/* * JBoss, Home of Professional Open Source * Copyright 2005, JBoss Inc., and individual contributors as indicated * by the @authors tag. See the copyright.txt in the distribution for a * full listing of individual contributors. * * This is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as * published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This software 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this software; if not, write to the Free * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA, or see the FSF site: http://www.fsf.org. */ package org.jbpm.instantiation; import java.io.ByteArrayInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.io.InputStream; import java.net.MalformedURLException; import java.net.URL; import java.net.URLConnection; import java.net.URLStreamHandler; import org.jbpm.JbpmConfiguration; import org.jbpm.JbpmContext; import org.jbpm.JbpmException; import org.jbpm.file.def.FileDefinition; import org.jbpm.graph.def.ProcessDefinition; import org.jbpm.persistence.PersistenceService; import org.jbpm.persistence.db.DbPersistenceService; public class ProcessClassLoader extends ClassLoader { private ProcessDefinition processDefinition; private long processDefinitionId; private final JbpmConfiguration jbpmConfiguration; private final URLStreamHandler urlStreamHandler = new URLStreamHandler() { protected URLConnection openConnection(URL url) throws IOException { return new ProcessUrlConnection(url); } }; private final class ProcessUrlConnection extends URLConnection { ProcessUrlConnection(URL url) { super(url); } public void connect() throws IOException { if (!connected) connected = true; } public InputStream getInputStream() throws IOException { connect(); /* * ideally, the connection would fetch the process definition and assign it to a class * field on connect(); however, that strategy "leaks" a detached process definition */ ProcessDefinition processDefinition = getProcessDefinition(); if (processDefinition == null) throw new IOException("no active jbpm context"); // having established a "connection", check whether the file exists String fileName = url.getPath(); FileDefinition fileDefinition = processDefinition.getFileDefinition(); if (fileDefinition == null || !fileDefinition.hasFile(fileName)) { throw new FileNotFoundException(fileName); } // retrieve file content byte[] fileContent = fileDefinition.getBytes(fileName); return new ByteArrayInputStream(fileContent); } } public ProcessClassLoader(ClassLoader parent, ProcessDefinition processDefinition) { this(parent, processDefinition, null); } ProcessClassLoader(ClassLoader parent, ProcessDefinition processDefinition, JbpmConfiguration jbpmConfiguration) { super(parent); // check whether the given process definition is transient long id = processDefinition.getId(); if (id != 0) { // persistent, keep id only processDefinitionId = id; // remember jbpm configuration if (jbpmConfiguration != null) { this.jbpmConfiguration = jbpmConfiguration; } else { JbpmContext jbpmContext = JbpmContext.getCurrentJbpmContext(); if (jbpmContext == null) throw new JbpmException("no active jbpm context"); this.jbpmConfiguration = jbpmContext.getJbpmConfiguration(); } } else { // transient, keep full object this.processDefinition = processDefinition; this.jbpmConfiguration = null; } } protected ProcessDefinition getProcessDefinition() { if (processDefinition != null) return processDefinition; if (jbpmConfiguration != null) { // is there an active context? JbpmContext jbpmContext = jbpmConfiguration.getCurrentJbpmContext(); if (jbpmContext != null) { // check if transaction is still active before loading process definition // https://jira.jboss.org/browse/JBPM-2918 PersistenceService persistenceService = jbpmContext.getServices() .getPersistenceService(); if (persistenceService instanceof DbPersistenceService) { DbPersistenceService dbPersistenceService = (DbPersistenceService) persistenceService; if (dbPersistenceService.isTransactionActive()) { return persistenceService.getGraphSession() .loadProcessDefinition(processDefinitionId); } } } } return null; } protected URL findResource(String name) { ProcessDefinition processDefinition = getProcessDefinition(); FileDefinition fileDefinition; if (processDefinition == null || (fileDefinition = processDefinition.getFileDefinition()) == null) return null; // skip leading slashes int off = 0; for (int len = name.length(); off < len && name.charAt(off) == '/'; off++) /* just increase offset */; // if the resource name is absolute, that is, starts with one or more slashes if (off > 0) { // then search from the root of the process archive name = name.substring(off); } else { // otherwise, if the resource is relative, search from the classes directory name = "classes/" + name; } if (!fileDefinition.hasFile(name)) return null; try { return new URL("jbpm", null, -1, name, urlStreamHandler); } catch (MalformedURLException e) { throw new JbpmException("could not create url", e); } } /** @deprecated not in use anymore */ public static class BytesUrlStreamHandler extends URLStreamHandler { private final byte[] bytes; public BytesUrlStreamHandler(byte[] bytes) { this.bytes = bytes; } protected URLConnection openConnection(URL u) throws IOException { return new BytesUrlConnection(bytes, u); } } /** @deprecated not in use anymore */ public static class BytesUrlConnection extends URLConnection { private final byte[] bytes; public BytesUrlConnection(byte[] bytes, URL u) { super(u); this.bytes = bytes; } public void connect() throws IOException { } public InputStream getInputStream() throws IOException { return new ByteArrayInputStream(bytes); } } protected Class findClass(String className) throws ClassNotFoundException { ProcessDefinition processDefinition = getProcessDefinition(); FileDefinition fileDefinition; if (processDefinition == null || (fileDefinition = processDefinition.getFileDefinition()) == null) { throw new ClassNotFoundException(className); } // look in the classes directory of the file module definition String fileName = "classes/" + className.replace('.', '/') + ".class"; byte[] classBytes = fileDefinition.getBytes(fileName); if (classBytes == null) throw new ClassNotFoundException(className); // if the class is in a package int packageIndex = className.lastIndexOf('.'); if (packageIndex != -1) { // check whether this class loader (or any ancestor) defined the package already String packageName = className.substring(0, packageIndex); if (getPackage(packageName) == null) { // define the package prior to defining the class // see https://jira.jboss.org/jira/browse/JBPM-1404 definePackage(packageName, null, null, null, processDefinition.getName(), Integer.toString(processDefinition.getVersion()), null, null); } } return defineClass(className, classBytes, 0, classBytes.length); } }