Java tutorial
/** * Copyright 2013 enioka. 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. */ package com.enioka.jqm.tools; import java.io.File; import java.io.FileFilter; import java.io.FileOutputStream; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URL; import java.util.Date; import java.util.Enumeration; import java.util.HashMap; import java.util.Map; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; import javax.persistence.EntityManager; import org.apache.commons.io.FileUtils; import org.apache.commons.io.FilenameUtils; import org.apache.commons.io.IOUtils; import org.apache.commons.io.filefilter.WildcardFileFilter; import org.apache.log4j.Logger; import org.jboss.shrinkwrap.resolver.api.maven.ConfigurableMavenResolverSystem; import org.slf4j.bridge.SLF4JBridgeHandler; import com.enioka.jqm.jpamodel.JobDef; import com.enioka.jqm.jpamodel.Node; /** * The cache is responsible for resolving the dependencies of a payload (from a pom, from a lib directory, ...). As the resolution is * costly, it is only done the first time and cached afterwards. <br> * Cache invalidation is done by analyzing the last modification date of the payload jar and of the lib directory (if any) on each call.<br> * There is one library cache per engine.<br> * This object is thread-safe. */ class LibraryResolverFS { private static Logger jqmlogger = Logger.getLogger(LibraryResolverFS.class); static { SLF4JBridgeHandler.removeHandlersForRootLogger(); SLF4JBridgeHandler.install(); } private static class JobDefLibrary { URL[] urls; Date loadTime; } private Map<String, JobDefLibrary> cache = new HashMap<String, LibraryResolverFS.JobDefLibrary>(); /** * * @param n * the JQM Node that holds the binaries (local node) * @param jd * the JobDefinition that should be resolved * @param em * an EM that will be used only if not in cache, to fetch the Maven repository list from the database. * @throws JqmPayloadException */ synchronized URL[] getLibraries(Node n, JobDef jd, EntityManager em) throws JqmPayloadException { if (shouldLoad(n, jd)) { loadCache(n, jd, em); } return cache.get(jd.getApplicationName()).urls; } /** * Returns true if the libraries should be loaded in cache. Two cases: never loaded and should be reloaded (jar is more recent than * cache) */ private boolean shouldLoad(Node node, JobDef jd) { if (!cache.containsKey(jd.getApplicationName())) { return true; } // If here: cache exists. JobDefLibrary libs = cache.get(jd.getApplicationName()); // Is cache stale? Date lastLoaded = libs.loadTime; File jarFile = new File(FilenameUtils.concat(new File(node.getRepo()).getAbsolutePath(), jd.getJarPath())); File jarDir = jarFile.getParentFile(); File libDir = new File(FilenameUtils.concat(jarDir.getAbsolutePath(), "lib")); if (lastLoaded.before(new Date(jarFile.lastModified())) || lastLoaded.before(new Date(jarDir.lastModified())) || lastLoaded.before(new Date(libDir.lastModified()))) { jqmlogger.info("The cache for application " + jd.getApplicationName() + " will be reloaded"); return true; } // If here, the cache is OK return false; } private void loadCache(Node node, JobDef jd, EntityManager em) throws JqmPayloadException { jqmlogger.debug("Resolving classpath for job definition " + jd.getApplicationName()); File jarFile = new File(FilenameUtils.concat(new File(node.getRepo()).getAbsolutePath(), jd.getJarPath())); File jarDir = jarFile.getParentFile(); File libDir = new File(FilenameUtils.concat(jarDir.getAbsolutePath(), "lib")); File libDirExtracted = new File(FilenameUtils.concat(jarDir.getAbsolutePath(), "libFromJar")); File pomFile = new File(FilenameUtils.concat(jarDir.getAbsolutePath(), "pom.xml")); if (!jarFile.canRead()) { jqmlogger.warn("Cannot read file at " + jarFile.getAbsolutePath() + ". Job instance will crash. Check job definition or permissions on file."); throw new JqmPayloadException("File " + jarFile.getAbsolutePath() + " cannot be read"); } // POM file should be deleted if it comes from the jar file. Otherwise, it would stay into place and modifications to the internal // pom would be ignored. boolean pomFromJar = false; // 1st: if no pom, no lib dir => find a pom inside the JAR. (& copy it, we will read later) if (!pomFile.exists() && !libDir.exists()) { jqmlogger.trace("No pom inside jar directory. Checking for a pom inside the jar file"); InputStream is = null; FileOutputStream os = null; ZipFile zf = null; try { zf = new ZipFile(jarFile); Enumeration<? extends ZipEntry> zes = zf.entries(); while (zes.hasMoreElements()) { ZipEntry ze = zes.nextElement(); if (ze.getName().endsWith("pom.xml")) { is = zf.getInputStream(ze); os = new FileOutputStream(pomFile); IOUtils.copy(is, os); pomFromJar = true; break; } } } catch (Exception e) { throw new JqmPayloadException("Could not handle pom inside jar", e); } finally { IOUtils.closeQuietly(is); IOUtils.closeQuietly(os); Helpers.closeQuietly(zf); } } // 2nd: no pom, no pom inside jar, no lib dir => find a lib dir inside the jar if (!pomFile.exists() && !libDir.exists()) { jqmlogger.trace("Checking for a lib directory inside jar"); InputStream is = null; FileOutputStream os = null; ZipFile zf = null; FileUtils.deleteQuietly(libDirExtracted); try { zf = new ZipFile(jarFile); Enumeration<? extends ZipEntry> zes = zf.entries(); while (zes.hasMoreElements()) { ZipEntry ze = zes.nextElement(); if (ze.getName().startsWith("lib/") && ze.getName().endsWith(".jar")) { if (!libDirExtracted.isDirectory() && !libDirExtracted.mkdir()) { throw new JqmPayloadException("Could not extract libraries from jar"); } is = zf.getInputStream(ze); os = new FileOutputStream(FilenameUtils.concat(libDirExtracted.getAbsolutePath(), FilenameUtils.getName(ze.getName()))); IOUtils.copy(is, os); } } } catch (Exception e) { throw new JqmPayloadException("Could not handle internal lib directory", e); } finally { IOUtils.closeQuietly(is); IOUtils.closeQuietly(os); Helpers.closeQuietly(zf); } // If libs were extracted, put in cache and return if (libDirExtracted.isDirectory()) { FileFilter fileFilter = new WildcardFileFilter("*.jar"); File[] files = libDirExtracted.listFiles(fileFilter); URL[] libUrls = new URL[files.length]; try { for (int i = 0; i < files.length; i++) { libUrls[i] = files[i].toURI().toURL(); } } catch (Exception e) { throw new JqmPayloadException("Could not handle internal lib directory", e); } // Put in cache putInCache(libUrls, jd.getApplicationName()); return; } } // 3rd: if pom, use pom! if (pomFile.exists() && !libDir.exists()) { jqmlogger.trace("Reading a pom file"); ConfigurableMavenResolverSystem resolver = LibraryResolverMaven.getMavenResolver(em); // Resolve File[] depFiles = null; try { depFiles = resolver.loadPomFromFile(pomFile).importRuntimeDependencies().resolve() .withTransitivity().asFile(); } catch (IllegalArgumentException e) { // Happens when no dependencies inside pom, which is a weird use of the feature... jqmlogger.trace("No dependencies inside pom.xml file - no libs will be used", e); depFiles = new File[0]; } // Extract results URL[] tmp = LibraryResolverMaven.extractMavenResults(depFiles); // Put in cache putInCache(tmp, jd.getApplicationName()); // Cleanup if (pomFromJar && !pomFile.delete()) { jqmlogger.warn("Could not delete the temp pom file extracted from the jar."); } return; } // 4: if lib, use lib... (lib has priority over pom) if (libDir.exists()) { jqmlogger.trace( "Using the lib directory " + libDir.getAbsolutePath() + " as the source for dependencies"); FileFilter fileFilter = new WildcardFileFilter("*.jar"); File[] files = libDir.listFiles(fileFilter); URL[] tmp = new URL[files.length]; for (int i = 0; i < files.length; i++) { try { tmp[i] = files[i].toURI().toURL(); } catch (MalformedURLException e) { throw new JqmPayloadException("incorrect file inside lib directory", e); } } // Put in cache putInCache(tmp, jd.getApplicationName()); return; } throw new JqmPayloadException( "There is no lib dir or no pom.xml inside the directory containing the jar or inside the jar. The jar cannot be launched."); } private void putInCache(URL[] urls, String applicationName) { JobDefLibrary jdl = new JobDefLibrary(); jdl.loadTime = new Date(); jdl.urls = urls; this.cache.put(applicationName, jdl); } }