/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.configuration.builder.combined;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.beanutils.DynaBean;
import org.apache.commons.beanutils.DynaClass;
import org.apache.commons.beanutils.DynaProperty;
import org.apache.commons.configuration.beanutils.BeanHelper;
/**
* <p>
* An implementation of the {@code DynaBean} interfaces which wraps multiple
* other beans.
* </p>
* <p>
* An instance of this class is constructed with a collection of beans to be
* wrapped. When reading or writing a property the wrapped bean which defines
* this property is determined, and the operation is executed on this bean.
* </p>
* <p>
* The wrapped beans should have disjunct properties. Otherwise, it is undefined
* which bean property is read or written.
* </p>
*
* @version $Id: MultiWrapDynaBean.java 1571735 2014-02-25 16:37:52Z ggregory $
* @since 2.0
*/
class MultiWrapDynaBean implements DynaBean
{
/** Stores the class of this DynaBean. */
private final DynaClass dynaClass;
/** A map which associates property names with their defining beans. */
private final Map<String, DynaBean> propsToBeans;
/**
* Creates a new instance of {@code MultiWrapDynaBean} and initializes it
* with the given collections of beans to be wrapped.
*
* @param beans the wrapped beans
*/
public MultiWrapDynaBean(Collection<?> beans)
{
propsToBeans = new HashMap<String, DynaBean>();
Collection<DynaClass> beanClasses =
new ArrayList<DynaClass>(beans.size());
for (Object bean : beans)
{
DynaBean dynaBean = createDynaBean(bean);
DynaClass beanClass = dynaBean.getDynaClass();
for (DynaProperty prop : beanClass.getDynaProperties())
{
// ensure an order of properties
if (!propsToBeans.containsKey(prop.getName()))
{
propsToBeans.put(prop.getName(), dynaBean);
}
}
beanClasses.add(beanClass);
}
dynaClass = new MultiWrapDynaClass(beanClasses);
}
/**
* {@inheritDoc} This operation is not supported by the {@code WrapDynaBean}
* objects used internally by this class. Therefore, just an exception is
* thrown.
*/
@Override
public boolean contains(String name, String key)
{
throw new UnsupportedOperationException(
"contains() operation not supported!");
}
@Override
public Object get(String name)
{
return fetchBean(name).get(name);
}
@Override
public Object get(String name, int index)
{
return fetchBean(name).get(name, index);
}
@Override
public Object get(String name, String key)
{
return fetchBean(name).get(name, key);
}
/**
* {@inheritDoc} This implementation returns an instance of
* {@code MultiWrapDynaClass}.
*/
@Override
public DynaClass getDynaClass()
{
return dynaClass;
}
/**
* {@inheritDoc} This operation is not supported by the {@code WrapDynaBean}
* objects used internally by this class. Therefore, just an exception is
* thrown.
*/
@Override
public void remove(String name, String key)
{
throw new UnsupportedOperationException(
"remove() operation not supported!");
}
@Override
public void set(String name, Object value)
{
fetchBean(name).set(name, value);
}
@Override
public void set(String name, int index, Object value)
{
fetchBean(name).set(name, index, value);
}
@Override
public void set(String name, String key, Object value)
{
fetchBean(name).set(name, key, value);
}
/**
* Returns the bean instance to which the given property belongs. If no such
* bean is found, an arbitrary bean is returned. (This causes the operation
* on this bean to fail with a meaningful error message.)
*
* @param property the property name
* @return the bean defining this property
*/
private DynaBean fetchBean(String property)
{
DynaBean dynaBean = propsToBeans.get(property);
if (dynaBean == null)
{
dynaBean = propsToBeans.values().iterator().next();
}
return dynaBean;
}
/**
* Creates a {@code DynaBean} object for the given bean.
*
* @param bean the bean
* @return the {@code DynaBean} for this bean
*/
private static DynaBean createDynaBean(Object bean)
{
if (bean instanceof DynaBean)
{
return (DynaBean) bean;
}
return BeanHelper.createWrapDynaBean(bean);
}
}