Copyright 2014 Netflix, Inc.
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.
/**
 * Copyright 2014 Netflix, Inc.
 *
 * 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.netflix.config;

The interface that defines the contract between DynamicProperty and its
underlying support system.
 In most cases, it will be much easier to use Apache Commons Configuration to support DynamicProperty. However, this interface makes it possible for DynamicProperty to work without relying on Apache Commons Configuration. 
Author:
kranganathan/**
 * The interface that defines the contract between DynamicProperty and its
 * underlying support system.
 * <p>
 * In most cases, it will be much easier to use Apache Commons Configuration to 
 * support {@link DynamicProperty}. However, this interface makes it possible for
 * {@link DynamicProperty} to work without relying on Apache Commons Configuration.
 * 
 * @author kranganathan
 *
 */
public interface DynamicPropertySupport {

    
Get the string value of a given property. The string value will be further cached and parsed into specific type for DynamicProperty. 
Params:
propName – The name of the property
Returns:
The String value of the property/**
     * Get the string value of a given property. The string value will be further 
     * cached and parsed into specific type for {@link DynamicProperty}.
     * 
     * @param propName The name of the property
     * @return The String value of the property 
     */
    String getString(String propName);

    
Add the property change listener. This is necessary for the DynamicProperty to receive callback once a property is updated in the underlying DynamicPropertySupport 
Params:
expandedPropertyListener – Listener to be added to DynamicPropertySupport/**
     * Add the property change listener. This is necessary for the {@link DynamicProperty} to
     * receive callback once a property is updated in the underlying {@link DynamicPropertySupport}
     * 
     * @param expandedPropertyListener Listener to be added to {@link DynamicPropertySupport}
     */
    void addConfigurationListener(PropertyListener expandedPropertyListener);
}