/*

  * Copyright 2009-2010 Steve Chaloner

  *

  * 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 be.objectify.led;

 import be.objectify.led.util.ContractUtils;

 import be.objectify.led.util.StringUtils;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import java.util.Properties;

 /**

  * Default implementation of {@link PropertyContext} which

  *

  * @author Steve Chaloner

  */

 public class DefaultPropertyContext implements PropertyContext

 {

     private static final Logger LOGGER = LoggerFactory.getLogger(DefaultPropertyContext.class);

     private final Properties properties = new Properties();

     public DefaultPropertyContext(Properties... properties)

     {

         ContractUtils.nonNull(properties, "properties");

         for (Properties propertiesInstance : properties)

         {

             this.properties.putAll(propertiesInstance);

         }

     }

     /** {@inheritDoc} */

     public String getValue(String propertyName)

     {

         String value = null;

         if (properties.containsKey(propertyName))

         {

             value = properties.getProperty(propertyName);

         }

         String property = System.getProperty(propertyName);

         if (!StringUtils.isEmpty(property))

         {

             value = property;

         }

         if (value != null)

         {

             LOGGER.debug("Found value [{}] for property [{}]",

                          value,

                          propertyName);

         }

         return value;

     }

 }