001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005//     http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5.internal.bindings;
014
015import org.apache.tapestry5.Binding;
016import org.apache.tapestry5.ComponentResources;
017import org.apache.tapestry5.beanmodel.PropertyConduit;
018import org.apache.tapestry5.beanmodel.services.PropertyConduitSource;
019import org.apache.tapestry5.commons.Location;
020import org.apache.tapestry5.commons.internal.services.StringInterner;
021import org.apache.tapestry5.commons.internal.util.TapestryException;
022import org.apache.tapestry5.services.BindingFactory;
023import org.apache.tapestry5.services.pageload.PageClassLoaderContext;
024import org.apache.tapestry5.services.pageload.PageClassLoaderContextManager;
025
026/**
027 * Binding factory for reading and updating JavaBean properties.
028 *
029 * Expression are evaluated via a {@link PropertyConduit}, which is generated by {@link PropertyConduitSource} (which
030 * therefore defines the expression language).
031 */
032public class PropBindingFactory implements BindingFactory
033{
034    private final PropertyConduitSource source;
035
036    private final StringInterner interner;
037    
038    private final PageClassLoaderContextManager pageClassLoaderContextManager;
039
040    public PropBindingFactory(PropertyConduitSource propertyConduitSource, StringInterner interner,
041            PageClassLoaderContextManager pageClassLoaderContextManager)
042    {
043        source = propertyConduitSource;
044        this.interner = interner;
045        this.pageClassLoaderContextManager = pageClassLoaderContextManager;
046    }
047
048    public Binding newBinding(String description, ComponentResources container,
049                              ComponentResources component, String expression, Location location)
050    {
051        
052        Object target = container.getComponent();
053        Class targetClass = target.getClass();
054        targetClass = getClassLoaderAppropriateClass(targetClass);
055
056        PropertyConduit conduit = source.create(targetClass, expression);
057
058        String toString = interner.format("PropBinding[%s %s(%s)]", description, container
059                .getCompleteId(), expression);
060
061        return new PropBinding(location, target, conduit, expression, toString);
062    }
063
064    private Class getClassLoaderAppropriateClass(Class targetClass)
065    {
066        final String className = targetClass.getName();
067        try 
068        {
069            final PageClassLoaderContext context = pageClassLoaderContextManager.get(className);
070            targetClass = context.getProxyFactory()
071                    .getClassLoader().loadClass(className);
072        } catch (ClassNotFoundException e) 
073        {
074            throw new TapestryException(e.getMessage(), e);
075        }
076        return targetClass;
077    }
078}