    private final PropertyAccess propertyAccess;
    032    private final ValueEncoderSource valueEncoderSource;
    033    private final String labelProperty;
    034
    035    public PropertyValueLabelProvider(ValueEncoderSource valueEncoderSource,
    036            PropertyAccess propertyAccess, String labelProperty)
    037    {
    038        this.valueEncoderSource = valueEncoderSource;
    039        this.propertyAccess = propertyAccess;
    040        this.labelProperty = labelProperty;
    041    }
    042
    043    @SuppressWarnings({ "unchecked", "rawtypes" })
    044    public String getLabel(Object object)
    045    {
    046        final ClassPropertyAdapter classPropertyAdapter = this.propertyAccess.getAdapter(object);
    047
    048        final PropertyAdapter propertyAdapter = classPropertyAdapter
    049                .getPropertyAdapter(labelProperty);
    050
    051        final ValueEncoder encoder = this.valueEncoderSource.getValueEncoder(propertyAdapter
    052                .getType());
    053
    054        final Object label = propertyAdapter.get(object);
    055
    056        return encoder.toClient(label);
    057    }
    058}