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/* * Copyright 2015 JBoss Inc * * 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 io.zipi.common.plugin; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.MalformedURLException; import java.net.URL; import java.util.ArrayList; import java.util.Enumeration; import java.util.Iterator; import java.util.List; import java.util.zip.ZipEntry; import java.util.zip.ZipFile; import org.apache.commons.io.IOUtils; /** * A classloader that is capable of loading classes from an apiman * plugin artifact. * * @author eric.wittmann@redhat.com */ @SuppressWarnings("nls") public class PluginClassLoader extends ClassLoader { private ZipFile pluginArtifactZip; private List<ZipFile> dependencyZips; private File workDir; private boolean closed; /** * Constructor. * @param pluginArtifactFile plugin artifact * @throws IOException if an I/O error has occurred */ public PluginClassLoader(File pluginArtifactFile) throws IOException { super(); closed = false; this.pluginArtifactZip = new ZipFile(pluginArtifactFile); this.workDir = createWorkDir(pluginArtifactFile); indexPluginArtifact(); } /** * Constructor. * @param pluginArtifactFile plugin artifact * @param parent parent classloader * @throws IOException if an I/O error has occurred */ public PluginClassLoader(File pluginArtifactFile, ClassLoader parent) throws IOException { super(parent); this.pluginArtifactZip = new ZipFile(pluginArtifactFile); this.workDir = createWorkDir(pluginArtifactFile); indexPluginArtifact(); } /** * Creates a work directory into which various resources discovered in the plugin * artifact can be extracted. * @param pluginArtifactFile plugin artifact * @throws IOException if an I/O error has occurred */ protected File createWorkDir(File pluginArtifactFile) throws IOException { File tempDir = File.createTempFile(pluginArtifactFile.getName(), ""); tempDir.delete(); tempDir.mkdirs(); return tempDir; } /** * Indexes the content of the plugin artifact. This includes discovering all of the * dependency JARs as well as any configuration resources such as plugin definitions. * @throws IOException if an I/O error has occurred */ private void indexPluginArtifact() throws IOException { dependencyZips = new ArrayList<>(); Enumeration<? extends ZipEntry> entries = this.pluginArtifactZip.entries(); while (entries.hasMoreElements()) { ZipEntry zipEntry = entries.nextElement(); if (zipEntry.getName().startsWith("WEB-INF/lib/") && zipEntry.getName().toLowerCase().endsWith(".jar")) { ZipFile dependencyZipFile = extractDependency(zipEntry); if (dependencyZipFile != null) { dependencyZips.add(dependencyZipFile); } } } } /** * Extracts a dependency from the plugin artifact ZIP and saves it to the work * directory. If the dependency has already been extracted (we're re-using the * work directory) then this simply returns what is already there. * @param zipEntry a ZIP file entry * @throws IOException if an I/O error has occurred */ private ZipFile extractDependency(ZipEntry zipEntry) throws IOException { File dependencyWorkDir = new File(workDir, "lib"); if (!dependencyWorkDir.exists()) { dependencyWorkDir.mkdirs(); } String depFileName = new File(zipEntry.getName()).getName(); File depFile = new File(dependencyWorkDir, depFileName); if (!depFile.isFile()) { InputStream input = null; OutputStream output = null; try { input = this.pluginArtifactZip.getInputStream(zipEntry); output = new FileOutputStream(depFile); IOUtils.copy(input, output); output.flush(); } catch (IOException e) { throw e; } finally { IOUtils.closeQuietly(input); IOUtils.closeQuietly(output); } } return new ZipFile(depFile); } /** * Extracts a resource from the plugin artifact ZIP and saves it to the work * directory. If the resource has already been extracted (we're re-using the * work directory) then this simply returns what is already there. * @param zipEntry a ZIP file entry * @throws IOException if an I/O error has occurred */ private URL extractResource(ZipEntry zipEntry) throws IOException { File resourceWorkDir = new File(workDir, "resources"); if (!resourceWorkDir.exists()) { resourceWorkDir.mkdirs(); } File resourceFile = new File(resourceWorkDir, zipEntry.getName()); if (!resourceFile.isFile()) { resourceFile.getParentFile().mkdirs(); InputStream input = null; OutputStream output = null; try { input = this.pluginArtifactZip.getInputStream(zipEntry); output = new FileOutputStream(resourceFile); IOUtils.copy(input, output); output.flush(); } catch (IOException e) { throw e; } finally { IOUtils.closeQuietly(input); IOUtils.closeQuietly(output); } } return resourceFile.toURI().toURL(); } /** * @see java.lang.ClassLoader#findClass(java.lang.String) */ @Override protected Class<?> findClass(String name) throws ClassNotFoundException { InputStream inputStream = null; try { inputStream = findClassContent(name); if (inputStream == null) { return super.findClass(name); } ByteArrayOutputStream baos = new ByteArrayOutputStream(); IOUtils.copy(inputStream, baos); byte[] bytes = baos.toByteArray(); return defineClass(name, bytes, 0, bytes.length); } catch (IOException e) { throw new ClassNotFoundException(name, e); } finally { IOUtils.closeQuietly(inputStream); } } /** * Searches the plugin artifact ZIP and all dependency ZIPs for a zip entry for * the given fully qualified class name. * @param className name of class * @throws IOException if an I/O error has occurred */ protected InputStream findClassContent(String className) throws IOException { String primaryArtifactEntryName = "WEB-INF/classes/" + className.replace('.', '/') + ".class"; String dependencyEntryName = className.replace('.', '/') + ".class"; ZipEntry entry = this.pluginArtifactZip.getEntry(primaryArtifactEntryName); if (entry != null) { return this.pluginArtifactZip.getInputStream(entry); } for (ZipFile zipFile : this.dependencyZips) { entry = zipFile.getEntry(dependencyEntryName); if (entry != null) { return zipFile.getInputStream(entry); } } return null; } /** * @see java.lang.ClassLoader#findResource(java.lang.String) */ @Override protected URL findResource(String name) { Enumeration<? extends ZipEntry> entries = this.pluginArtifactZip.entries(); while (entries.hasMoreElements()) { ZipEntry zipEntry = entries.nextElement(); if (zipEntry.getName().equalsIgnoreCase(name) || zipEntry.getName().equalsIgnoreCase("WEB-INF/classes/" + name)) { try { return extractResource(zipEntry); } catch (IOException e) { throw new RuntimeException(e); } } } ZipEntry entry; File file; for (ZipFile zipFile : this.dependencyZips) { entry = zipFile.getEntry(name); if (entry != null) { try { file = new File(zipFile.getName()); URL zipUrl = file.toURI().toURL(); URL entryUrl = new URL("jar:" + zipUrl + "!/" + name); return entryUrl; } catch (MalformedURLException e) { e.printStackTrace(); } } } return super.findResource(name); } /** * @see java.lang.ClassLoader#findResources(java.lang.String) */ @Override protected Enumeration<URL> findResources(String name) throws IOException { List<URL> resources = new ArrayList<>(); // Search for the artifact in the plugin WAR itself Enumeration<? extends ZipEntry> entries = this.pluginArtifactZip.entries(); while (entries.hasMoreElements()) { ZipEntry zipEntry = entries.nextElement(); if (zipEntry.getName().equalsIgnoreCase(name)) { try { resources.add(extractResource(zipEntry)); } catch (IOException e) { throw new RuntimeException(e); } } } // Now also add any resources found in dependencies ZipEntry entry; File file; for (ZipFile zipFile : this.dependencyZips) { entry = zipFile.getEntry(name); if (entry != null) { try { file = new File(zipFile.getName()); URL zipUrl = file.toURI().toURL(); URL entryUrl = new URL("jar:" + zipUrl + "!/" + name); resources.add(entryUrl); } catch (MalformedURLException e) { e.printStackTrace(); } } } // Return the discovered resources as an Enumeration final Iterator<URL> iterator = resources.iterator(); return new Enumeration<URL>() { @Override public boolean hasMoreElements() { return iterator.hasNext(); } @Override public URL nextElement() { return iterator.next(); } }; } /** * @see java.lang.Object#finalize() */ @Override protected void finalize() throws Throwable { super.finalize(); close(); } /** * Closes any resources the plugin classloader is holding open. * @throws IOException if an I/O error has occurred */ public void close() throws IOException { if (closed) { return; } this.pluginArtifactZip.close(); for (ZipFile zipFile : this.dependencyZips) { zipFile.close(); } closed = true; } /** * @return gets any policy definition resources from the plugin artifact (located in META-INF/apiman/policyDefs/*.json */ public List<URL> getPolicyDefinitionResources() { List<URL> resources = new ArrayList<>(); Enumeration<? extends ZipEntry> entries = this.pluginArtifactZip.entries(); while (entries.hasMoreElements()) { ZipEntry zipEntry = entries.nextElement(); if (zipEntry.getName().toLowerCase().startsWith("meta-inf/apiman/policydefs/") && zipEntry.getName().toLowerCase().endsWith(".json")) { try { resources.add(extractResource(zipEntry)); } catch (IOException e) { throw new RuntimeException(e); } } } return resources; } }