8233091: Backout JDK-8212117: Class.forName loads a class but not linked if class is not initialized
Reviewed-by: alanb, dholmes, mchung
--- a/make/hotspot/symbols/symbols-unix Mon Nov 04 11:05:10 2019 -0800
+++ b/make/hotspot/symbols/symbols-unix Mon Nov 04 11:42:24 2019 -0800
@@ -148,7 +148,6 @@
JVM_IsThreadAlive
JVM_IsVMGeneratedMethodIx
JVM_LatestUserDefinedLoader
-JVM_LinkClass
JVM_LoadLibrary
JVM_MaxMemory
JVM_MaxObjectInspectionAge
--- a/src/hotspot/share/include/jvm.h Mon Nov 04 11:05:10 2019 -0800
+++ b/src/hotspot/share/include/jvm.h Mon Nov 04 11:42:24 2019 -0800
@@ -346,11 +346,6 @@
JNIEXPORT jclass JNICALL
JVM_FindPrimitiveClass(JNIEnv *env, const char *utf);
-/*
- * Link the 'arg' class
- */
-JNIEXPORT void JNICALL
-JVM_LinkClass(JNIEnv *env, jclass classClass, jclass arg);
/*
* Find a class from a boot class loader. Returns NULL if class not found.
--- a/src/hotspot/share/prims/jni.cpp Mon Nov 04 11:05:10 2019 -0800
+++ b/src/hotspot/share/prims/jni.cpp Mon Nov 04 11:42:24 2019 -0800
@@ -419,7 +419,7 @@
}
TempNewSymbol sym = SymbolTable::new_symbol(name);
- result = find_class_from_class_loader(env, sym, true, true, loader,
+ result = find_class_from_class_loader(env, sym, true, loader,
protection_domain, true, thread);
if (log_is_enabled(Debug, class, resolve) && result != NULL) {
@@ -3208,7 +3208,7 @@
Handle protection_domain; // null protection domain
TempNewSymbol sym = SymbolTable::new_symbol(name);
- jclass result = find_class_from_class_loader(env, sym, true, true, loader, protection_domain, true, CHECK_NULL);
+ jclass result = find_class_from_class_loader(env, sym, true, loader, protection_domain, true, CHECK_NULL);
if (log_is_enabled(Debug, class, resolve) && result != NULL) {
trace_class_resolution(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(result)));
--- a/src/hotspot/share/prims/jvm.cpp Mon Nov 04 11:05:10 2019 -0800
+++ b/src/hotspot/share/prims/jvm.cpp Mon Nov 04 11:42:24 2019 -0800
@@ -742,17 +742,6 @@
// Misc. class handling ///////////////////////////////////////////////////////////
-JVM_ENTRY(void, JVM_LinkClass(JNIEnv* env, jclass classClass, jclass arg))
- JVMWrapper("JVM_LinkClass");
-
- oop r = JNIHandles::resolve(arg);
- Klass* klass = java_lang_Class::as_Klass(r);
-
- if (!ClassForNameDeferLinking && klass->is_instance_klass()) {
- InstanceKlass::cast(klass)->link_class(CHECK);
- }
-JVM_END
-
JVM_ENTRY(jclass, JVM_GetCallerClass(JNIEnv* env))
JVMWrapper("JVM_GetCallerClass");
@@ -863,10 +852,9 @@
Handle h_loader(THREAD, loader_oop);
Handle h_prot(THREAD, protection_domain);
-
- jboolean link = !ClassForNameDeferLinking;
- jclass result = find_class_from_class_loader(env, h_name, init, link, h_loader,
+ jclass result = find_class_from_class_loader(env, h_name, init, h_loader,
h_prot, false, THREAD);
+
if (log_is_enabled(Debug, class, resolve) && result != NULL) {
trace_class_resolution(java_lang_Class::as_Klass(JNIHandles::resolve_non_null(result)));
}
@@ -903,7 +891,7 @@
}
Handle h_loader(THREAD, class_loader);
Handle h_prot (THREAD, protection_domain);
- jclass result = find_class_from_class_loader(env, h_name, init, false, h_loader,
+ jclass result = find_class_from_class_loader(env, h_name, init, h_loader,
h_prot, true, thread);
if (log_is_enabled(Debug, class, resolve) && result != NULL) {
@@ -3410,12 +3398,9 @@
// Shared JNI/JVM entry points //////////////////////////////////////////////////////////////
-jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init, jboolean link,
+jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init,
Handle loader, Handle protection_domain,
jboolean throwError, TRAPS) {
- // Initialization also implies linking - check for coherent args
- assert((init && link) || !init, "incorrect use of init/link arguments");
-
// Security Note:
// The Java level wrapper will perform the necessary security check allowing
// us to pass the NULL as the initiating class loader. The VM is responsible for
@@ -3424,11 +3409,9 @@
// if there is no security manager in 3-arg Class.forName().
Klass* klass = SystemDictionary::resolve_or_fail(name, loader, protection_domain, throwError != 0, CHECK_NULL);
- // Check if we should initialize the class (which implies linking), or just link it
+ // Check if we should initialize the class
if (init && klass->is_instance_klass()) {
klass->initialize(CHECK_NULL);
- } else if (link && klass->is_instance_klass()) {
- InstanceKlass::cast(klass)->link_class(CHECK_NULL);
}
return (jclass) JNIHandles::make_local(env, klass->java_mirror());
}
--- a/src/hotspot/share/prims/jvm_misc.hpp Mon Nov 04 11:05:10 2019 -0800
+++ b/src/hotspot/share/prims/jvm_misc.hpp Mon Nov 04 11:42:24 2019 -0800
@@ -31,8 +31,7 @@
// Useful entry points shared by JNI and JVM interface.
// We do not allow real JNI or JVM entry point to call each other.
-jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init, jboolean link,
- Handle loader, Handle protection_domain, jboolean throwError, TRAPS);
+jclass find_class_from_class_loader(JNIEnv* env, Symbol* name, jboolean init, Handle loader, Handle protection_domain, jboolean throwError, TRAPS);
void trace_class_resolution(Klass* to_class);
--- a/src/hotspot/share/runtime/globals.hpp Mon Nov 04 11:05:10 2019 -0800
+++ b/src/hotspot/share/runtime/globals.hpp Mon Nov 04 11:42:24 2019 -0800
@@ -2223,9 +2223,6 @@
"Maximum total size of NIO direct-buffer allocations") \
range(0, max_jlong) \
\
- product(bool, ClassForNameDeferLinking, false, \
- "Revert to not linking in Class.forName()") \
- \
/* Flags used for temporary code during development */ \
\
diagnostic(bool, UseNewCode, false, \
--- a/src/java.base/share/classes/java/lang/Class.java Mon Nov 04 11:05:10 2019 -0800
+++ b/src/java.base/share/classes/java/lang/Class.java Mon Nov 04 11:42:24 2019 -0800
@@ -392,10 +392,6 @@
*
* @see java.lang.Class#forName(String)
* @see java.lang.ClassLoader
- *
- * @jls 12.2 Loading of Classes and Interfaces
- * @jls 12.3 Linking of Classes and Interfaces
- * @jls 12.4 Initialization of Classes and Interfaces
* @since 1.2
*/
@CallerSensitive
@@ -442,10 +438,6 @@
* <p> This method does not check whether the requested class is
* accessible to its caller. </p>
*
- * <p> Note that this method throws errors related to loading and linking as
- * specified in Sections 12.2 and 12.3 of <em>The Java Language
- * Specification</em>.
- *
* @apiNote
* This method returns {@code null} on failure rather than
* throwing a {@link ClassNotFoundException}, as is done by
@@ -473,8 +465,6 @@
* in a module.</li>
* </ul>
*
- * @jls 12.2 Loading of Classes and Interfaces
- * @jls 12.3 Linking of Classes and Interfaces
* @since 9
* @spec JPMS
*/
@@ -498,21 +488,13 @@
cl = module.getClassLoader();
}
- Class<?> ret;
if (cl != null) {
- ret = cl.loadClass(module, name);
+ return cl.loadClass(module, name);
} else {
- ret = BootLoader.loadClass(module, name);
+ return BootLoader.loadClass(module, name);
}
- if (ret != null) {
- // The loaded class should also be linked
- linkClass(ret);
- }
- return ret;
}
- private static native void linkClass(Class<?> c);
-
/**
* Creates a new instance of the class represented by this {@code Class}
* object. The class is instantiated as if by a {@code new}
--- a/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Mon Nov 04 11:05:10 2019 -0800
+++ b/src/java.base/share/classes/java/lang/invoke/MethodHandles.java Mon Nov 04 11:42:24 2019 -0800
@@ -1933,17 +1933,12 @@
}
/**
- * Looks up a class by name from the lookup context defined by this {@code Lookup} object.
- * This method attempts to locate, load, and link the class, and then determines whether
- * the class is accessible to this {@code Lookup} object. The static
+ * Looks up a class by name from the lookup context defined by this {@code Lookup} object. The static
* initializer of the class is not run.
* <p>
* The lookup context here is determined by the {@linkplain #lookupClass() lookup class}, its class
- * loader, and the {@linkplain #lookupModes() lookup modes}.
- * <p>
- * Note that this method throws errors related to loading and linking as
- * specified in Sections 12.2 and 12.3 of <em>The Java Language
- * Specification</em>.
+ * loader, and the {@linkplain #lookupModes() lookup modes}. In particular, the method first attempts to
+ * load the requested class, and then determines whether the class is accessible to this lookup object.
*
* @param targetName the fully qualified name of the class to be looked up.
* @return the requested class.
@@ -1955,9 +1950,6 @@
* modes.
* @throws SecurityException if a security manager is present and it
* <a href="MethodHandles.Lookup.html#secmgr">refuses access</a>
- *
- * @jls 12.2 Loading of Classes and Interfaces
- * @jls 12.3 Linking of Classes and Interfaces
* @since 9
*/
public Class<?> findClass(String targetName) throws ClassNotFoundException, IllegalAccessException {
--- a/src/java.base/share/classes/sun/launcher/LauncherHelper.java Mon Nov 04 11:05:10 2019 -0800
+++ b/src/java.base/share/classes/sun/launcher/LauncherHelper.java Mon Nov 04 11:42:24 2019 -0800
@@ -62,7 +62,6 @@
import java.nio.file.DirectoryStream;
import java.nio.file.Files;
import java.nio.file.Path;
-import java.security.AccessControlException;
import java.text.Normalizer;
import java.text.MessageFormat;
import java.util.ArrayList;
@@ -725,9 +724,6 @@
} catch (LinkageError le) {
abort(null, "java.launcher.module.error3", mainClass, m.getName(),
le.getClass().getName() + ": " + le.getLocalizedMessage());
- } catch (AccessControlException ace) {
- abort(ace, "java.launcher.module.error5", mainClass, m.getName(),
- ace.getClass().getName(), ace.getLocalizedMessage());
}
if (c == null) {
abort(null, "java.launcher.module.error2", mainClass, mainModule);
@@ -784,9 +780,6 @@
} catch (LinkageError le) {
abort(le, "java.launcher.cls.error6", cn,
le.getClass().getName() + ": " + le.getLocalizedMessage());
- } catch (AccessControlException ace) {
- abort(ace, "java.launcher.cls.error7", cn,
- ace.getClass().getName(), ace.getLocalizedMessage());
}
return mainClass;
}
--- a/src/java.base/share/native/libjava/Class.c Mon Nov 04 11:05:10 2019 -0800
+++ b/src/java.base/share/native/libjava/Class.c Mon Nov 04 11:42:24 2019 -0800
@@ -73,7 +73,6 @@
{"getRawTypeAnnotations", "()" BA, (void *)&JVM_GetClassTypeAnnotations},
{"getNestHost0", "()" CLS, (void *)&JVM_GetNestHost},
{"getNestMembers0", "()[" CLS, (void *)&JVM_GetNestMembers},
- {"linkClass", "(" CLS ")V", (void *)&JVM_LinkClass},
};
#undef OBJ
--- a/test/hotspot/jtreg/gc/logging/TestMetaSpaceLog.java Mon Nov 04 11:05:10 2019 -0800
+++ b/test/hotspot/jtreg/gc/logging/TestMetaSpaceLog.java Mon Nov 04 11:42:24 2019 -0800
@@ -130,7 +130,7 @@
public static void loadClass(WhiteBox wb) {
try {
URLClassLoader ucl = new URLClassLoader(urls);
- ucl.loadClass("case00");
+ Class.forName("case00", false, ucl);
} catch (Exception e) {
e.printStackTrace();
}
--- a/test/hotspot/jtreg/serviceability/jvmti/ClassStatus/ClassStatus.java Mon Nov 04 11:05:10 2019 -0800
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,92 +0,0 @@
-/*
- * Copyright (c) 2019, 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 8212117
- * @summary Verify JVMTI GetClassStatus returns CLASS_PREPARE after call to Class.forName()
- * @run main/othervm/native -agentlib:ClassStatus ClassStatus
- */
-
-
-public class ClassStatus {
- static {
- try {
- System.out.println("ClassStatus static block");
- System.loadLibrary("ClassStatus");
- } catch (UnsatisfiedLinkError ule) {
- System.err.println("Could not load ClassStatus library");
- System.err.println("java.library.path: "
- + System.getProperty("java.library.path"));
- throw ule;
- }
- }
-
- static native int check(Class klass);
-
- public static void main(String[] args) throws ClassNotFoundException {
- ClassLoader loader = ClassStatus.class.getClassLoader();
- Module module = loader.getUnnamedModule();
-
- // Load class, but don't initialize it
- Class foo2 = Class.forName(module, "Foo2");
- Class foo3 = Class.forName("Foo3", false, loader);
-
- System.out.println("Loaded: " + foo2);
- System.out.println("Loaded: " + foo3);
-
- int status2 = check(foo2);
- int status3 = check(foo3);
-
- new Foo2().bar();
- new Foo3().bar();
-
- if (status2 != 0) {
- System.out.println("The agent returned non-zero exit status for Foo2: " + status2);
- }
- if (status3 != 0) {
- System.out.println("The agent returned non-zero exit status for Foo3: " + status3);
- }
- if (status2 != 0 || status3 != 0) {
- throw new RuntimeException("Non-zero status returned from the agent");
- }
- }
-}
-
-class Foo2 {
- static {
- System.out.println("Foo2 is initialized");
- }
- void bar() {
- System.out.println("Foo2.bar() is called");
- }
-}
-
-class Foo3 {
- static {
- System.out.println("Foo3 is initialized");
- }
- void bar() {
- System.out.println("Foo3.bar() is called");
- }
-}
--- a/test/hotspot/jtreg/serviceability/jvmti/ClassStatus/libClassStatus.c Mon Nov 04 11:05:10 2019 -0800
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,173 +0,0 @@
-/*
- * Copyright (c) 2019, 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.
- */
-
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include "jvmti.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#ifndef JNI_ENV_ARG
-
-#ifdef __cplusplus
-#define JNI_ENV_ARG(x, y) y
-#define JNI_ENV_PTR(x) x
-#else
-#define JNI_ENV_ARG(x,y) x, y
-#define JNI_ENV_PTR(x) (*x)
-#endif
-
-#endif
-
-#define PASSED 0
-#define FAILED 2
-
-static jvmtiEnv* jvmti = NULL;
-
-static jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved);
-
-JNIEXPORT jint JNICALL
-Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
- return Agent_Initialize(jvm, options, reserved);
-}
-
-JNIEXPORT jint JNICALL
-Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
- return Agent_Initialize(jvm, options, reserved);
-}
-
-JNIEXPORT jint JNICALL
-JNI_OnLoad(JavaVM *jvm, void *reserved) {
- return JNI_VERSION_9;
-}
-
-static void
-check_jvmti_error(jvmtiEnv *jvmti, char* fname, jvmtiError err) {
- if (err != JVMTI_ERROR_NONE) {
- printf(" ## %s error: %d\n", fname, err);
- fflush(0);
- exit(err);
- }
-}
-
-static char*
-get_class_signature(jvmtiEnv *jvmti, jclass klass) {
- char* sign = NULL;
- jvmtiError err = (*jvmti)->GetClassSignature(jvmti, klass, &sign, NULL);
-
- check_jvmti_error(jvmti, "GetClassSignature", err);
- return sign;
-}
-
-static jboolean
-is_class_status_prepared(jvmtiEnv *jvmti, jclass klass) {
- char* sign = get_class_signature(jvmti, klass);
- jint status = 0;
- jvmtiError err = (*jvmti)->GetClassStatus(jvmti, klass, &status);
-
- check_jvmti_error(jvmti, "GetClassStatus", err);
- printf(" Class %s status: 0x%08x\n", sign, status);
- printf(" Class %s is prepared: %d\n", sign, (status & JVMTI_CLASS_STATUS_PREPARED) != 0);
- fflush(0);
-
- return (status & JVMTI_CLASS_STATUS_PREPARED) != 0;
-}
-
-static jboolean
-is_class_in_loaded_classes(JNIEnv *env, jclass klass) {
- char* sign = get_class_signature(jvmti, klass);
- jint class_count = 0;
- jclass* classes = NULL;
- jvmtiError err = (*jvmti)->GetLoadedClasses(jvmti, &class_count, &classes);
-
- check_jvmti_error(jvmti, "GetLoadedClasses", err);
-
- for (int i = 0; i < class_count; i++) {
- jclass cls = classes[i];
- jboolean same = (*env)->IsSameObject(env, cls, klass);
- if (same) {
- printf("Found class %s in the list of loaded classes\n", sign);
- fflush(0);
- return JNI_TRUE;
- }
- }
- printf("Error: Have not found class %s in the list of loaded classes\n", sign);
- fflush(0);
- return JNI_FALSE;
-}
-
-static void JNICALL
-ClassPrepare(jvmtiEnv *jvmti, JNIEnv *env, jthread thread, jclass klass) {
- char* sign = get_class_signature(jvmti, klass);
-
- sign = (sign == NULL) ? "NULL" : sign;
-
- if (strcmp(sign, "LFoo2;") == 0 || strcmp(sign, "LFoo3;") == 0) {
- printf("ClassPrepare event for class: %s\n", sign);
- fflush(0);
- }
-}
-
-static jint
-Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
- jvmtiError err;
- jint size;
- jint res;
- jvmtiEventCallbacks callbacks;
-
- printf("Agent_Initialize started\n");
- fflush(0);
- res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti), JVMTI_VERSION_9);
- if (res != JNI_OK || jvmti == NULL) {
- printf("## Agent_Initialize: Error in GetEnv: res: %d, jvmti env: %p\n", res, jvmti);
- return JNI_ERR;
- }
-
- size = (jint)sizeof(callbacks);
- memset(&callbacks, 0, size);
- callbacks.ClassPrepare = ClassPrepare;
-
- err = (*jvmti)->SetEventCallbacks(jvmti, &callbacks, size);
- check_jvmti_error(jvmti, "## Agent_Initialize: SetEventCallbacks", err);
-
- err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE, JVMTI_EVENT_CLASS_PREPARE, NULL);
- check_jvmti_error(jvmti, "## Agent_Initialize: SetEventNotificationMode CLASS_PREPARE", err);
- return JNI_OK;
-}
-
-JNIEXPORT jint JNICALL
-Java_ClassStatus_check(JNIEnv *env, jclass cls, jclass klass) {
- if (is_class_in_loaded_classes(env, klass) != JNI_TRUE ||
- is_class_status_prepared(jvmti, klass) != JNI_TRUE) {
- return FAILED;
- }
- return PASSED;
-}
-
-#ifdef __cplusplus
-}
-#endif