| /* |
| * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| import java.lang.instrument.ClassFileTransformer; |
| import java.lang.instrument.IllegalClassFormatException; |
| import java.lang.instrument.Instrumentation; |
| import java.security.ProtectionDomain; |
| import java.util.HashMap; |
| |
| // This is a test utility class used to transform |
| // specified classes via initial transformation (ClassFileLoadHook). |
| // Names of classes to be transformed are supplied as arguments, |
| // the phrase to be transformed is a hard-coded predefined |
| // fairly unique phrase. |
| |
| public class TransformerAgent { |
| private static String[] classesToTransform; |
| |
| |
| private static void log(String msg) { |
| System.out.println("TransformerAgent: " + msg); |
| } |
| |
| |
| // arguments are comma-separated list of classes to transform |
| public static void premain(String agentArguments, Instrumentation instrumentation) { |
| log("premain() is called, arguments = " + agentArguments); |
| classesToTransform = agentArguments.split(","); |
| instrumentation.addTransformer(new SimpleTransformer(), /*canRetransform=*/true); |
| } |
| |
| |
| public static void agentmain(String args, Instrumentation inst) throws Exception { |
| log("agentmain() is called"); |
| premain(args, inst); |
| } |
| |
| |
| static class SimpleTransformer implements ClassFileTransformer { |
| public byte[] transform(ClassLoader loader, String name, Class<?> classBeingRedefined, |
| ProtectionDomain pd, byte[] buffer) throws IllegalClassFormatException { |
| try { |
| log("SimpleTransformer called for: " + name + "@" + incrCounter(name)); |
| if (!shouldTransform(name)) |
| return null; |
| |
| log("transforming: class name = " + name); |
| int nrOfReplacements = TransformUtil.replace(buffer, TransformUtil.BeforePattern, |
| TransformUtil.AfterPattern); |
| log("replaced the string, nrOfReplacements = " + nrOfReplacements); |
| } catch (Throwable t) { |
| // The retransform native code that called this method does not propagate |
| // exceptions. Instead of getting an uninformative generic error, catch |
| // problems here and print it, then exit. |
| log("Transformation failed!"); |
| t.printStackTrace(); |
| System.exit(1); |
| } |
| return buffer; |
| } |
| |
| // Check class name pattern, since test should only transform certain classes |
| private static boolean shouldTransform(String name) { |
| for (String match : classesToTransform) { |
| if (name.matches(match)) { |
| log("shouldTransform: match-found, match = " + match); |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| } |
| |
| |
| static HashMap<String, Integer> counterMap = new HashMap<>(); |
| |
| static Integer incrCounter(String className) { |
| Integer i = counterMap.get(className); |
| if (i == null) { |
| i = new Integer(1); |
| } else { |
| i = new Integer(i.intValue() + 1); |
| } |
| counterMap.put(className, i); |
| return i; |
| } |
| } |