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<FONT color="green">001</FONT>    /**<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one<a name="line.2"></a>
<FONT color="green">003</FONT>     * or more contributor license agreements.  See the NOTICE file<a name="line.3"></a>
<FONT color="green">004</FONT>     * distributed with this work for additional information<a name="line.4"></a>
<FONT color="green">005</FONT>     * regarding copyright ownership.  The ASF licenses this file<a name="line.5"></a>
<FONT color="green">006</FONT>     * to you under the Apache License, Version 2.0 (the<a name="line.6"></a>
<FONT color="green">007</FONT>     * "License"); you may not use this file except in compliance<a name="line.7"></a>
<FONT color="green">008</FONT>     * with the License.  You may obtain a copy of the License at<a name="line.8"></a>
<FONT color="green">009</FONT>     *<a name="line.9"></a>
<FONT color="green">010</FONT>     *     http://www.apache.org/licenses/LICENSE-2.0<a name="line.10"></a>
<FONT color="green">011</FONT>     *<a name="line.11"></a>
<FONT color="green">012</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.12"></a>
<FONT color="green">013</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.13"></a>
<FONT color="green">014</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.14"></a>
<FONT color="green">015</FONT>     * See the License for the specific language governing permissions and<a name="line.15"></a>
<FONT color="green">016</FONT>     * limitations under the License.<a name="line.16"></a>
<FONT color="green">017</FONT>     */<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    package org.apache.hadoop.lib.server;<a name="line.19"></a>
<FONT color="green">020</FONT>    <a name="line.20"></a>
<FONT color="green">021</FONT>    /**<a name="line.21"></a>
<FONT color="green">022</FONT>     * Service interface for components to be managed by the {@link Server} class.<a name="line.22"></a>
<FONT color="green">023</FONT>     */<a name="line.23"></a>
<FONT color="green">024</FONT>    public interface Service {<a name="line.24"></a>
<FONT color="green">025</FONT>    <a name="line.25"></a>
<FONT color="green">026</FONT>      /**<a name="line.26"></a>
<FONT color="green">027</FONT>       * Initializes the service. This method is called once, when the<a name="line.27"></a>
<FONT color="green">028</FONT>       * {@link Server} owning the service is being initialized.<a name="line.28"></a>
<FONT color="green">029</FONT>       *<a name="line.29"></a>
<FONT color="green">030</FONT>       * @param server the server initializing the service, give access to the<a name="line.30"></a>
<FONT color="green">031</FONT>       * server context.<a name="line.31"></a>
<FONT color="green">032</FONT>       *<a name="line.32"></a>
<FONT color="green">033</FONT>       * @throws ServiceException thrown if the service could not be initialized.<a name="line.33"></a>
<FONT color="green">034</FONT>       */<a name="line.34"></a>
<FONT color="green">035</FONT>      public void init(Server server) throws ServiceException;<a name="line.35"></a>
<FONT color="green">036</FONT>    <a name="line.36"></a>
<FONT color="green">037</FONT>      /**<a name="line.37"></a>
<FONT color="green">038</FONT>       * Post initializes the service. This method is called by the<a name="line.38"></a>
<FONT color="green">039</FONT>       * {@link Server} after all services of the server have been initialized.<a name="line.39"></a>
<FONT color="green">040</FONT>       *<a name="line.40"></a>
<FONT color="green">041</FONT>       * @throws ServiceException thrown if the service could not be<a name="line.41"></a>
<FONT color="green">042</FONT>       * post-initialized.<a name="line.42"></a>
<FONT color="green">043</FONT>       */<a name="line.43"></a>
<FONT color="green">044</FONT>      public void postInit() throws ServiceException;<a name="line.44"></a>
<FONT color="green">045</FONT>    <a name="line.45"></a>
<FONT color="green">046</FONT>      /**<a name="line.46"></a>
<FONT color="green">047</FONT>       * Destroy the services.  This method is called once, when the<a name="line.47"></a>
<FONT color="green">048</FONT>       * {@link Server} owning the service is being destroyed.<a name="line.48"></a>
<FONT color="green">049</FONT>       */<a name="line.49"></a>
<FONT color="green">050</FONT>      public void destroy();<a name="line.50"></a>
<FONT color="green">051</FONT>    <a name="line.51"></a>
<FONT color="green">052</FONT>      /**<a name="line.52"></a>
<FONT color="green">053</FONT>       * Returns the service dependencies of this service. The service will be<a name="line.53"></a>
<FONT color="green">054</FONT>       * instantiated only if all the service dependencies are already initialized.<a name="line.54"></a>
<FONT color="green">055</FONT>       *<a name="line.55"></a>
<FONT color="green">056</FONT>       * @return the service dependencies.<a name="line.56"></a>
<FONT color="green">057</FONT>       */<a name="line.57"></a>
<FONT color="green">058</FONT>      public Class[] getServiceDependencies();<a name="line.58"></a>
<FONT color="green">059</FONT>    <a name="line.59"></a>
<FONT color="green">060</FONT>      /**<a name="line.60"></a>
<FONT color="green">061</FONT>       * Returns the interface implemented by this service. This interface is used<a name="line.61"></a>
<FONT color="green">062</FONT>       * the {@link Server} when the {@link Server#get(Class)} method is used to<a name="line.62"></a>
<FONT color="green">063</FONT>       * retrieve a service.<a name="line.63"></a>
<FONT color="green">064</FONT>       *<a name="line.64"></a>
<FONT color="green">065</FONT>       * @return the interface that identifies the service.<a name="line.65"></a>
<FONT color="green">066</FONT>       */<a name="line.66"></a>
<FONT color="green">067</FONT>      public Class getInterface();<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>      /**<a name="line.69"></a>
<FONT color="green">070</FONT>       * Notification callback when the server changes its status.<a name="line.70"></a>
<FONT color="green">071</FONT>       *<a name="line.71"></a>
<FONT color="green">072</FONT>       * @param oldStatus old server status.<a name="line.72"></a>
<FONT color="green">073</FONT>       * @param newStatus new server status.<a name="line.73"></a>
<FONT color="green">074</FONT>       *<a name="line.74"></a>
<FONT color="green">075</FONT>       * @throws ServiceException thrown if the service could not process the status change.<a name="line.75"></a>
<FONT color="green">076</FONT>       */<a name="line.76"></a>
<FONT color="green">077</FONT>      public void serverStatusChange(Server.Status oldStatus, Server.Status newStatus) throws ServiceException;<a name="line.77"></a>
<FONT color="green">078</FONT>    <a name="line.78"></a>
<FONT color="green">079</FONT>    }<a name="line.79"></a>




























































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