001// Copyright 2004, 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.pageload;
016
017import java.util.Iterator;
018
019import org.apache.hivemind.ApplicationRuntimeException;
020import org.apache.tapestry.IComponent;
021import org.apache.tapestry.spec.IComponentSpecification;
022import org.apache.tapestry.spec.IParameterSpecification;
023
024/**
025 * Verify whether all required parameters in the examined component are bound, and if they are not,
026 * throw an exception.
027 * 
028 * @author mindbridge
029 * @since 3.0
030 */
031public class VerifyRequiredParametersVisitor implements IComponentVisitor
032{
033    /**
034     * @see org.apache.tapestry.pageload.IComponentVisitor#visitComponent(org.apache.tapestry.IComponent)
035     */
036    public void visitComponent(IComponent component)
037    {
038        IComponentSpecification spec = component.getSpecification();
039
040        Iterator i = spec.getRequiredParameters().iterator();
041
042        while (i.hasNext())
043        {
044            IParameterSpecification parameterSpec = (IParameterSpecification) i.next();
045
046            String name = parameterSpec.getParameterName();
047
048            if (component.getBinding(name) == null)
049                throw new ApplicationRuntimeException(PageloadMessages.requiredParameterNotBound(
050                        name,
051                        component), component, component.getLocation(), null);
052        }
053    }
054
055}