NullEventBus.java

/*
   Copyright (c) 2012 LinkedIn Corp.

   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.
*/

/**
 * $Id: $
 */

package com.linkedin.d2.discovery.stores.util;

import com.linkedin.d2.discovery.event.PropertyEventBus;
import com.linkedin.d2.discovery.event.PropertyEventPublisher;
import com.linkedin.d2.discovery.event.PropertyEventSubscriber;

import java.util.Set;

/**
 * @author Steven Ihde
 * @version $Revision: $
 */

public class NullEventBus<T> implements PropertyEventBus<T>
{
  @Override
  public void register(PropertyEventSubscriber<T> subscriber)
  {
    throwUnsupported();
  }

  @Override
  public void unregister(PropertyEventSubscriber<T> subscriber)
  {
    throwUnsupported();
  }

  @Override
  public void register(Set<String> propertyNames, PropertyEventSubscriber<T> subscriber)
  {
    throwUnsupported();
  }

  @Override
  public void unregister(Set<String> propertyNames, PropertyEventSubscriber<T> subscriber)
  {
    throwUnsupported();
  }

  @Override
  public void setPublisher(PropertyEventPublisher<T> publisher)
  {
    throwUnsupported();
  }

  @Override
  public void publishInitialize(String prop, T value)
  {

  }

  @Override
  public void publishAdd(String prop, T value)
  {

  }

  @Override
  public void publishRemove(String prop)
  {

  }

  private void throwUnsupported()
  {
    throw new UnsupportedOperationException("NullEventBus is only meant to receive publication events");
  }

}