test/jdk/java/lang/instrument/RedefineNestmateAttr/TestNestmateAttr.java
changeset 50735 2f2af62dfac7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/java/lang/instrument/RedefineNestmateAttr/TestNestmateAttr.java	Sat Jun 23 01:32:41 2018 -0400
@@ -0,0 +1,376 @@
+/*
+ * Copyright (c) 2018, 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.
+ */
+
+/*
+ * @test
+ * @bug 8046171
+ * @summary Class redefinition must preclude changes to nest attributes
+ * @library /test/lib
+ * @modules java.base/jdk.internal.misc
+ * @modules java.compiler
+ *          java.instrument
+ *          jdk.jartool/sun.tools.jar
+ * @compile ../NamedBuffer.java
+ * @run main RedefineClassHelper
+ * @compile Host/Host.java
+ * @run main/othervm -javaagent:redefineagent.jar -Xlog:redefine+class+nestmates=trace TestNestmateAttr Host
+ * @compile HostA/Host.java
+ * @run main/othervm -javaagent:redefineagent.jar -Xlog:redefine+class+nestmates=trace TestNestmateAttr HostA
+ * @compile HostAB/Host.java
+ * @run main/othervm -javaagent:redefineagent.jar -Xlog:redefine+class+nestmates=trace TestNestmateAttr HostAB
+ * @compile HostABC/Host.java
+ * @run main/othervm -javaagent:redefineagent.jar -Xlog:redefine+class+nestmates=trace TestNestmateAttr HostABC
+ */
+
+/* Test Description
+
+The basic test class is call Host and we have variants that have zero or more
+nested classes named A, B, C etc. Each variant of Host is defined in source
+code in its own directory i.e.
+
+Host/Host.java defines zero nested classes
+HostA/Host.java defines one nested class A
+HostAB/Host.java defines two nested classes A and B (in that order)
+etc.
+
+Each Host class has the form:
+
+  public class Host {
+    public static String getID() { return "<directory name>/Host.java"; }
+
+    < zero or more empty nested classes>
+
+    public int m() {
+        return 1; // original class
+    }
+  }
+
+Under each directory is a directory "redef" with a modified version of the Host
+class that changes the ID to e.g. Host/redef/Host.java, and the method m()
+returns 2. This allows us to check we have the redefined class loaded.
+
+Using Host' to represent the redefined version we test redefinition
+combinations as follows:
+
+Host:
+  Host -> Host'  - succeeds m() returns 2
+  Host -> HostA' - fails - added a nest member
+
+HostA:
+  HostA -> HostA'  - succeeds m() returns 2
+  HostA -> Host'   - fails - removed a nest member
+  HostA -> HostAB' - fails - added a nest member
+  HostA -> HostB'  - fails - replaced a nest member
+
+HostAB:
+  HostAB -> HostAB'  - succeeds m() returns 2
+  HostAB -> HostBA'  - succeeds m() returns 2
+  HostAB -> HostA'   - fails - removed a nest member
+  HostAB -> HostABC' - fails - added a nest member
+  HostAB -> HostAC'  - fails - replaced a nest member
+
+HostABC:
+  HostABC -> HostABC'  - succeeds m() returns 2
+  HostABC -> HostACB'  - succeeds m() returns 2
+  HostABC -> HostBAC'  - succeeds m() returns 2
+  HostABC -> HostBCA'  - succeeds m() returns 2
+  HostABC -> HostCAB'  - succeeds m() returns 2
+  HostABC -> HostCBA'  - succeeds m() returns 2
+  HostABC -> HostAB'   - fails - removed a nest member
+  HostABC -> HostABCD' - fails - added a nest member
+  HostABC -> HostABD'  - fails - replaced a nest member
+
+More than three nested classes doesn't add to the code coverage so
+we stop here.
+
+Note that we always try to load the redefined version even when we expect it
+to fail.
+
+We can only directly load one class Host per classloader, so to run all the
+groups we either need to use new classloaders, or we reinvoke the test
+requesting a different primary directory. We chose the latter using
+multiple @run tags. So we preceed as follows:
+
+ @compile Host/Host.java
+ @run TestNestmateAttr Host
+ @compile HostA/Host.java  - replaces previous Host.class
+ @run TestNestmateAttr HostA
+ @compile HostAB/Host.java  - replaces previous Host.class
+ @run TestNestmateAttr HostAB
+etc.
+
+Within the test we directly compile redefined versions of the classes,
+using CompilerUtil, and then read the .class file directly as a byte[]
+to use with the RedefineClassHelper.
+
+Finally we test redefinition of the NestHost attribute - which is
+conceptually simple, but in fact very tricky to do. We do that
+when testing HostA so we can reuse the Host$A class.
+
+*/
+
+import java.io.File;
+import java.io.FileInputStream;
+import jdk.test.lib.ByteCodeLoader;
+import jdk.test.lib.compiler.CompilerUtils;
+import jdk.test.lib.compiler.InMemoryJavaCompiler;
+import static jdk.test.lib.Asserts.assertTrue;
+
+public class TestNestmateAttr {
+
+    static final String SRC = System.getProperty("test.src");
+    static final String DEST = System.getProperty("test.classes");
+    static final boolean VERBOSE = Boolean.getBoolean("verbose");
+
+    public static void main(String[] args) throws Throwable {
+        String origin = args[0];
+        System.out.println("Testing original Host class from " + origin);
+
+        // Make sure the Host class loaded directly is an original version
+        // and from the expected location
+        Host h = new Host();
+        assertTrue(h.m() == 1);
+        assertTrue(Host.getID().startsWith(origin + "/"));
+
+        String[] badTransforms;  // directories of bad classes
+        String[] goodTransforms; // directories of good classes
+
+        boolean testNestHostChanges = false;
+
+        switch (origin) {
+        case "Host":
+            badTransforms = new String[] {
+                "HostA" // add member
+            };
+            goodTransforms = new String[] {
+                origin
+            };
+            break;
+
+        case "HostA":
+            badTransforms = new String[] {
+                "Host",   // remove member
+                "HostAB", // add member
+                "HostB"   // change member
+            };
+            goodTransforms = new String[] {
+                origin
+            };
+            testNestHostChanges = true;
+            break;
+
+        case "HostAB":
+            badTransforms = new String[] {
+                "HostA",   // remove member
+                "HostABC", // add member
+                "HostAC"   // change member
+            };
+            goodTransforms = new String[] {
+                origin,
+                "HostBA"  // reorder members
+            };
+            break;
+
+        case "HostABC":
+            badTransforms = new String[] {
+                "HostAB",   // remove member
+                "HostABCD", // add member
+                "HostABD"   // change member
+            };
+            goodTransforms = new String[] {
+                origin,
+                "HostACB",  // reorder members
+                "HostBAC",  // reorder members
+                "HostBCA",  // reorder members
+                "HostCAB",  // reorder members
+                "HostCBA"   // reorder members
+            };
+            break;
+
+        default: throw new Error("Unknown test directory: " + origin);
+        }
+
+        // Compile and check bad transformations
+        checkBadTransforms(Host.class, badTransforms);
+
+        // Compile and check good transformations
+        checkGoodTransforms(Host.class, goodTransforms);
+
+        if (testNestHostChanges)
+            checkNestHostChanges();
+    }
+
+    static void checkNestHostChanges() throws Throwable {
+        // case 1: remove NestHost attribute
+        //   - try to redefine Host$A with a top-level
+        //     class called Host$A
+        System.out.println("Trying bad retransform that removes the NestHost attribute");
+
+        String name = "Host$A";
+        // This is compiled as a top-level class: the $ in the name is not
+        // significant to the compiler.
+        String hostA = "public class " + name + " {}";
+
+        // Have to do this reflectively as there is no Host$A
+        // when compiling the "Host/" case.
+        Class<?> nestedA = Class.forName(name);
+
+        try {
+            RedefineClassHelper.redefineClass(nestedA, hostA);
+            throw new Error("Retransformation to top-level class " + name +
+                            " succeeded unexpectedly");
+        }
+        catch (UnsupportedOperationException uoe) {
+            if (uoe.getMessage().contains("attempted to change the class Nest")) {
+                System.out.println("Got expected exception " + uoe);
+            }
+            else throw new Error("Wrong UnsupportedOperationException", uoe);
+        }
+
+        // case 2: add NestHost attribute
+        //  - This is tricky because the class with no NestHost attribute
+        //    has to have the name of a nested class! Plus we need the
+        //    redefining class in bytecode form.
+        //  - Use the InMemoryJavaCompiler plus ByteCodeLoader to load
+        //    the top-level Host$A class
+        //  - Try to redefine that class with a real nested Host$A
+
+        System.out.println("Trying bad retransform that adds the NestHost attribute");
+        byte[] bytes = InMemoryJavaCompiler.compile(name, hostA);
+        Class<?> topLevelHostA = ByteCodeLoader.load(name, bytes);
+
+        byte[] nestedBytes;
+        File clsfile = new File(DEST + "/" + name + ".class");
+        if (VERBOSE) System.out.println("Reading bytes from " + clsfile);
+        try (FileInputStream str = new FileInputStream(clsfile)) {
+            nestedBytes = NamedBuffer.loadBufferFromStream(str);
+        }
+        try {
+            RedefineClassHelper.redefineClass(topLevelHostA, nestedBytes);
+            throw new Error("Retransformation to nested class " + name +
+                            " succeeded unexpectedly");
+        }
+        catch (UnsupportedOperationException uoe) {
+            if (uoe.getMessage().contains("attempted to change the class Nest")) {
+                System.out.println("Got expected exception " + uoe);
+            }
+            else throw new Error("Wrong UnsupportedOperationException", uoe);
+        }
+
+        // case 3: replace the NestHost attribute
+        //  - the easiest way (perhaps only reasonable way) to do this
+        //    is to search for the Utf8 entry used by the Constant_ClassRef,
+        //    set in the NestHost attribute, and edit it to refer to a different
+        //    name.
+        System.out.println("Trying bad retransform that changes the NestHost attribute");
+        int utf8Entry_length = 7;
+        boolean found = false;
+        for (int i = 0; i < nestedBytes.length - utf8Entry_length; i++) {
+            if (nestedBytes[i] == 1 &&   // utf8 tag
+                nestedBytes[i+1] == 0 && // msb of length
+                nestedBytes[i+2] == 4 && // lsb of length
+                nestedBytes[i+3] == (byte) 'H' &&
+                nestedBytes[i+4] == (byte) 'o' &&
+                nestedBytes[i+5] == (byte) 's' &&
+                nestedBytes[i+6] == (byte) 't') {
+
+                if (VERBOSE) System.out.println("Appear to have found Host utf8 entry starting at " + i);
+
+                nestedBytes[i+3] = (byte) 'G';
+                found = true;
+                break;
+            }
+        }
+
+        if (!found)
+            throw new Error("Could not locate 'Host' name in byte array");
+
+        try {
+            RedefineClassHelper.redefineClass(nestedA, nestedBytes);
+            throw new Error("Retransformation to modified nested class" +
+                            " succeeded unexpectedly");
+        }
+        catch (UnsupportedOperationException uoe) {
+            if (uoe.getMessage().contains("attempted to change the class Nest")) {
+                System.out.println("Got expected exception " + uoe);
+            }
+            else throw new Error("Wrong UnsupportedOperationException", uoe);
+        }
+
+    }
+
+    static void checkGoodTransforms(Class<?> c, String[] dirs) throws Throwable {
+        for (String dir : dirs) {
+            dir += "/redef";
+            System.out.println("Trying good retransform from " + dir);
+            byte[] buf = bytesForHostClass(dir);
+            RedefineClassHelper.redefineClass(c, buf);
+
+            // Test redefintion worked
+            Host h = new Host();
+            assertTrue(h.m() == 2);
+            if (VERBOSE) System.out.println("Redefined ID: " + Host.getID());
+            assertTrue(Host.getID().startsWith(dir));
+        }
+    }
+
+    static void checkBadTransforms(Class<?> c, String[] dirs) throws Throwable {
+        for (String dir : dirs) {
+            dir += "/redef";
+            System.out.println("Trying bad retransform from " + dir);
+            byte[] buf = bytesForHostClass(dir);
+            try {
+                RedefineClassHelper.redefineClass(c, buf);
+                throw new Error("Retransformation from directory " + dir +
+                                " succeeded unexpectedly");
+            }
+            catch (UnsupportedOperationException uoe) {
+                if (uoe.getMessage().contains("attempted to change the class Nest")) {
+                    System.out.println("Got expected exception " + uoe);
+                }
+                else throw new Error("Wrong UnsupportedOperationException", uoe);
+            }
+        }
+    }
+
+    static byte[] bytesForHostClass(String dir) throws Throwable {
+        compile("/" + dir);
+        File clsfile = new File(DEST + "/" + dir + "/Host.class");
+        if (VERBOSE) System.out.println("Reading bytes from " + clsfile);
+        byte[] buf = null;
+        try (FileInputStream str = new FileInputStream(clsfile)) {
+            return buf = NamedBuffer.loadBufferFromStream(str);
+        }
+    }
+
+    static void compile(String dir) throws Throwable {
+        File src = new File(SRC + dir);
+        File dst = new File(DEST + dir);
+        if (VERBOSE) System.out.println("Compiling from: " + src + "\n" +
+                                        "            to: " + dst);
+        CompilerUtils.compile(src.toPath(),
+                              dst.toPath(),
+                              false /* don't recurse */,
+                              new String[0]);
+    }
+}