1 /*
2 * Copyright (c) 2019, 2026, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /*
25 * @test
26 * @library /test/lib
27 *
28 * @enablePreview
29 *
30 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:-TieredCompilation -DTHROW=false -Xcheck:jni ClassInitBarrier
31 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:-TieredCompilation -DTHROW=true -Xcheck:jni ClassInitBarrier
32 *
33 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:TieredStopAtLevel=1 -DTHROW=false -XX:CompileCommand=dontinline,*::static* -Xcheck:jni ClassInitBarrier
34 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:TieredStopAtLevel=1 -DTHROW=true -XX:CompileCommand=dontinline,*::static* -Xcheck:jni ClassInitBarrier
35 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:-TieredCompilation -DTHROW=false -XX:CompileCommand=dontinline,*::static* -Xcheck:jni ClassInitBarrier
36 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:-TieredCompilation -DTHROW=true -XX:CompileCommand=dontinline,*::static* -Xcheck:jni ClassInitBarrier
37 *
38 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:TieredStopAtLevel=1 -DTHROW=false -XX:CompileCommand=exclude,*::static* -Xcheck:jni ClassInitBarrier
39 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:TieredStopAtLevel=1 -DTHROW=true -XX:CompileCommand=exclude,*::static* -Xcheck:jni ClassInitBarrier
40 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:-TieredCompilation -DTHROW=false -XX:CompileCommand=exclude,*::static* -Xcheck:jni ClassInitBarrier
41 * @run main/othervm/native -Xbatch -XX:CompileCommand=dontinline,*::test* -XX:-TieredCompilation -DTHROW=true -XX:CompileCommand=exclude,*::static* -Xcheck:jni ClassInitBarrier
42 */
43
44 import jdk.test.lib.Asserts;
45
46 import java.util.*;
47 import java.util.concurrent.atomic.AtomicBoolean;
48 import java.util.concurrent.atomic.AtomicInteger;
49 import java.util.function.Consumer;
50
51 public class ClassInitBarrier {
52 static {
53 System.loadLibrary("ClassInitBarrier");
54
55 if (!init()) {
56 throw new Error("init failed");
57 }
58 }
59
60 static native boolean init();
61
62 static final boolean THROW = Boolean.getBoolean("THROW");
63
64 static value class MyValue {
65 int x = 42;
66
67 void verify() {
68 Asserts.assertEquals(x, 42);
69 }
70 }
71
72 static class Test {
73
74 static class A {
75 static {
76 if (!init(B.class)) {
77 throw new Error("init failed");
78 }
79
80 changePhase(Phase.IN_PROGRESS);
81 runTests(); // interpreted mode
82 warmup(); // trigger compilation
83 runTests(); // compiled mode
84
85 ensureBlocked(); // ensure still blocked
86 maybeThrow(); // fail initialization if needed
87
88 changePhase(Phase.FINISHED);
89 }
90
91 static void staticM(Runnable action, MyValue val) { action.run(); val.verify(); }
92 static synchronized void staticS(Runnable action, MyValue val) { action.run(); val.verify(); }
93 static native void staticN(Runnable action, MyValue val);
94
95 static int staticF;
96
97 int f;
98 void m() {}
99
100 static native boolean init(Class<B> cls);
101 }
102
103 static class B extends A {}
104
105 static void testInvokeStatic(Runnable action, MyValue val) { A.staticM(action, val); }
106 static void testInvokeStaticSync(Runnable action, MyValue val) { A.staticS(action, val); }
107 static void testInvokeStaticNative(Runnable action, MyValue val) { A.staticN(action, val); }
108
109 static int testGetStatic(Runnable action, MyValue val) { int v = A.staticF; action.run(); val.verify(); return v; }
110 static void testPutStatic(Runnable action, MyValue val) { A.staticF = 1; action.run(); val.verify(); }
111 static A testNewInstanceA(Runnable action, MyValue val) { A obj = new A(); action.run(); val.verify(); return obj; }
112 static B testNewInstanceB(Runnable action, MyValue val) { B obj = new B(); action.run(); val.verify(); return obj; }
113
114 static int testGetField(A recv, Runnable action, MyValue val) { int v = recv.f; action.run(); val.verify(); return v; }
115 static void testPutField(A recv, Runnable action, MyValue val) { recv.f = 1; action.run(); val.verify(); }
116 static void testInvokeVirtual(A recv, Runnable action, MyValue val) { recv.m(); action.run(); val.verify(); }
117
118 static native void testInvokeStaticJNI(Runnable action, MyValue val);
119 static native void testInvokeStaticSyncJNI(Runnable action, MyValue val);
120 static native void testInvokeStaticNativeJNI(Runnable action, MyValue val);
121
122 static native int testGetStaticJNI(Runnable action, MyValue val);
123 static native void testPutStaticJNI(Runnable action, MyValue val);
124 static native A testNewInstanceAJNI(Runnable action, MyValue val);
125 static native B testNewInstanceBJNI(Runnable action, MyValue val);
126
127 static native int testGetFieldJNI(A recv, Runnable action, MyValue val);
128 static native void testPutFieldJNI(A recv, Runnable action, MyValue val);
129 static native void testInvokeVirtualJNI(A recv, Runnable action, MyValue val);
130
131 static void runTests() {
132 checkBlockingAction(Test::testInvokeStatic); // invokestatic
133 checkBlockingAction(Test::testInvokeStaticSync); // invokestatic
134 checkBlockingAction(Test::testInvokeStaticNative); // invokestatic
135 checkBlockingAction(Test::testGetStatic); // getstatic
136 checkBlockingAction(Test::testPutStatic); // putstatic
137 checkBlockingAction(Test::testNewInstanceA); // new
138
139 checkNonBlockingAction(Test::testInvokeStaticJNI); // invokestatic
140 checkNonBlockingAction(Test::testInvokeStaticSyncJNI); // invokestatic
141 checkNonBlockingAction(Test::testInvokeStaticNativeJNI); // invokestatic
142 checkNonBlockingAction(Test::testGetStaticJNI); // getstatic
143 checkNonBlockingAction(Test::testPutStaticJNI); // putstatic
144 checkBlockingAction(Test::testNewInstanceAJNI); // new
145
146 A recv = testNewInstanceB(NON_BLOCKING.get(), new MyValue()); // trigger B initialization
147 checkNonBlockingAction(Test::testNewInstanceB); // new: NO BLOCKING: same thread: A being initialized, B fully initialized
148
149 checkNonBlockingAction(recv, Test::testGetField); // getfield
150 checkNonBlockingAction(recv, Test::testPutField); // putfield
151 checkNonBlockingAction(recv, Test::testInvokeVirtual); // invokevirtual
152
153 checkNonBlockingAction(Test::testNewInstanceBJNI); // new: NO BLOCKING: same thread: A being initialized, B fully initialized
154 checkNonBlockingAction(recv, Test::testGetFieldJNI); // getfield
155 checkNonBlockingAction(recv, Test::testPutFieldJNI); // putfield
156 checkNonBlockingAction(recv, Test::testInvokeVirtualJNI); // invokevirtual
157 }
158
159 static void warmup() {
160 MyValue val = new MyValue();
161 for (int i = 0; i < 20_000; i++) {
162 testInvokeStatic( NON_BLOCKING_WARMUP, val);
163 testInvokeStaticNative(NON_BLOCKING_WARMUP, val);
164 testInvokeStaticSync( NON_BLOCKING_WARMUP, val);
165 testGetStatic( NON_BLOCKING_WARMUP, val);
166 testPutStatic( NON_BLOCKING_WARMUP, val);
167 testNewInstanceA( NON_BLOCKING_WARMUP, val);
168 testNewInstanceB( NON_BLOCKING_WARMUP, val);
169
170 testGetField(new B(), NON_BLOCKING_WARMUP, val);
171 testPutField(new B(), NON_BLOCKING_WARMUP, val);
172 testInvokeVirtual(new B(), NON_BLOCKING_WARMUP, val);
173 }
174 }
175
176 static void run() {
177 execute(ExceptionInInitializerError.class, () -> triggerInitialization(A.class));
178 ensureFinished();
179 runTests(); // after initialization is over
180 }
181 }
182
183 // ============================================================================================================== //
184
185 static void execute(Class<? extends Throwable> expectedExceptionClass, Runnable action) {
186 try {
187 action.run();
188 if (THROW) throw failure("no exception thrown");
189 } catch (Throwable e) {
190 if (THROW) {
191 if (e.getClass() == expectedExceptionClass) {
192 // expected
193 } else {
194 String msg = String.format("unexpected exception thrown: expected %s, caught %s",
195 expectedExceptionClass.getName(), e);
196 throw failure(msg, e);
197 }
198 } else {
199 throw failure("no exception expected", e);
200 }
201 }
202 }
203
204 private static AssertionError failure(String msg) {
205 return new AssertionError(phase + ": " + msg);
206 }
207
208 private static AssertionError failure(String msg, Throwable e) {
209 return new AssertionError(phase + ": " + msg, e);
210 }
211
212 static final List<Thread> BLOCKED_THREADS = Collections.synchronizedList(new ArrayList<>());
213 static final Consumer<Thread> ON_BLOCK = BLOCKED_THREADS::add;
214
215 static final Map<Thread,Throwable> FAILED_THREADS = Collections.synchronizedMap(new HashMap<>());
216 static final Thread.UncaughtExceptionHandler ON_FAILURE = FAILED_THREADS::put;
217
218 private static void ensureBlocked() {
219 for (Thread thr : BLOCKED_THREADS) {
220 try {
221 thr.join(100);
222 if (!thr.isAlive()) {
223 dump(thr);
224 throw new AssertionError("not blocked");
225 }
226 } catch (InterruptedException e) {
227 throw new Error(e);
228 }
229 }
230 }
231
232
233 private static void ensureFinished() {
234 for (Thread thr : BLOCKED_THREADS) {
235 try {
236 thr.join(15_000);
237 } catch (InterruptedException e) {
238 throw new Error(e);
239 }
240 if (thr.isAlive()) {
241 dump(thr);
242 throw new AssertionError(thr + ": still blocked");
243 }
244 }
245 for (Thread thr : BLOCKED_THREADS) {
246 if (THROW) {
247 if (!FAILED_THREADS.containsKey(thr)) {
248 throw new AssertionError(thr + ": exception not thrown");
249 }
250
251 Throwable ex = FAILED_THREADS.get(thr);
252 if (ex.getClass() != NoClassDefFoundError.class) {
253 throw new AssertionError(thr + ": wrong exception thrown", ex);
254 }
255 } else {
256 if (FAILED_THREADS.containsKey(thr)) {
257 Throwable ex = FAILED_THREADS.get(thr);
258 throw new AssertionError(thr + ": exception thrown", ex);
259 }
260 }
261 }
262 if (THROW) {
263 Asserts.assertEquals(BLOCKING_COUNTER.get(), 0);
264 } else {
265 Asserts.assertEquals(BLOCKING_COUNTER.get(), BLOCKING_ACTIONS.get());
266 }
267
268 dumpInfo();
269 }
270
271 interface TestCase0 {
272 void run(Runnable runnable, MyValue val);
273 }
274
275 interface TestCase1<T> {
276 void run(T arg, Runnable runnable, MyValue val);
277 }
278
279 enum Phase { BEFORE_INIT, IN_PROGRESS, FINISHED, INIT_FAILURE }
280
281 static volatile Phase phase = Phase.BEFORE_INIT;
282
283 static void changePhase(Phase newPhase) {
284 dumpInfo();
285
286 Phase oldPhase = phase;
287 switch (oldPhase) {
288 case BEFORE_INIT:
289 Asserts.assertEquals(NON_BLOCKING_ACTIONS.get(), 0);
290 Asserts.assertEquals(NON_BLOCKING_COUNTER.get(), 0);
291
292 Asserts.assertEquals(BLOCKING_ACTIONS.get(), 0);
293 Asserts.assertEquals(BLOCKING_COUNTER.get(), 0);
294 break;
295 case IN_PROGRESS:
296 Asserts.assertEquals(NON_BLOCKING_COUNTER.get(), NON_BLOCKING_ACTIONS.get());
297
298 Asserts.assertEquals(BLOCKING_COUNTER.get(), 0);
299 break;
300 default: throw new Error("wrong phase transition " + oldPhase);
301 }
302 phase = newPhase;
303 }
304
305 static void dumpInfo() {
306 System.out.println("Phase: " + phase);
307 System.out.println("Non-blocking actions: " + NON_BLOCKING_COUNTER.get() + " / " + NON_BLOCKING_ACTIONS.get());
308 System.out.println("Blocking actions: " + BLOCKING_COUNTER.get() + " / " + BLOCKING_ACTIONS.get());
309 }
310
311 static final Runnable NON_BLOCKING_WARMUP = () -> {
312 if (phase != Phase.IN_PROGRESS) {
313 throw new AssertionError("NON_BLOCKING: wrong phase: " + phase);
314 }
315 };
316
317 static Runnable disposableAction(final Phase validPhase, final AtomicInteger invocationCounter, final AtomicInteger actionCounter) {
318 actionCounter.incrementAndGet();
319
320 final AtomicBoolean cnt = new AtomicBoolean(false);
321 return () -> {
322 if (cnt.getAndSet(true)) {
323 throw new Error("repeated invocation");
324 }
325 invocationCounter.incrementAndGet();
326 if (phase != validPhase) {
327 throw new AssertionError("NON_BLOCKING: wrong phase: " + phase);
328 }
329 };
330 }
331
332 @FunctionalInterface
333 interface Factory<V> {
334 V get();
335 }
336
337 static final AtomicInteger NON_BLOCKING_COUNTER = new AtomicInteger(0);
338 static final AtomicInteger NON_BLOCKING_ACTIONS = new AtomicInteger(0);
339 static final Factory<Runnable> NON_BLOCKING = () -> disposableAction(phase, NON_BLOCKING_COUNTER, NON_BLOCKING_ACTIONS);
340
341 static final AtomicInteger BLOCKING_COUNTER = new AtomicInteger(0);
342 static final AtomicInteger BLOCKING_ACTIONS = new AtomicInteger(0);
343 static final Factory<Runnable> BLOCKING = () -> disposableAction(Phase.FINISHED, BLOCKING_COUNTER, BLOCKING_ACTIONS);
344
345 static void checkBlockingAction(TestCase0 r) {
346 MyValue val = new MyValue();
347 switch (phase) {
348 case IN_PROGRESS: {
349 // Barrier during class initalization.
350 r.run(NON_BLOCKING.get(), val); // initializing thread
351 checkBlocked(ON_BLOCK, ON_FAILURE, r); // different thread
352 break;
353 }
354 case FINISHED: {
355 // No barrier after class initalization is over.
356 r.run(NON_BLOCKING.get(), val); // initializing thread
357 checkNotBlocked(r); // different thread
358 break;
359 }
360 case INIT_FAILURE: {
361 // Exception is thrown after class initialization failed.
362 TestCase0 test = (action, valarg) -> execute(NoClassDefFoundError.class, () -> r.run(action, valarg));
363
364 test.run(NON_BLOCKING.get(), val); // initializing thread
365 checkNotBlocked(test); // different thread
366 break;
367 }
368 default: throw new Error("wrong phase: " + phase);
369 }
370 }
371
372 static void checkNonBlockingAction(TestCase0 r) {
373 r.run(NON_BLOCKING.get(), new MyValue()); // initializing thread
374 checkNotBlocked(r); // different thread
375 }
376
377 static <T> void checkNonBlockingAction(T recv, TestCase1<T> r) {
378 r.run(recv, NON_BLOCKING.get(), new MyValue()); // initializing thread
379 checkNotBlocked((action, val) -> r.run(recv, action, val)); // different thread
380 }
381
382 static void checkFailingAction(TestCase0 r) {
383 r.run(NON_BLOCKING.get(), new MyValue()); // initializing thread
384 checkNotBlocked(r); // different thread
385 }
386
387 static void triggerInitialization(Class<?> cls) {
388 try {
389 Class<?> loadedClass = Class.forName(cls.getName(), true, cls.getClassLoader());
390 if (loadedClass != cls) {
391 throw new Error("wrong class");
392 }
393 } catch (ClassNotFoundException e) {
394 throw new Error(e);
395 }
396 }
397
398 static void checkBlocked(Consumer<Thread> onBlockHandler, Thread.UncaughtExceptionHandler onException, TestCase0 r) {
399 Thread thr = new Thread(() -> {
400 try {
401 r.run(BLOCKING.get(), new MyValue());
402 System.out.println("Thread " + Thread.currentThread() + ": Finished successfully");
403 } catch(Throwable e) {
404 System.out.println("Thread " + Thread.currentThread() + ": Exception thrown: " + e);
405 if (!THROW) {
406 e.printStackTrace();
407 }
408 throw e;
409 }
410 } );
411 thr.setUncaughtExceptionHandler(onException);
412
413 thr.start();
414 try {
415 thr.join(100);
416
417 dump(thr);
418 if (thr.isAlive()) {
419 onBlockHandler.accept(thr); // blocked
420 } else {
421 throw new AssertionError("not blocked");
422 }
423 } catch (InterruptedException e) {
424 throw new Error(e);
425 }
426 }
427
428 static void checkNotBlocked(TestCase0 r) {
429 final Thread thr = new Thread(() -> r.run(NON_BLOCKING.get(), new MyValue()));
430 final Throwable[] ex = new Throwable[1];
431 thr.setUncaughtExceptionHandler((t, e) -> {
432 if (thr != t) {
433 ex[0] = new Error("wrong thread: " + thr + " vs " + t);
434 } else {
435 ex[0] = e;
436 }
437 });
438
439 thr.start();
440 try {
441 thr.join(15_000);
442 if (thr.isAlive()) {
443 dump(thr);
444 throw new AssertionError("blocked");
445 }
446 } catch (InterruptedException e) {
447 throw new Error(e);
448 }
449
450 if (ex[0] != null) {
451 throw new AssertionError("no exception expected", ex[0]);
452 }
453 }
454
455 static void maybeThrow() {
456 if (THROW) {
457 changePhase(Phase.INIT_FAILURE);
458 throw new RuntimeException("failed class initialization");
459 }
460 }
461
462 private static void dump(Thread thr) {
463 System.out.println("Thread: " + thr);
464 System.out.println("Thread state: " + thr.getState());
465 if (thr.isAlive()) {
466 for (StackTraceElement frame : thr.getStackTrace()) {
467 System.out.println(frame);
468 }
469 } else {
470 if (FAILED_THREADS.containsKey(thr)) {
471 System.out.println("Failed with an exception: ");
472 FAILED_THREADS.get(thr).toString();
473 } else {
474 System.out.println("Finished successfully");
475 }
476 }
477 }
478
479 public static void main(String[] args) throws Exception {
480 Test.run();
481 System.out.println("TEST PASSED");
482 }
483 }