ctornqvi@8050: /*
ctornqvi@8050:  * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
ctornqvi@8050:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
ctornqvi@8050:  *
ctornqvi@8050:  * This code is free software; you can redistribute it and/or modify it
ctornqvi@8050:  * under the terms of the GNU General Public License version 2 only, as
ctornqvi@8050:  * published by the Free Software Foundation.
ctornqvi@8050:  *
ctornqvi@8050:  * This code is distributed in the hope that it will be useful, but WITHOUT
ctornqvi@8050:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
ctornqvi@8050:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
ctornqvi@8050:  * version 2 for more details (a copy is included in the LICENSE file that
ctornqvi@8050:  * accompanied this code).
ctornqvi@8050:  *
ctornqvi@8050:  * You should have received a copy of the GNU General Public License version
ctornqvi@8050:  * 2 along with this work; if not, write to the Free Software Foundation,
ctornqvi@8050:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
ctornqvi@8050:  *
ctornqvi@8050:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
ctornqvi@8050:  * or visit www.oracle.com if you need additional information or have any
ctornqvi@8050:  * questions.
ctornqvi@8050:  */
ctornqvi@8050: 
ctornqvi@8050: import java.io.PrintWriter;
ctornqvi@8050: import java.lang.instrument.*;
ctornqvi@8050: import com.oracle.java.testlibrary.*;
ctornqvi@8050: 
ctornqvi@8050: /*
ctornqvi@8050:  * Helper class to write tests that redefine classes.
ctornqvi@8050:  * When main method is run, it will create a redefineagent.jar that can be used
ctornqvi@8050:  * with the -javaagent option to support redefining classes in jtreg tests.
ctornqvi@8050:  *
ctornqvi@8050:  * See sample test in test/testlibrary_tests/RedefineClassTest.java
ctornqvi@8050:  */
ctornqvi@8050: public class RedefineClassHelper {
ctornqvi@8050: 
ctornqvi@8050:     public static Instrumentation instrumentation;
ctornqvi@8050:     public static void premain(String agentArgs, Instrumentation inst) {
ctornqvi@8050:         instrumentation = inst;
ctornqvi@8050:     }
ctornqvi@8050: 
ctornqvi@8050:     /**
ctornqvi@8050:      * Redefine a class
ctornqvi@8050:      *
ctornqvi@8050:      * @param clazz Class to redefine
ctornqvi@8050:      * @param javacode String with the new java code for the class to be redefined
ctornqvi@8050:      */
ctornqvi@8050:     public static void redefineClass(Class clazz, String javacode) throws Exception {
ctornqvi@8050:         byte[] bytecode = InMemoryJavaCompiler.compile(clazz.getName(), javacode);
ctornqvi@8050:         redefineClass(clazz, bytecode);
ctornqvi@8050:     }
ctornqvi@8050: 
ctornqvi@8050:     /**
ctornqvi@8050:      * Redefine a class
ctornqvi@8050:      *
ctornqvi@8050:      * @param clazz Class to redefine
ctornqvi@8050:      * @param bytecode byte[] with the new class
ctornqvi@8050:      */
ctornqvi@8050:     public static void redefineClass(Class clazz, byte[] bytecode) throws Exception {
ctornqvi@8050:         instrumentation.redefineClasses(new ClassDefinition(clazz, bytecode));
ctornqvi@8050:     }
ctornqvi@8050: 
ctornqvi@8050:     /**
ctornqvi@8050:      * Main method to be invoked before test to create the redefineagent.jar
ctornqvi@8050:      */
ctornqvi@8050:     public static void main(String[] args) throws Exception {
ctornqvi@8050:         ClassFileInstaller.main("RedefineClassHelper");
ctornqvi@8050: 
ctornqvi@8050:         PrintWriter pw = new PrintWriter("MANIFEST.MF");
ctornqvi@8050:         pw.println("Premain-Class: RedefineClassHelper");
ctornqvi@8050:         pw.println("Can-Redefine-Classes: true");
ctornqvi@8050:         pw.close();
ctornqvi@8050: 
ctornqvi@8050:         sun.tools.jar.Main jarTool = new sun.tools.jar.Main(System.out, System.err, "jar");
ctornqvi@8050:         if (!jarTool.run(new String[] { "-cmf", "MANIFEST.MF", "redefineagent.jar", "RedefineClassHelper.class" })) {
ctornqvi@8050:             throw new Exception("jar operation failed");
ctornqvi@8050:         }
ctornqvi@8050:     }
ctornqvi@8050: }