| /** |
| * 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.hadoop.hbase.procedure; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.Set; |
| import java.util.List; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.yetus.audience.InterfaceAudience; |
| import org.apache.yetus.audience.InterfaceStability; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Provides the common setup framework and runtime services for globally |
| * barriered procedure invocation from HBase services. |
| * @param <E> the specific procedure management extension that a concrete |
| * implementation provides |
| */ |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| public abstract class ProcedureManagerHost<E extends ProcedureManager> { |
| |
| public static final String REGIONSERVER_PROCEDURE_CONF_KEY = |
| "hbase.procedure.regionserver.classes"; |
| public static final String MASTER_PROCEDURE_CONF_KEY = |
| "hbase.procedure.master.classes"; |
| |
| private static final Logger LOG = LoggerFactory.getLogger(ProcedureManagerHost.class); |
| |
| protected Set<E> procedures = new HashSet<>(); |
| |
| /** |
| * Load system procedures. Read the class names from configuration. |
| * Called by constructor. |
| */ |
| protected void loadUserProcedures(Configuration conf, String confKey) { |
| Class<?> implClass = null; |
| |
| // load default procedures from configure file |
| String[] defaultProcClasses = conf.getStrings(confKey); |
| if (defaultProcClasses == null || defaultProcClasses.length == 0) |
| return; |
| |
| List<E> configured = new ArrayList<>(); |
| for (String className : defaultProcClasses) { |
| className = className.trim(); |
| ClassLoader cl = this.getClass().getClassLoader(); |
| Thread.currentThread().setContextClassLoader(cl); |
| try { |
| implClass = cl.loadClass(className); |
| configured.add(loadInstance(implClass)); |
| LOG.info("User procedure " + className + " was loaded successfully."); |
| } catch (ClassNotFoundException e) { |
| LOG.warn("Class " + className + " cannot be found. " + |
| e.getMessage()); |
| } catch (IOException e) { |
| LOG.warn("Load procedure " + className + " failed. " + |
| e.getMessage()); |
| } |
| } |
| |
| // add entire set to the collection |
| procedures.addAll(configured); |
| } |
| |
| @SuppressWarnings("unchecked") |
| public E loadInstance(Class<?> implClass) throws IOException { |
| // create the instance |
| E impl; |
| Object o = null; |
| try { |
| o = implClass.getDeclaredConstructor().newInstance(); |
| impl = (E)o; |
| } catch (Exception e) { |
| throw new IOException(e); |
| } |
| |
| return impl; |
| } |
| |
| // Register a procedure manager object |
| public void register(E obj) { |
| procedures.add(obj); |
| } |
| |
| public Set<E> getProcedureManagers() { |
| return new HashSet<>(procedures); |
| } |
| |
| public abstract void loadProcedures(Configuration conf); |
| } |