001// Copyright 2005 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.tapestry.enhance;
016
017import org.apache.hivemind.ErrorLog;
018import org.apache.hivemind.util.Defense;
019import org.apache.tapestry.spec.IComponentSpecification;
020
021/**
022 * Injects the component's specification as the
023 * {@link org.apache.tapestry.IComponent#getSpecification() specification}property.
024 * 
025 * @author Howard M. Lewis Ship
026 * @since 4.0
027 */
028public class InjectSpecificationWorker implements EnhancementWorker
029{
030    public static final String SPECIFICATION_PROPERTY_NAME = "specification";
031
032    private ErrorLog _errorLog;
033
034    public void performEnhancement(EnhancementOperation op, IComponentSpecification spec)
035    {
036        try
037        {
038            injectSpecification(op, spec);
039        }
040        catch (Exception ex)
041        {
042            _errorLog.error(EnhanceMessages.errorAddingProperty(SPECIFICATION_PROPERTY_NAME, op
043                    .getBaseClass(), ex), spec.getLocation(), ex);
044        }
045    }
046
047    public void injectSpecification(EnhancementOperation op, IComponentSpecification spec)
048    {
049        Defense.notNull(op, "op");
050        Defense.notNull(spec, "spec");
051
052        op.claimReadonlyProperty(SPECIFICATION_PROPERTY_NAME);
053
054        String fieldName = op.addInjectedField(
055                "_$" + SPECIFICATION_PROPERTY_NAME,
056                IComponentSpecification.class,
057                spec);
058
059        EnhanceUtils.createSimpleAccessor(
060                op,
061                fieldName,
062                SPECIFICATION_PROPERTY_NAME,
063                IComponentSpecification.class,
064                spec.getLocation());
065    }
066
067    public void setErrorLog(ErrorLog errorLog)
068    {
069        _errorLog = errorLog;
070    }
071}