1 /*
   2  * Copyright (c) 2020, 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 import java.lang.instrument.ClassFileTransformer;
  26 import java.lang.instrument.IllegalClassFormatException;
  27 import java.security.ProtectionDomain;
  28 
  29 public class RedefineClassesInModuleGraphTransformer implements ClassFileTransformer {
  30     public byte[] transform(ClassLoader loader, String name, Class<?> classBeingRedefined,
  31                             ProtectionDomain pd, byte[] buffer) throws IllegalClassFormatException {
  32         System.out.println("transforming " + name);
  33 
  34         if (name.equals("java/lang/Module")  || 
  35             name.equals("java/lang/ModuleLayer")  || 
  36             name.equals("java/lang/module/ResolvedModule")) {
  37             throw new RuntimeException("Classes used by the module graph should never be transformed by Java agent");
  38         }
  39         return null;
  40     }
  41 }