1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 import java.io.File;
  25 import java.io.IOException;
  26 import java.net.URL;
  27 import java.nio.file.Files;
  28 import java.security.AllPermission;
  29 import java.security.Permissions;
  30 import java.security.ProtectionDomain;
  31 
  32 
  33 /**
  34  * A custom ClassLoader to load the concrete LoggerFinder class
  35  * with all permissions.
  36  *
  37  * @author danielfuchs
  38  */
  39 public class CustomSystemClassLoader extends ClassLoader {
  40 
  41 
  42     Class<?> loggerFinderClass = null;
  43 
  44     public CustomSystemClassLoader() {
  45         super();
  46     }
  47     public CustomSystemClassLoader(ClassLoader parent) {
  48         super(parent);
  49     }
  50 
  51     private Class<?> defineFinderClass(String name)
  52         throws ClassNotFoundException {
  53         final Object obj = getClassLoadingLock(name);
  54         synchronized(obj) {
  55             if (loggerFinderClass != null) return loggerFinderClass;
  56 
  57             URL url = this.getClass().getProtectionDomain().getCodeSource().getLocation();
  58             File file = new File(url.getPath(), name+".class");
  59             if (file.canRead()) {
  60                 try {
  61                     byte[] b = Files.readAllBytes(file.toPath());
  62                     Permissions perms = new Permissions();
  63                     perms.add(new AllPermission());
  64                     loggerFinderClass = defineClass(
  65                             name, b, 0, b.length, new ProtectionDomain(
  66                             this.getClass().getProtectionDomain().getCodeSource(),
  67                             perms));
  68                     System.out.println("Loaded " + name);
  69                     return loggerFinderClass;
  70                 } catch (Throwable ex) {
  71                     ex.printStackTrace();
  72                     throw new ClassNotFoundException(name, ex);
  73                 }
  74             } else {
  75                 throw new ClassNotFoundException(name,
  76                         new IOException(file.toPath() + ": can't read"));
  77             }
  78         }
  79     }
  80 
  81     @Override
  82     public synchronized Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException {
  83         if (name.endsWith("$LogProducerFinder")) {
  84             Class<?> c = defineFinderClass(name);
  85             if (resolve) {
  86                 resolveClass(c);
  87             }
  88             return c;
  89         }
  90         return super.loadClass(name, resolve);
  91     }
  92 
  93     @Override
  94     protected Class<?> findClass(String name) throws ClassNotFoundException {
  95         if (name.endsWith("$$LogProducerFinder")) {
  96             return defineFinderClass(name);
  97         }
  98         return super.findClass(name);
  99     }
 100 
 101 }