Java tutorial
/* * The MIT License (MIT) * * Copyright (c) 2014 Jeff Nelson, Cinchapi Software Collective * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package org.cinchapi.concourse.server.upgrade; import java.util.Set; import org.cinchapi.concourse.server.GlobalState; import org.cinchapi.concourse.server.upgrade.task.Upgrade2; import org.cinchapi.concourse.util.Logger; import org.reflections.Reflections; import com.google.common.collect.Sets; import static org.cinchapi.concourse.server.upgrade.UpgradeTask.getCurrentSystemVersion; /** * The {@link Upgrader} is responsible for running the latest upgrade tasks on * the storage directories. This script is typically called when a user upgrades * ConcourseServer from one version to the next. * * @author jnelson */ public class Upgrader { static { Reflections.log = null; // turn off logging } /** * The package that contains all upgrade tasks. */ private static final String[] pkgs = { "org.cinchapi.concourse.server.upgrade.task" }; /** * Run the program... * * @param args * @throws ReflectiveOperationException */ public static void main(String... args) throws ReflectiveOperationException { // Temporarily turn on console logging so the user can see the log // messages while the upgrades happen. Although we revert the setting // after the tasks have finished, console logging will be enabled for // the duration of this JVM's lifecycle. That should be okay as long as // the Upgrader runs in a different JVM that the normal ConcourseServer // process. boolean enableConsoleLogging = GlobalState.ENABLE_CONSOLE_LOGGING; GlobalState.ENABLE_CONSOLE_LOGGING = true; try { int currentSystemVersion = getCurrentSystemVersion(); // Find the new upgrade tasks Set<UpgradeTask> tasks = Sets.newTreeSet(); for (String pkg : pkgs) { Reflections reflections = new Reflections(pkg); Set<Class<? extends UpgradeTask>> classes = reflections.getSubTypesOf(UpgradeTask.class); classes.addAll(reflections.getSubTypesOf(SmartUpgradeTask.class)); for (Class<? extends UpgradeTask> clazz : classes) { UpgradeTask task = clazz.newInstance(); if (task.version() > currentSystemVersion) { tasks.add(task); } } } // Run the new upgrade tasks for (UpgradeTask task : tasks) { System.out.println(task); try { task.run(); } catch (Exception e) { if (task instanceof Upgrade2) { // CON-137: Even if Upgrade2 fails and we can't migrate // data, still set the system version so we aren't // blocked on this task in the future. UpgradeTask.setCurrentSystemVersion(task.version()); Logger.info("Due to a bug in a previous " + "release, the system version has " + "been force upgraded " + "to {}", task.version()); } else { System.exit(1); // fail fast because we assume // subsequent tasks depend on the one // that failed } } } System.exit(0); } finally { GlobalState.ENABLE_CONSOLE_LOGGING = enableConsoleLogging; } } }