1 /*
2 * Copyright (c) 2014, 2017, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package jdk.internal.module;
27
28 import java.io.File;
29 import java.io.PrintStream;
30 import java.lang.module.Configuration;
31 import java.lang.module.ModuleDescriptor;
32 import java.lang.module.ModuleFinder;
33 import java.lang.module.ModuleReference;
34 import java.lang.module.ResolvedModule;
35 import java.lang.reflect.Layer;
36 import java.lang.reflect.Module;
37 import java.net.URI;
38 import java.nio.file.Path;
39 import java.nio.file.Paths;
40 import java.util.ArrayList;
41 import java.util.Collections;
42 import java.util.HashMap;
43 import java.util.HashSet;
44 import java.util.List;
45 import java.util.Map;
46 import java.util.Optional;
47 import java.util.Set;
48 import java.util.function.Function;
49 import java.util.stream.Stream;
50
51 import jdk.internal.loader.BootLoader;
52 import jdk.internal.loader.BuiltinClassLoader;
53 import jdk.internal.misc.SharedSecrets;
54 import jdk.internal.perf.PerfCounter;
55
56 /**
57 * Initializes/boots the module system.
58 *
59 * The {@link #boot() boot} method is called early in the startup to initialize
60 * the module system. In summary, the boot method creates a Configuration by
61 * resolving a set of module names specified via the launcher (or equivalent)
62 * -m and --add-modules options. The modules are located on a module path that
63 * is constructed from the upgrade module path, system modules, and application
64 * module path. The Configuration is instantiated as the boot Layer with each
65 * module in the the configuration defined to one of the built-in class loaders.
66 */
67
68 public final class ModuleBootstrap {
69 private ModuleBootstrap() { }
70
71 private static final String JAVA_BASE = "java.base";
72
73 private static final String JAVA_SE = "java.se";
74
75 // the token for "all default modules"
76 private static final String ALL_DEFAULT = "ALL-DEFAULT";
77
78 // the token for "all unnamed modules"
79 private static final String ALL_UNNAMED = "ALL-UNNAMED";
80
81 // the token for "all system modules"
82 private static final String ALL_SYSTEM = "ALL-SYSTEM";
83
84 // the token for "all modules on the module path"
85 private static final String ALL_MODULE_PATH = "ALL-MODULE-PATH";
86
87 // The ModulePatcher for the initial configuration
88 private static final ModulePatcher patcher = initModulePatcher();
89
90 // ModuleFinder for the initial configuration
91 private static ModuleFinder initialFinder;
92
93 /**
94 * Returns the ModulePatcher for the initial configuration.
95 */
96 public static ModulePatcher patcher() {
97 return patcher;
98 }
99
100 /**
101 * Returns the ModuleFinder for the initial configuration
102 */
103 public static ModuleFinder finder() {
104 assert initialFinder != null;
105 return initialFinder;
106 }
107
108 /**
109 * Initialize the module system, returning the boot Layer.
110 *
111 * @see java.lang.System#initPhase2()
112 */
113 public static Layer boot() {
114
115 long t0 = System.nanoTime();
116
117 // system modules (may be patched)
118 ModuleFinder systemModules = ModuleFinder.ofSystem();
119
120 PerfCounters.systemModulesTime.addElapsedTimeFrom(t0);
121
122
123 long t1 = System.nanoTime();
124
125 // Once we have the system modules then we define the base module to
126 // the VM. We do this here so that java.base is defined as early as
127 // possible and also that resources in the base module can be located
128 // for error messages that may happen from here on.
129 ModuleReference base = systemModules.find(JAVA_BASE).orElse(null);
130 if (base == null)
131 throw new InternalError(JAVA_BASE + " not found");
132 URI baseUri = base.location().orElse(null);
133 if (baseUri == null)
134 throw new InternalError(JAVA_BASE + " does not have a location");
135 BootLoader.loadModule(base);
136 Modules.defineModule(null, base.descriptor(), baseUri);
137
138 PerfCounters.defineBaseTime.addElapsedTimeFrom(t1);
139
140
141 long t2 = System.nanoTime();
142
143 // --upgrade-module-path option specified to launcher
144 ModuleFinder upgradeModulePath
145 = createModulePathFinder("jdk.module.upgrade.path");
146 if (upgradeModulePath != null)
147 systemModules = ModuleFinder.compose(upgradeModulePath, systemModules);
148
149 // --module-path option specified to the launcher
150 ModuleFinder appModulePath = createModulePathFinder("jdk.module.path");
151
152 // The module finder: [--upgrade-module-path] system [--module-path]
153 ModuleFinder finder = systemModules;
154 if (appModulePath != null)
155 finder = ModuleFinder.compose(finder, appModulePath);
156
157 // The root modules to resolve
158 Set<String> roots = new HashSet<>();
159
160 // launcher -m option to specify the main/initial module
161 String mainModule = System.getProperty("jdk.module.main");
162 if (mainModule != null)
163 roots.add(mainModule);
164
165 // additional module(s) specified by --add-modules
166 boolean addAllDefaultModules = false;
167 boolean addAllSystemModules = false;
168 boolean addAllApplicationModules = false;
169 for (String mod: getExtraAddModules()) {
170 switch (mod) {
171 case ALL_DEFAULT:
172 addAllDefaultModules = true;
173 break;
174 case ALL_SYSTEM:
175 addAllSystemModules = true;
176 break;
177 case ALL_MODULE_PATH:
178 addAllApplicationModules = true;
179 break;
180 default :
181 roots.add(mod);
182 }
183 }
184
185 // --limit-modules
186 String propValue = getAndRemoveProperty("jdk.module.limitmods");
187 if (propValue != null) {
188 Set<String> mods = new HashSet<>();
189 for (String mod: propValue.split(",")) {
190 mods.add(mod);
191 }
192 finder = limitFinder(finder, mods, roots);
193 }
194
195 // If there is no initial module specified then assume that the initial
196 // module is the unnamed module of the application class loader. This
197 // is implemented by resolving "java.se" and all (non-java.*) modules
198 // that export an API. If "java.se" is not observable then all java.*
199 // modules are resolved. Modules that have the DO_NOT_RESOLVE_BY_DEFAULT
200 // bit set in their ModuleResolution attribute flags are excluded from
201 // the default set of roots.
202 if (mainModule == null || addAllDefaultModules) {
203 boolean hasJava = false;
204 if (systemModules.find(JAVA_SE).isPresent()) {
205 // java.se is a system module
206 if (finder == systemModules || finder.find(JAVA_SE).isPresent()) {
207 // java.se is observable
208 hasJava = true;
209 roots.add(JAVA_SE);
210 }
211 }
212
213 for (ModuleReference mref : systemModules.findAll()) {
214 String mn = mref.descriptor().name();
215 if (hasJava && mn.startsWith("java."))
216 continue;
217
218 if (ModuleResolution.doNotResolveByDefault(mref))
219 continue;
220
221 // add as root if observable and exports at least one package
222 if ((finder == systemModules || finder.find(mn).isPresent())) {
223 ModuleDescriptor descriptor = mref.descriptor();
224 for (ModuleDescriptor.Exports e : descriptor.exports()) {
225 if (!e.isQualified()) {
226 roots.add(mn);
227 break;
228 }
229 }
230 }
231 }
232 }
233
234 // If `--add-modules ALL-SYSTEM` is specified then all observable system
235 // modules will be resolved.
236 if (addAllSystemModules) {
237 ModuleFinder f = finder; // observable modules
238 systemModules.findAll()
239 .stream()
240 .filter(mref -> !ModuleResolution.doNotResolveByDefault(mref))
241 .map(ModuleReference::descriptor)
242 .map(ModuleDescriptor::name)
243 .filter(mn -> f.find(mn).isPresent()) // observable
244 .forEach(mn -> roots.add(mn));
245 }
246
247 // If `--add-modules ALL-MODULE-PATH` is specified then all observable
248 // modules on the application module path will be resolved.
249 if (appModulePath != null && addAllApplicationModules) {
250 ModuleFinder f = finder; // observable modules
251 appModulePath.findAll()
252 .stream()
253 .map(ModuleReference::descriptor)
254 .map(ModuleDescriptor::name)
255 .filter(mn -> f.find(mn).isPresent()) // observable
256 .forEach(mn -> roots.add(mn));
257 }
258
259 PerfCounters.optionsAndRootsTime.addElapsedTimeFrom(t2);
260
261
262 long t3 = System.nanoTime();
263
264 // determine if post resolution checks are needed
265 boolean needPostResolutionChecks = true;
266 if (baseUri.getScheme().equals("jrt") // toLowerCase not needed here
267 && (upgradeModulePath == null)
268 && (appModulePath == null)
269 && (patcher.isEmpty())) {
270 needPostResolutionChecks = false;
271 }
272
273 PrintStream traceOutput = null;
274 if (Boolean.getBoolean("jdk.launcher.traceResolver"))
275 traceOutput = System.out;
276
277 // run the resolver to create the configuration
278 Configuration cf = SharedSecrets.getJavaLangModuleAccess()
279 .resolveAndBind(finder,
280 roots,
281 needPostResolutionChecks,
282 traceOutput);
283
284 // time to create configuration
285 PerfCounters.resolveTime.addElapsedTimeFrom(t3);
286
287 // check module names and incubating status
288 checkModuleNamesAndStatus(cf);
289
290 // mapping of modules to class loaders
291 Function<String, ClassLoader> clf = ModuleLoaderMap.mappingFunction(cf);
292
293 // check that all modules to be mapped to the boot loader will be
294 // loaded from the runtime image
295 if (needPostResolutionChecks) {
296 for (ResolvedModule resolvedModule : cf.modules()) {
297 ModuleReference mref = resolvedModule.reference();
298 String name = mref.descriptor().name();
299 ClassLoader cl = clf.apply(name);
300 if (cl == null) {
301
302 if (upgradeModulePath != null
303 && upgradeModulePath.find(name).isPresent())
304 fail(name + ": cannot be loaded from upgrade module path");
305
306 if (!systemModules.find(name).isPresent())
307 fail(name + ": cannot be loaded from application module path");
308 }
309 }
310
311 // check if module specified in --patch-module is present
312 for (String mn: patcher.patchedModules()) {
313 if (!cf.findModule(mn).isPresent()) {
314 warnUnknownModule(PATCH_MODULE, mn);
315 }
316 }
317 }
318
319 // if needed check that there are no split packages in the set of
320 // resolved modules for the boot layer
321 if (SystemModules.hasSplitPackages() || needPostResolutionChecks) {
322 Map<String, String> packageToModule = new HashMap<>();
323 for (ResolvedModule resolvedModule : cf.modules()) {
324 ModuleDescriptor descriptor =
325 resolvedModule.reference().descriptor();
326 String name = descriptor.name();
327 for (String p : descriptor.packages()) {
328 String other = packageToModule.putIfAbsent(p, name);
329 if (other != null) {
330 fail("Package " + p + " in both module "
331 + name + " and module " + other);
332 }
333 }
334 }
335 }
336
337 long t4 = System.nanoTime();
338
339 // define modules to VM/runtime
340 Layer bootLayer = Layer.empty().defineModules(cf, clf);
341
342 PerfCounters.layerCreateTime.addElapsedTimeFrom(t4);
343
344
345 long t5 = System.nanoTime();
346
347 // define the module to its class loader, except java.base
348 for (ResolvedModule resolvedModule : cf.modules()) {
349 ModuleReference mref = resolvedModule.reference();
350 String name = mref.descriptor().name();
351 ClassLoader cl = clf.apply(name);
352 if (cl == null) {
353 if (!name.equals(JAVA_BASE)) BootLoader.loadModule(mref);
354 } else {
355 ((BuiltinClassLoader)cl).loadModule(mref);
356 }
357 }
358
359 PerfCounters.loadModulesTime.addElapsedTimeFrom(t5);
360
361
362 // --add-reads, -add-exports/-add-opens
363 addExtraReads(bootLayer);
364 addExtraExportsAndOpens(bootLayer);
365
366 // total time to initialize
367 PerfCounters.bootstrapTime.addElapsedTimeFrom(t0);
368
369 // remember the ModuleFinder
370 initialFinder = finder;
371
372 return bootLayer;
373 }
374
375 /**
376 * Returns a ModuleFinder that limits observability to the given root
377 * modules, their transitive dependences, plus a set of other modules.
378 */
379 private static ModuleFinder limitFinder(ModuleFinder finder,
380 Set<String> roots,
381 Set<String> otherMods)
382 {
383 // resolve all root modules
384 Configuration cf = Configuration.empty().resolve(finder,
385 ModuleFinder.of(),
386 roots);
387
388 // module name -> reference
389 Map<String, ModuleReference> map = new HashMap<>();
390
391 // root modules and their transitive dependences
392 cf.modules().stream()
393 .map(ResolvedModule::reference)
394 .forEach(mref -> map.put(mref.descriptor().name(), mref));
395
396 // additional modules
397 otherMods.stream()
398 .map(finder::find)
399 .flatMap(Optional::stream)
400 .forEach(mref -> map.putIfAbsent(mref.descriptor().name(), mref));
401
402 // set of modules that are observable
403 Set<ModuleReference> mrefs = new HashSet<>(map.values());
404
405 return new ModuleFinder() {
406 @Override
407 public Optional<ModuleReference> find(String name) {
408 return Optional.ofNullable(map.get(name));
409 }
410 @Override
411 public Set<ModuleReference> findAll() {
412 return mrefs;
413 }
414 };
415 }
416
417 /**
418 * Creates a finder from the module path that is the value of the given
419 * system property and optionally patched by --patch-module
420 */
421 private static ModuleFinder createModulePathFinder(String prop) {
422 String s = System.getProperty(prop);
423 if (s == null) {
424 return null;
425 } else {
426 String[] dirs = s.split(File.pathSeparator);
427 Path[] paths = new Path[dirs.length];
428 int i = 0;
429 for (String dir: dirs) {
430 paths[i++] = Paths.get(dir);
431 }
432 return ModulePath.of(patcher, paths);
433 }
434 }
435
436
437 /**
438 * Initialize the module patcher for the initial configuration passed on the
439 * value of the --patch-module options.
440 */
441 private static ModulePatcher initModulePatcher() {
442 Map<String, List<String>> map = decode("jdk.module.patch.",
443 File.pathSeparator,
444 false);
445 return new ModulePatcher(map);
446 }
447
448 /**
449 * Returns the set of module names specified via --add-modules options
450 * on the command line
451 */
452 private static Set<String> getExtraAddModules() {
453 String prefix = "jdk.module.addmods.";
454 int index = 0;
455
456 // the system property is removed after decoding
457 String value = getAndRemoveProperty(prefix + index);
458 if (value == null) {
459 return Collections.emptySet();
460 }
461
462 Set<String> modules = new HashSet<>();
463 while (value != null) {
464 for (String s : value.split(",")) {
465 if (s.length() > 0) modules.add(s);
466 }
467 index++;
468 value = getAndRemoveProperty(prefix + index);
469 }
470
471 return modules;
472 }
473
474 /**
475 * Process the --add-reads options to add any additional read edges that
476 * are specified on the command-line.
477 */
478 private static void addExtraReads(Layer bootLayer) {
479
480 // decode the command line options
481 Map<String, List<String>> map = decode("jdk.module.addreads.");
482 if (map.isEmpty())
483 return;
484
485 for (Map.Entry<String, List<String>> e : map.entrySet()) {
486
487 // the key is $MODULE
488 String mn = e.getKey();
489 Optional<Module> om = bootLayer.findModule(mn);
490 if (!om.isPresent()) {
491 warnUnknownModule(ADD_READS, mn);
492 continue;
493 }
494 Module m = om.get();
495
496 // the value is the set of other modules (by name)
497 for (String name : e.getValue()) {
498 if (ALL_UNNAMED.equals(name)) {
499 Modules.addReadsAllUnnamed(m);
500 } else {
501 om = bootLayer.findModule(name);
502 if (om.isPresent()) {
503 Modules.addReads(m, om.get());
504 } else {
505 warnUnknownModule(ADD_READS, name);
506 }
507 }
508 }
509 }
510 }
511
512 /**
513 * Process the --add-exports and --add-opens options to export/open
514 * additional packages specified on the command-line.
515 */
516 private static void addExtraExportsAndOpens(Layer bootLayer) {
517
518 // --add-exports
519 String prefix = "jdk.module.addexports.";
520 Map<String, List<String>> extraExports = decode(prefix);
521 if (!extraExports.isEmpty()) {
522 addExtraExportsOrOpens(bootLayer, extraExports, false);
523 }
524
525 // --add-opens
526 prefix = "jdk.module.addopens.";
527 Map<String, List<String>> extraOpens = decode(prefix);
528 if (!extraOpens.isEmpty()) {
529 addExtraExportsOrOpens(bootLayer, extraOpens, true);
530 }
531
532 }
533
534 private static void addExtraExportsOrOpens(Layer bootLayer,
535 Map<String, List<String>> map,
536 boolean opens)
537 {
538 String option = opens ? ADD_OPENS : ADD_EXPORTS;
539 for (Map.Entry<String, List<String>> e : map.entrySet()) {
540
541 // the key is $MODULE/$PACKAGE
542 String key = e.getKey();
543 String[] s = key.split("/");
544 if (s.length != 2)
545 fail(unableToParse(option, "<module>/<package>", key));
546
547 String mn = s[0];
548 String pn = s[1];
549 if (mn.isEmpty() || pn.isEmpty())
550 fail(unableToParse(option, "<module>/<package>", key));
551
552 // The exporting module is in the boot layer
553 Module m;
554 Optional<Module> om = bootLayer.findModule(mn);
555 if (!om.isPresent()) {
556 warnUnknownModule(option, mn);
557 continue;
558 }
559
560 m = om.get();
561
562 if (!m.getDescriptor().packages().contains(pn)) {
563 warn("package " + pn + " not in " + mn);
564 continue;
565 }
566
567 // the value is the set of modules to export to (by name)
568 for (String name : e.getValue()) {
569 boolean allUnnamed = false;
570 Module other = null;
571 if (ALL_UNNAMED.equals(name)) {
572 allUnnamed = true;
573 } else {
574 om = bootLayer.findModule(name);
575 if (om.isPresent()) {
576 other = om.get();
577 } else {
578 warnUnknownModule(option, name);
579 continue;
580 }
581 }
582 if (allUnnamed) {
583 if (opens) {
584 Modules.addOpensToAllUnnamed(m, pn);
585 } else {
586 Modules.addExportsToAllUnnamed(m, pn);
587 }
588 } else {
589 if (opens) {
590 Modules.addOpens(m, pn, other);
591 } else {
592 Modules.addExports(m, pn, other);
593 }
594 }
595
596 }
597 }
598 }
599
600 /**
601 * Decodes the values of --add-reads, -add-exports, --add-opens or
602 * --patch-modules options that are encoded in system properties.
603 *
604 * @param prefix the system property prefix
605 * @praam regex the regex for splitting the RHS of the option value
606 */
607 private static Map<String, List<String>> decode(String prefix,
608 String regex,
609 boolean allowDuplicates) {
610 int index = 0;
611 // the system property is removed after decoding
612 String value = getAndRemoveProperty(prefix + index);
613 if (value == null)
614 return Collections.emptyMap();
615
616 Map<String, List<String>> map = new HashMap<>();
617
618 while (value != null) {
619
620 int pos = value.indexOf('=');
621 if (pos == -1)
622 fail(unableToParse(option(prefix), "<module>=<value>", value));
623 if (pos == 0)
624 fail(unableToParse(option(prefix), "<module>=<value>", value));
625
626 // key is <module> or <module>/<package>
627 String key = value.substring(0, pos);
628
629 String rhs = value.substring(pos+1);
630 if (rhs.isEmpty())
631 fail(unableToParse(option(prefix), "<module>=<value>", value));
632
633 // value is <module>(,<module>)* or <file>(<pathsep><file>)*
634 if (!allowDuplicates && map.containsKey(key))
635 fail(key + " specified more than once in " + option(prefix));
636 List<String> values = map.computeIfAbsent(key, k -> new ArrayList<>());
637 int ntargets = 0;
638 for (String s : rhs.split(regex)) {
639 if (s.length() > 0) {
640 values.add(s);
641 ntargets++;
642 }
643 }
644 if (ntargets == 0)
645 fail("Target must be specified: " + option(prefix) + " " + value);
646
647 index++;
648 value = getAndRemoveProperty(prefix + index);
649 }
650
651 return map;
652 }
653
654 /**
655 * Decodes the values of --add-reads, -add-exports or --add-opens
656 * which use the "," to separate the RHS of the option value.
657 */
658 private static Map<String, List<String>> decode(String prefix) {
659 return decode(prefix, ",", true);
660 }
661
662 /**
663 * Gets and remove the named system property
664 */
665 private static String getAndRemoveProperty(String key) {
666 return (String)System.getProperties().remove(key);
667 }
668
669 /**
670 * Checks the names and resolution bit of each module in the configuration,
671 * emitting warnings if needed.
672 */
673 private static void checkModuleNamesAndStatus(Configuration cf) {
674 String incubating = null;
675 for (ResolvedModule rm : cf.modules()) {
676 ModuleReference mref = rm.reference();
677 String mn = mref.descriptor().name();
678
679 // emit warning if module name ends with a non-Java letter
680 if (!Checks.hasLegalModuleNameLastCharacter(mn))
681 warn("Module name \"" + mn + "\" may soon be illegal");
682
683 // emit warning if the WARN_INCUBATING module resolution bit set
684 if (ModuleResolution.hasIncubatingWarning(mref)) {
685 if (incubating == null) {
686 incubating = mn;
687 } else {
688 incubating += ", " + mn;
689 }
690 }
691 }
692 if (incubating != null)
693 warn("Using incubator modules: " + incubating);
694 }
695
696 /**
697 * Throws a RuntimeException with the given message
698 */
699 static void fail(String m) {
700 throw new RuntimeException(m);
701 }
702
703 static void warn(String m) {
704 System.err.println("WARNING: " + m);
705 }
706
707 static void warnUnknownModule(String option, String mn) {
708 warn("Unknown module: " + mn + " specified in " + option);
709 }
710
711 static String unableToParse(String option, String text, String value) {
712 return "Unable to parse " + option + " " + text + ": " + value;
713 }
714
715 private static final String ADD_MODULES = "--add-modules";
716 private static final String ADD_EXPORTS = "--add-exports";
717 private static final String ADD_OPENS = "--add-opens";
718 private static final String ADD_READS = "--add-reads";
719 private static final String PATCH_MODULE = "--patch-module";
720
721
722 /*
723 * Returns the command-line option name corresponds to the specified
724 * system property prefix.
725 */
726 static String option(String prefix) {
727 switch (prefix) {
728 case "jdk.module.addexports.":
729 return ADD_EXPORTS;
730 case "jdk.module.addopens.":
731 return ADD_OPENS;
732 case "jdk.module.addreads.":
733 return ADD_READS;
734 case "jdk.module.patch.":
735 return PATCH_MODULE;
736 case "jdk.module.addmods.":
737 return ADD_MODULES;
738 default:
739 throw new IllegalArgumentException(prefix);
740 }
741 }
742
743 static class PerfCounters {
744
745 static PerfCounter systemModulesTime
746 = PerfCounter.newPerfCounter("jdk.module.bootstrap.systemModulesTime");
747 static PerfCounter defineBaseTime
748 = PerfCounter.newPerfCounter("jdk.module.bootstrap.defineBaseTime");
749 static PerfCounter optionsAndRootsTime
750 = PerfCounter.newPerfCounter("jdk.module.bootstrap.optionsAndRootsTime");
751 static PerfCounter resolveTime
752 = PerfCounter.newPerfCounter("jdk.module.bootstrap.resolveTime");
753 static PerfCounter layerCreateTime
754 = PerfCounter.newPerfCounter("jdk.module.bootstrap.layerCreateTime");
755 static PerfCounter loadModulesTime
756 = PerfCounter.newPerfCounter("jdk.module.bootstrap.loadModulesTime");
757 static PerfCounter bootstrapTime
758 = PerfCounter.newPerfCounter("jdk.module.bootstrap.totalTime");
759 }
760 }