1 /*
   2  * Copyright (c) 2012, 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 
  25 public class VictimClassLoader extends ClassLoader {
  26     public static long counter = 0;
  27 
  28     private int which = (int) ++counter;
  29 
  30     protected VictimClassLoader() {
  31         super(VictimClassLoader.class.getClassLoader());
  32     }
  33 
  34     protected Class loadClass(String name, boolean resolve) throws ClassNotFoundException {
  35         Class c;
  36         if (!name.endsWith("Victim")) {
  37             c = super.loadClass(name, resolve);
  38             return c;
  39         }
  40 
  41         c = findLoadedClass(name);
  42         if (c != null) {
  43             return c;
  44         }
  45 
  46         byte[] buf = readClassFile(name);
  47         c = defineClass(name, buf, 0, buf.length);
  48         resolveClass(c);
  49 
  50         if (c.getClassLoader() != this) {
  51             throw new AssertionError();
  52         }
  53 
  54         Test8003720.println("loaded " + c + "#" + System.identityHashCode(c) + " in " + c.getClassLoader());
  55         return c;
  56     }
  57 
  58     static byte[] readClassFile(String name) {
  59         try {
  60             String rname = name.substring(name.lastIndexOf('.') + 1) + ".class";
  61             java.net.URL url = VictimClassLoader.class.getResource(rname);
  62             Test8003720.println("found " + rname + " = " + url);
  63 
  64             java.net.URLConnection connection = url.openConnection();
  65             int contentLength = connection.getContentLength();
  66             byte[] buf = readFully(connection.getInputStream(), contentLength);
  67 
  68             return Asmator.fixup(buf);
  69         } catch (java.io.IOException ex) {
  70             throw new Error(ex);
  71         }
  72     }
  73 
  74     static byte[] readFully(java.io.InputStream in, int len) throws java.io.IOException {
  75         byte[] b = in.readAllBytes();
  76         if (len != -1 && b.length != len)
  77             throw new java.io.IOException("Expected:" + len + ", actual:" + b.length);
  78         return b;
  79     }
  80 
  81     public void finalize() {
  82         Test8003720.println("Goodbye from " + this);
  83     }
  84 
  85     public String toString() {
  86         return "VictimClassLoader#" + which;
  87     }
  88 }