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 }