Java tutorial
/* * RHQ Management Platform * Copyright (C) 2005-2008 Red Hat, Inc. * All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation version 2 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ package org.rhq.plugins.apache; import java.io.BufferedWriter; import java.io.File; import java.io.FileWriter; import java.io.IOException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.rhq.core.domain.configuration.Configuration; import org.rhq.core.domain.configuration.PropertySimple; import org.rhq.core.domain.measurement.AvailabilityType; import org.rhq.core.pluginapi.inventory.InvalidPluginConfigurationException; import org.rhq.core.pluginapi.inventory.ResourceComponent; import org.rhq.core.pluginapi.inventory.ResourceContext; import org.rhq.core.pluginapi.operation.OperationResult; import org.rhq.plugins.apache.util.HttpdConfParser; /** * Management of a mod_jk plugin in the parent apache server * * @author Heiko W. Rupp */ public class ModJKComponent implements ResourceComponent<ApacheServerComponent> { private static final String OUTPUT_RESULT_PROP = "output"; public void start(ResourceContext<ApacheServerComponent> parentResourceContext) throws InvalidPluginConfigurationException, Exception { } public void stop() { } public AvailabilityType getAvailability() { return AvailabilityType.UP; // For now we are always up when our parent is. } /** * Delegate method to install a simple mod_jk in an apache httpd * @param serverComponent The parents server component with the configuration * @param params Params we got passed from the GUI * @return The outcome of the operation * @throws Exception see thrown exception for details; thrown exception summarizes error */ public static OperationResult installModJk(ApacheServerComponent serverComponent, Configuration params) throws Exception { StringBuilder builder = new StringBuilder(); boolean needWorkersProps = false; boolean needUriWorkers = false; // First see (what) if stuff is present File httpdConf = serverComponent.getHttpdConfFile(); String confPath = httpdConf.getAbsolutePath(); // If we can't update the file, then there is nothing left to do. if (!httpdConf.canWrite()) { throw new Exception("Httpd.conf is not writable at " + confPath); } HttpdConfParser cparser = new HttpdConfParser(); cparser.parse(confPath); // TODO back up original file try { BufferedWriter writer = null; try { writer = new BufferedWriter(new FileWriter(httpdConf, true)); if (cparser.isModJkInstalled()) { builder.append("Mod_jk is already installed\n"); if (cparser.getWorkerPropertiesFile() != null) { builder.append("Found a worker.properties file at ") .append(cparser.getWorkerPropertiesFile()); builder.append("\n"); } else needWorkersProps = true; if (cparser.getUriWorkerLocation() != null) { builder.append("Found a urimap file at ").append(cparser.getUriWorkerLocation()); } else needUriWorkers = true; } else { builder.append("No mod_jk installed yet at ").append(confPath).append("\n"); writer.append("LoadModule jk_module modules/mod_jk.so"); // TODO obtain modules location writer.newLine(); builder.append(".. written a LoadModule line \n"); needWorkersProps = true; needUriWorkers = true; } if (needWorkersProps) { writer.append("JkWorkersFile ").append("conf/workers.properties"); writer.newLine(); builder.append(".. installed worker.properties"); } if (needUriWorkers) { writer.append("JkMountFile ").append("conf/uriworkermap"); writer.newLine(); builder.append(".. installed uriworkermap"); } } finally { if (writer != null) { // close automatically flushes! writer.close(); } } } catch (IOException e) { builder.append("Error when installing mod_jk: \n"); builder.append(e.fillInStackTrace()); throw new Exception(builder.toString()); } OperationResult result = new OperationResult(); Configuration complexResults = result.getComplexResults(); complexResults.put(new PropertySimple(OUTPUT_RESULT_PROP, builder.toString())); return result; } }