001/* 002 * (C) Copyright 2012 Nuxeo SA (http://nuxeo.com/) and contributors. 003 * 004 * All rights reserved. This program and the accompanying materials 005 * are made available under the terms of the GNU Lesser General Public License 006 * (LGPL) version 2.1 which accompanies this distribution, and is available at 007 * http://www.gnu.org/licenses/lgpl.html 008 * 009 * This library is distributed in the hope that it will be useful, 010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 012 * Lesser General Public License for more details. 013 * 014 * Contributors: 015 * matic 016 */ 017package org.nuxeo.osgi.util.jar; 018 019import java.io.IOException; 020import java.lang.reflect.Field; 021import java.lang.reflect.InvocationTargetException; 022import java.lang.reflect.Method; 023import java.net.URL; 024import java.util.jar.JarFile; 025 026import org.apache.commons.logging.Log; 027import org.apache.commons.logging.LogFactory; 028 029/** 030 * @author matic 031 */ 032public class JarFileFactoryCloser { 033 034 private static final Log log = LogFactory.getLog(JarFileFactoryCloser.class); 035 036 protected boolean ok; 037 038 protected Object factory; 039 040 protected Method factoryGetMethod; 041 042 protected Method factoryCloseMethod; 043 044 public JarFileFactoryCloser() { 045 try { 046 introspectClasses(); 047 } catch (ClassNotFoundException e) { 048 log.error("Cannot introspect jar file factory class", e); 049 } catch (SecurityException e) { 050 log.error("Cannot introspect jar file factory class", e); 051 } catch (NoSuchFieldException e) { 052 log.error("Cannot introspect jar file factory class", e); 053 } catch (IllegalAccessException e) { 054 log.error("Cannot introspect jar file factory class", e); 055 } catch (NoSuchMethodException e) { 056 log.error("Cannot introspect jar file factory class", e); 057 } 058 } 059 060 protected void introspectClasses() throws ClassNotFoundException, SecurityException, NoSuchFieldException, 061 IllegalAccessException, NoSuchMethodException { 062 Class<?> jarURLConnectionClass = loadClass("sun.net.www.protocol.jar.JarURLConnection"); 063 Field jarFileFactoryField = jarURLConnectionClass.getDeclaredField("factory"); 064 jarFileFactoryField.setAccessible(true); 065 factory = jarFileFactoryField.get(null); 066 Class<?> factoryClass = loadClass("sun.net.www.protocol.jar.JarFileFactory"); 067 factoryGetMethod = factoryClass.getMethod("get", new Class<?>[] { URL.class }); 068 factoryGetMethod.setAccessible(true); 069 factoryCloseMethod = factoryClass.getMethod("close", new Class<?>[] { JarFile.class }); 070 factoryCloseMethod.setAccessible(true); 071 ok = true; 072 } 073 074 protected static Class<?> loadClass(String name) throws ClassNotFoundException { 075 return URLClassLoaderCloser.class.getClassLoader().loadClass(name); 076 } 077 078 public void close(URL location) throws IOException { 079 if (!ok) { 080 return; 081 } 082 JarFile jar = null; 083 try { 084 jar = (JarFile) factoryGetMethod.invoke(factory, new Object[] { location }); 085 factoryCloseMethod.invoke(factory, jar); 086 } catch (IllegalAccessException e) { 087 throw new RuntimeException("Cannot use reflection on jar file factory", e); 088 } catch (InvocationTargetException e) { 089 throw new RuntimeException("Cannot use reflection on jar file factory", e); 090 } 091 jar.close(); 092 } 093 094}