/* Copyright 2012 Tacit Knowledge
*
* Licensed 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 com.tacitknowledge.flip.properties;
import java.util.List;
import com.tacitknowledge.flip.Environment;
import com.tacitknowledge.flip.exceptions.MissingFeatureDescriptorException;
import com.tacitknowledge.flip.model.FeatureDescriptor;
/**
* The class which manages the property readers. It is a central point to access
* all property readers. If there are two ore more property readers which could
* return the feature descriptor with the same name the property manager returns
* only the first. The order to find the feature descriptor is the same as the
* property readers are declared in the environment.
*
* @author Serghei Soloviov <ssoloviov@tacitknowledge.com>
* @author Petric Coroli <pcoroli@tacitknowledge.com>
*/
public class PropertyManager
{
private final List<PropertyReader> propertyReaders;
/**
* Constructs the property manager. All property readers are obtained from environment.
*
* @param environment the environment used to construct the property manager.
*/
public PropertyManager(final Environment environment)
{
propertyReaders = environment.getPropertyReaders();
}
/**
* Returns the feature descriptor by its name. It returns the first found in
* the list obtained from environment.
*
* @param name the name of feature.
* @return {@link FeatureDescriptor} which has the name declared.
* @throws MissingFeatureDescriptorException throws when there is no a feature
* descriptor with the name passed as a parameter.
*/
public FeatureDescriptor getFeatureDescriptor(final String name)
{
for (final PropertyReader reader : propertyReaders)
{
final FeatureDescriptor descriptor = reader.getFeatureDescriptor(name);
if (descriptor != null)
{
return descriptor;
}
}
throw new MissingFeatureDescriptorException(String.format(
"Couldn't find a feature descriptor for feature named [%s].", name));
}
}