Java tutorial
/** * 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.tajo.cli.tools; import com.google.protobuf.ServiceException; import org.apache.commons.cli.*; import org.apache.tajo.client.TajoClient; import org.apache.tajo.conf.TajoConf; import org.apache.tajo.service.ServiceTracker; import org.apache.tajo.service.ServiceTrackerFactory; import org.apache.tajo.util.NetUtils; import java.io.IOException; import java.io.PrintWriter; import java.io.Writer; import java.net.InetSocketAddress; public class TajoHAAdmin { private static final Options options; static { options = new Options(); options.addOption("h", "host", true, "Tajo server host"); options.addOption("p", "port", true, "Tajo server port"); options.addOption("transitionToActive", null, true, "Transitions the master into Active state"); options.addOption("transitionToBackup", null, true, "Transitions the master into Backup state"); options.addOption("getState", null, true, "Returns the state of the master"); options.addOption("formatHA", null, false, "Format HA status on share storage"); } private TajoConf tajoConf; private Writer writer; private ServiceTracker serviceTracker; public TajoHAAdmin(TajoConf tajoConf, Writer writer) { this(tajoConf, writer, null); } public TajoHAAdmin(TajoConf tajoConf, Writer writer, TajoClient tajoClient) { this.tajoConf = tajoConf; this.writer = writer; serviceTracker = ServiceTrackerFactory.get(this.tajoConf); } private void printUsage() { HelpFormatter formatter = new HelpFormatter(); formatter.printHelp("haadmin [options]", options); } public void runCommand(String[] args) throws Exception { if (args.length == 1 && (args[0].equalsIgnoreCase("-transitionToActive") || args[0].equalsIgnoreCase("-transitionToBackup") || args[0].equalsIgnoreCase("-getState"))) { writer.write("Not enough arguments: expected 1 but got 0\n"); writer.flush(); return; } CommandLineParser parser = new PosixParser(); CommandLine cmd = parser.parse(options, args); String param = ""; int cmdType = 0; String hostName = null; Integer port = null; if (cmd.hasOption("h")) { hostName = cmd.getOptionValue("h"); } if (cmd.hasOption("p")) { port = Integer.parseInt(cmd.getOptionValue("p")); } if (cmd.hasOption("transitionToActive")) { cmdType = 1; param = cmd.getOptionValue("transitionToActive"); } else if (cmd.hasOption("transitionToBackup")) { cmdType = 2; param = cmd.getOptionValue("transitionToBackup"); } else if (cmd.hasOption("getState")) { cmdType = 3; param = cmd.getOptionValue("getState"); } else if (cmd.hasOption("formatHA")) { cmdType = 4; } // if there is no "-h" option, InetSocketAddress address = tajoConf.getSocketAddrVar(TajoConf.ConfVars.TAJO_MASTER_CLIENT_RPC_ADDRESS, TajoConf.ConfVars.TAJO_MASTER_UMBILICAL_RPC_ADDRESS); if (hostName == null) { hostName = address.getHostName(); } if (port == null) { port = address.getPort(); } if (cmdType == 0) { printUsage(); return; } if ((hostName == null) ^ (port == null)) { System.err.println("ERROR: cannot find valid Tajo server address"); return; } else if (hostName != null && port != null) { tajoConf.setVar(TajoConf.ConfVars.TAJO_MASTER_CLIENT_RPC_ADDRESS, NetUtils.getHostPortString(hostName, port)); } if (!tajoConf.getBoolVar(TajoConf.ConfVars.TAJO_MASTER_HA_ENABLE)) { writer.write("HA is not enabled for this tajo cluster."); } else { switch (cmdType) { case 1: writer.write("Not Yet Implemented\n"); break; case 2: writer.write("Not Yet Implemented\n"); break; case 3: getState(writer, param); break; case 4: formatHA(writer); break; default: printUsage(); break; } } writer.flush(); } private void getState(Writer writer, String param) throws ParseException, IOException, ServiceException { int retValue = serviceTracker.getState(param, tajoConf); switch (retValue) { case 1: writer.write("The master is active.\n"); break; case 0: writer.write("The master is backup.\n"); break; case -1: writer.write("Finding failed. - master:" + param + "\n"); break; default: writer.write("Cannot find the master. - master:" + param + "\n"); break; } } private void formatHA(Writer writer) throws ParseException, IOException, ServiceException { int retValue = serviceTracker.formatHA(tajoConf); switch (retValue) { case 1: writer.write("Formatting finished successfully.\n"); break; case 0: writer.write("If you want to format the ha information, you must shutdown tajo masters " + " before formatting.\n"); break; default: writer.write("Cannot format ha information.\n"); break; } } public static void main(String[] args) throws Exception { TajoConf conf = new TajoConf(); try (Writer writer = new PrintWriter(System.out)) { TajoHAAdmin admin = new TajoHAAdmin(conf, writer); admin.runCommand(args); } finally { System.exit(0); } } }