Mercurial > hg > graal-jvmci-8
diff jvmci/jdk.vm.ci.runtime.test/src/jdk/vm/ci/runtime/test/RedefineClassTest.java @ 22672:1bbd4a7c274b
Rename jdk.internal.jvmci to jdk.vm.ci
author | Tom Rodriguez <tom.rodriguez@oracle.com> |
---|---|
date | Thu, 08 Oct 2015 17:28:41 -0700 |
parents | jvmci/jdk.internal.jvmci.runtime.test/src/jdk/internal/jvmci/runtime/test/RedefineClassTest.java@ec96f33a101d |
children |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/jvmci/jdk.vm.ci.runtime.test/src/jdk/vm/ci/runtime/test/RedefineClassTest.java Thu Oct 08 17:28:41 2015 -0700 @@ -0,0 +1,176 @@ +/* + * Copyright (c) 2011, 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. + */ +package jdk.vm.ci.runtime.test; + +import static org.junit.Assume.assumeTrue; + +import java.io.FileOutputStream; +import java.io.IOException; +import java.io.InputStream; +import java.lang.instrument.ClassFileTransformer; +import java.lang.instrument.IllegalClassFormatException; +import java.lang.instrument.Instrumentation; +import java.lang.management.ManagementFactory; +import java.lang.reflect.Method; +import java.nio.file.Files; +import java.nio.file.Path; +import java.security.ProtectionDomain; +import java.util.Arrays; +import java.util.jar.Attributes; +import java.util.jar.JarEntry; +import java.util.jar.JarOutputStream; +import java.util.jar.Manifest; + +import javax.tools.ToolProvider; + +import jdk.vm.ci.meta.ResolvedJavaMethod; + +import org.junit.Assert; +import org.junit.Test; + +/** + * Tests that {@link ResolvedJavaMethod}s are safe in the context of class redefinition being used + * to redefine the method to which they refer. + */ +public class RedefineClassTest extends TypeUniverse { + + static class Foo { + public static Object getName() { + return "foo"; + } + } + + @Test + public void test() throws Throwable { + + Method fooMethod = Foo.class.getDeclaredMethod("getName"); + + ResolvedJavaMethod foo1 = metaAccess.lookupJavaMethod(fooMethod); + ResolvedJavaMethod foo2 = metaAccess.lookupJavaMethod(fooMethod); + + String foo1Code = Arrays.toString(foo1.getCode()); + String foo2Code = Arrays.toString(foo2.getCode()); + + Assert.assertEquals("foo", Foo.getName()); + + redefineFoo(); + System.gc(); + + // Make sure the transformation happened + Assert.assertEquals("bar", Foo.getName()); + + Assert.assertEquals(foo1Code, Arrays.toString(foo1.getCode())); + Assert.assertEquals(foo2Code, Arrays.toString(foo1.getCode())); + } + + /** + * Adds the class file bytes for a given class to a JAR stream. + */ + static void add(JarOutputStream jar, Class<?> c) throws IOException { + String name = c.getName(); + String classAsPath = name.replace('.', '/') + ".class"; + jar.putNextEntry(new JarEntry(classAsPath)); + + InputStream stream = c.getClassLoader().getResourceAsStream(classAsPath); + + int nRead; + byte[] buf = new byte[1024]; + while ((nRead = stream.read(buf, 0, buf.length)) != -1) { + jar.write(buf, 0, nRead); + } + + jar.closeEntry(); + } + + protected void redefineFoo() throws Exception { + Manifest manifest = new Manifest(); + manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0"); + Attributes mainAttrs = manifest.getMainAttributes(); + mainAttrs.putValue("Agent-Class", FooAgent.class.getName()); + mainAttrs.putValue("Can-Redefine-Classes", "true"); + mainAttrs.putValue("Can-Retransform-Classes", "true"); + + Path jar = Files.createTempFile("myagent", ".jar"); + try { + JarOutputStream jarStream = new JarOutputStream(new FileOutputStream(jar.toFile()), manifest); + add(jarStream, FooAgent.class); + add(jarStream, FooTransformer.class); + jarStream.close(); + + loadAgent(jar); + } finally { + Files.deleteIfExists(jar); + } + } + + public static void loadAgent(Path agent) throws Exception { + String vmName = ManagementFactory.getRuntimeMXBean().getName(); + int p = vmName.indexOf('@'); + assumeTrue("VM name not in <pid>@<host> format: " + vmName, p != -1); + String pid = vmName.substring(0, p); + ClassLoader cl = ToolProvider.getSystemToolClassLoader(); + Class<?> c = Class.forName("com.sun.tools.attach.VirtualMachine", true, cl); + Method attach = c.getDeclaredMethod("attach", String.class); + Method loadAgent = c.getDeclaredMethod("loadAgent", String.class, String.class); + Method detach = c.getDeclaredMethod("detach"); + Object vm = attach.invoke(null, pid); + loadAgent.invoke(vm, agent.toString(), ""); + detach.invoke(vm); + } + + public static class FooAgent { + + public static void agentmain(@SuppressWarnings("unused") String args, Instrumentation inst) throws Exception { + if (inst.isRedefineClassesSupported() && inst.isRetransformClassesSupported()) { + inst.addTransformer(new FooTransformer(), true); + Class<?>[] allClasses = inst.getAllLoadedClasses(); + for (int i = 0; i < allClasses.length; i++) { + Class<?> c = allClasses[i]; + if (c == Foo.class) { + inst.retransformClasses(new Class<?>[]{c}); + } + } + } + } + } + + /** + * This transformer replaces the first instance of the constant "foo" in the class file for + * {@link Foo} with "bar". + */ + static class FooTransformer implements ClassFileTransformer { + + @Override + public byte[] transform(ClassLoader cl, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException { + if (Foo.class.equals(classBeingRedefined)) { + String cf = new String(classfileBuffer); + int i = cf.indexOf("foo"); + Assert.assertTrue("cannot find \"foo\" constant in " + Foo.class.getSimpleName() + "'s class file", i > 0); + classfileBuffer[i] = 'b'; + classfileBuffer[i + 1] = 'a'; + classfileBuffer[i + 2] = 'r'; + } + return classfileBuffer; + } + } +}