/*
* 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.felix.ipojo;
/**
* This class defines instance state listeners.
* An instance state listener is notified of instance state changes. It needs to be
* registered on the instance by invoking the ({@link ComponentInstance#addInstanceStateListener(InstanceStateListener)}
* method. Once registered, the listener can track instance state changes.
* Received states are:
* <li>{@link ComponentInstance#VALID}</li>
* <li>{@link ComponentInstance#INVALID}</li>
* <li>{@link ComponentInstance#STOPPED}</li>
* <li>{@link ComponentInstance#DISPOSED}</li>
* @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a>
*/
public interface InstanceStateListener {
/**
* State change listener callback method.
* Every time that a monitored instance's state changes,
* this method is called with the instance and the new state.
* @param instance the changing instance
* @param newState the new instance state
*/
void stateChanged(ComponentInstance instance, int newState);
}