org.apache.apex.api.plugin.Event Maven / Gradle / Ivy
/**
* 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.apex.api.plugin;
import org.apache.apex.api.plugin.Event.Type;
import org.apache.hadoop.classification.InterfaceStability.Evolving;
/**
* The class represents a plugin event that is delivered to plugins to notify them of important system events.
*
* Plugins express interest in receiving events by registering handlers for the event type and their handlers receive
* the events.
* @param event type
*
* @since 3.6.0
*/
@Evolving
public interface Event
{
/**
* Marker interface for plugin event type.
*/
@Evolving
interface Type
{
}
T getType();
@Evolving
class BaseEvent implements Event
{
private T type;
protected BaseEvent(T type)
{
this.type = type;
}
public T getType()
{
return type;
}
}
}