Java tutorial
package com.linkedin.databus.bootstrap.utils; /* * * Copyright 2013 LinkedIn Corp. All rights reserved * * Licensed 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. * */ import java.io.FileInputStream; import java.io.IOException; import java.sql.Connection; import java.sql.SQLException; import java.util.Properties; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.GnuParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.Option; import org.apache.commons.cli.OptionBuilder; import org.apache.commons.cli.Options; import org.apache.commons.cli.ParseException; import org.apache.log4j.ConsoleAppender; import org.apache.log4j.Logger; import org.apache.log4j.PatternLayout; import org.apache.log4j.PropertyConfigurator; import com.linkedin.databus.bootstrap.common.BootstrapConfig; import com.linkedin.databus.bootstrap.common.BootstrapConn; import com.linkedin.databus.bootstrap.common.BootstrapDBMetaDataDAO; import com.linkedin.databus.bootstrap.common.BootstrapReadOnlyConfig; import com.linkedin.databus.core.util.ConfigLoader; public class BootstrapDropSource { public static final String MODULE = BootstrapDropSource.class.getName(); public static final Logger LOG = Logger.getLogger(MODULE); public static final String HELP_OPT_LONG_NAME = "help"; public static final char HELP_OPT_CHAR = 'h'; public static final String BOOTSTRAP_DB_PROPS_OPT_LONG_NAME = "bootstrap_db_props"; public static final char BOOTSTRAP_DB_PROP_OPT_CHAR = 'p'; public static final String CMD_LINE_PROPS_OPT_LONG_NAME = "cmdline_props"; public static final char CMD_LINE_PROPS_OPT_CHAR = 'c'; public static final String LOG4J_PROPS_OPT_LONG_NAME = "log_props"; public static final char LOG4J_PROPS_OPT_CHAR = 'l'; public static final String SOURCE_ID_OPT_LONG_NAME = "source_id"; public static final char SOURCE_ID_OPT_CHAR = 's'; private static Properties _sBootstrapConfigProps = null; private int _srcId = 0; private BootstrapDBMetaDataDAO _dbDao = null; private BootstrapReadOnlyConfig _config = null; public BootstrapDropSource(BootstrapReadOnlyConfig config, int srcId) { _srcId = srcId; _config = config; } /* * @return a bootstrapDB connection object. * Note: The connection object is still owned by BootstrapConn. SO dont close it */ public Connection getConnection() { Connection conn = null; if (_dbDao == null) { LOG.info("<<<< Creating Bootstrap Connection!! >>>>"); BootstrapConn dbConn = new BootstrapConn(); try { dbConn.initBootstrapConn(false, _config.getBootstrapDBUsername(), _config.getBootstrapDBPassword(), _config.getBootstrapDBHostname(), _config.getBootstrapDBName()); _dbDao = new BootstrapDBMetaDataDAO(dbConn, _config.getBootstrapDBHostname(), _config.getBootstrapDBUsername(), _config.getBootstrapDBPassword(), _config.getBootstrapDBName(), false); } catch (Exception e) { LOG.fatal("Unable to open BootstrapDB Connection !!", e); throw new RuntimeException("Got exception when getting bootstrap DB Connection.", e); } } try { conn = _dbDao.getBootstrapConn().getDBConn(); } catch (SQLException e) { LOG.fatal("Not able to open BootstrapDB Connection !!", e); throw new RuntimeException("Got exception when getting bootstrap DB Connection.", e); } return conn; } /** * @param args */ public static void main(String[] args) throws Exception { int srcId = parseArgs(args); BootstrapConfig config = new BootstrapConfig(); ConfigLoader<BootstrapReadOnlyConfig> configLoader = new ConfigLoader<BootstrapReadOnlyConfig>("bootstrap.", config); BootstrapReadOnlyConfig staticConfig = configLoader.loadConfig(_sBootstrapConfigProps); BootstrapDropSource cleaner = new BootstrapDropSource(staticConfig, srcId); cleaner.cleanup(); } public void cleanup() throws Exception { getConnection(); _dbDao.dropSourceInDB(_srcId); } @SuppressWarnings("static-access") public static int parseArgs(String[] args) throws IOException { CommandLineParser cliParser = new GnuParser(); Option helpOption = OptionBuilder.withLongOpt(HELP_OPT_LONG_NAME).withDescription("Help screen") .create(HELP_OPT_CHAR); Option sourceIdOption = OptionBuilder.withLongOpt(SOURCE_ID_OPT_LONG_NAME) .withDescription("Source ID for which tables need to be dropped").hasArg().withArgName("Source ID") .create(SOURCE_ID_OPT_CHAR); Option dbOption = OptionBuilder.withLongOpt(BOOTSTRAP_DB_PROPS_OPT_LONG_NAME) .withDescription("Bootstrap producer properties to use").hasArg().withArgName("property_file") .create(BOOTSTRAP_DB_PROP_OPT_CHAR); Option cmdLinePropsOption = OptionBuilder.withLongOpt(CMD_LINE_PROPS_OPT_LONG_NAME) .withDescription("Cmd line override of config properties. Semicolon separated.").hasArg() .withArgName("Semicolon_separated_properties").create(CMD_LINE_PROPS_OPT_CHAR); Option log4jPropsOption = OptionBuilder.withLongOpt(LOG4J_PROPS_OPT_LONG_NAME) .withDescription("Log4j properties to use").hasArg().withArgName("property_file") .create(LOG4J_PROPS_OPT_CHAR); Options options = new Options(); options.addOption(helpOption); options.addOption(sourceIdOption); options.addOption(dbOption); options.addOption(cmdLinePropsOption); options.addOption(log4jPropsOption); CommandLine cmd = null; try { cmd = cliParser.parse(options, args); } catch (ParseException pe) { LOG.error("Bootstrap Physical Config: failed to parse command-line options.", pe); throw new RuntimeException("Bootstrap Physical Config: failed to parse command-line options.", pe); } if (cmd.hasOption(LOG4J_PROPS_OPT_CHAR)) { String log4jPropFile = cmd.getOptionValue(LOG4J_PROPS_OPT_CHAR); PropertyConfigurator.configure(log4jPropFile); LOG.info("Using custom logging settings from file " + log4jPropFile); } else { PatternLayout defaultLayout = new PatternLayout("%d{ISO8601} +%r [%t] (%p) {%c} %m%n"); ConsoleAppender defaultAppender = new ConsoleAppender(defaultLayout); Logger.getRootLogger().removeAllAppenders(); Logger.getRootLogger().addAppender(defaultAppender); LOG.info("Using default logging settings"); } if (cmd.hasOption(HELP_OPT_CHAR)) { printCliHelp(options); System.exit(0); } if (!cmd.hasOption(SOURCE_ID_OPT_CHAR)) throw new RuntimeException("Source ID is not provided"); if (!cmd.hasOption(BOOTSTRAP_DB_PROP_OPT_CHAR)) throw new RuntimeException("Bootstrap config is not provided"); String propFile = cmd.getOptionValue(BOOTSTRAP_DB_PROP_OPT_CHAR); LOG.info("Loading bootstrap DB config from properties file " + propFile); _sBootstrapConfigProps = new Properties(); FileInputStream f = new FileInputStream(propFile); try { _sBootstrapConfigProps.load(f); } finally { f.close(); } if (cmd.hasOption(CMD_LINE_PROPS_OPT_CHAR)) { String cmdLinePropString = cmd.getOptionValue(CMD_LINE_PROPS_OPT_CHAR); updatePropsFromCmdLine(_sBootstrapConfigProps, cmdLinePropString); } return Integer.parseInt(cmd.getOptionValue(SOURCE_ID_OPT_CHAR)); } private static void updatePropsFromCmdLine(Properties props, String cmdLinePropString) { String[] cmdLinePropSplit = cmdLinePropString.split(";"); for (String s : cmdLinePropSplit) { String[] onePropSplit = s.split("="); if (onePropSplit.length != 2) { LOG.error("CMD line property setting " + s + "is not valid!"); } else { LOG.info("CMD line Property overwride: " + s); props.put(onePropSplit[0], onePropSplit[1]); } } } private static void printCliHelp(Options cliOptions) { HelpFormatter helpFormatter = new HelpFormatter(); helpFormatter.printHelp("java " + BootstrapDBCleanerMain.class.getName(), cliOptions); } }