Java tutorial
/** * Copyright (C) 2013, Moss Computing Inc. * * This file is part of appkeep. * * appkeep 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; either version 2, or (at your option) * any later version. * * appkeep 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 appkeep; see the file COPYING. If not, write to the * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301 USA. * * Linking this library statically or dynamically with other modules is * making a combined work based on this library. Thus, the terms and * conditions of the GNU General Public License cover the whole * combination. * * As a special exception, the copyright holders of this library give you * permission to link this library with independent modules to produce an * executable, regardless of the license terms of these independent * modules, and to copy and distribute the resulting executable under * terms of your choice, provided that you also meet, for each linked * independent module, the terms and conditions of the license of that * module. An independent module is a module which is not derived from * or based on this library. If you modify this library, you may extend * this exception to your version of the library, but you are not * obligated to do so. If you do not wish to do so, delete this * exception statement from your version. */ package com.moss.appkeep.tools.cache; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.util.LinkedList; import java.util.List; import javax.xml.bind.JAXBException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import com.moss.appkeep.api.ComponentId; import com.moss.appkeep.api.ComponentInfo; import com.moss.appkeep.api.security.SecurityException; import com.moss.appkeep.api.select.ComponentHandlesSelector; import com.moss.appkeep.api.select.ComponentSelector; import com.moss.appkeep.api.select.DirectComponentSelector; import com.moss.identity.tools.IdProovingException; import com.moss.jaxbhelper.JAXBHelper; import com.moss.launch.components.Component; import com.moss.launch.components.ComponentType; public class AppkeepComponentCache { private final Log log = LogFactory.getLog(getClass()); private final File cacheLocation; private final JAXBHelper helper; public AppkeepComponentCache(File cacheLocation) { super(); this.cacheLocation = cacheLocation; if (!cacheLocation.exists() && !cacheLocation.mkdirs()) { throw new RuntimeException("Could not create directory : " + cacheLocation.getAbsolutePath()); } try { this.helper = new JAXBHelper(CacheEntryInfo.class); } catch (JAXBException e) { throw new RuntimeException(e); } } public static class CacheResolution { public final File localPath; public final ComponentId componentId; public CacheResolution(File localPath, ComponentId componentId) { super(); this.localPath = localPath; this.componentId = componentId; } } public File getLocal(ComponentId id, Component c) { return dataPathFor(id, c.type()); } /** * @deprecated Use resolve() instead */ @Deprecated public File get(Component c, AppkeepConnector source) throws SecurityException, IdProovingException { return resolve(c, source).localPath; } public CacheResolution resolve(Component c, AppkeepConnector source) throws SecurityException, IdProovingException { ComponentSelector selector = new ComponentHandlesSelector(c.artifactHandles()); final ComponentInfo info = source.keep().getInfo(selector, source.produceToken()); if (info == null) { throw new RuntimeException("Keep does not have component: " + c); } else { File localPath = dataPathFor(info); if (!localPath.exists()) { try { log.info("Downloading: " + c); copyAndClose( source.keep().download(new DirectComponentSelector(info.id()), source.produceToken()), new FileOutputStream(localPath)); helper.writeToFile(helper.writeToXmlString(new CacheEntryInfo(info)), metadataPathFor(info)); } catch (Exception e) { throw new RuntimeException(e); } } log.debug(localPath.getAbsolutePath()); return new CacheResolution(localPath, info.id()); } } private final File metadataPathFor(ComponentInfo c) { return new File(cacheLocation, c.id().toString() + ".info.xml"); } private final File dataPathFor(ComponentId id, ComponentType type) { return new File(cacheLocation, id.toString() + "." + type.name().toLowerCase()); } private final File dataPathFor(ComponentInfo c) { return dataPathFor(c.id(), c.type()); } private static final void copyAndClose(InputStream in, OutputStream out) throws IOException { Throwable rootError = null; List<Throwable> cleanupErrors = new LinkedList<Throwable>(); try { byte[] buffer = new byte[100 * 1024]; for (int x = in.read(buffer); x != -1; x = in.read(buffer)) { out.write(buffer, 0, x); } } catch (Throwable t) { rootError = t; } finally { try { in.close(); } catch (Exception e) { cleanupErrors.add(e); } try { out.close(); } catch (Exception e) { cleanupErrors.add(e); } } if (rootError != null || cleanupErrors.size() > 0) { if (rootError != null) { throw new RuntimeException("Error", rootError); } else { String message = "Error"; if (cleanupErrors.size() > 0) { message += " (Cleanup errors too - see logs)"; for (Throwable next : cleanupErrors) { next.printStackTrace(); } } throw new RuntimeException(message, rootError); } } } }