    001// Copyright 2010, 2011 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.transform;
    016
    017import org.apache.tapestry5.ComponentResources;
    018import org.apache.tapestry5.plastic.FieldConduit;
    019import org.apache.tapestry5.plastic.InstanceContext;
    020
    021/**
    022 * An implementation of {@link FieldConduit} for a read-only component field. Subclasses
    023 * provide an implementation of the {@link #get(Object, org.apache.tapestry5.plastic.InstanceContext)} method.
    024 *
    025 * @since 5.2.0
    026 */
    027public abstract class ReadOnlyComponentFieldConduit implements FieldConduit<Object>
    028{
    029    private final String qualifiedFieldName;
    030
    031    public ReadOnlyComponentFieldConduit(String qualifiedFieldName)
    032    {
    033        this.qualifiedFieldName = qualifiedFieldName;
    034    }
    035
    036    public ReadOnlyComponentFieldConduit(String className, String fieldName)
    037    {
    038        this(String.format("%s.%s", className, fieldName));
    039    }
    040
    041    public ReadOnlyComponentFieldConduit(ComponentResources resources, String fieldName)
    042    {
    043        this(resources.getComponentModel().getComponentClassName(), fieldName);
    044    }
    045
    046    public void set(Object instance, InstanceContext context, Object newValue)
    047    {
    048        throw new RuntimeException(String.format("Field %s is read only.", qualifiedFieldName));
    049    }
    050}