1 /*
2 * Copyright (c) 1997, 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 #include "cds/aotClassLocation.hpp"
26 #include "cds/cds_globals.hpp"
27 #include "cds/cdsConfig.hpp"
28 #include "cds/dynamicArchive.hpp"
29 #include "cds/heapShared.hpp"
30 #include "classfile/classFileStream.hpp"
31 #include "classfile/classLoader.inline.hpp"
32 #include "classfile/classLoaderData.inline.hpp"
33 #include "classfile/classLoadInfo.hpp"
34 #include "classfile/javaClasses.hpp"
35 #include "classfile/klassFactory.hpp"
36 #include "classfile/moduleEntry.hpp"
37 #include "classfile/modules.hpp"
38 #include "classfile/packageEntry.hpp"
39 #include "classfile/symbolTable.hpp"
40 #include "classfile/systemDictionary.hpp"
41 #include "classfile/systemDictionaryShared.hpp"
42 #include "classfile/vmClasses.hpp"
43 #include "classfile/vmSymbols.hpp"
44 #include "compiler/compileBroker.hpp"
45 #include "cppstdlib/cstdlib.hpp"
46 #include "interpreter/bytecodeStream.hpp"
47 #include "interpreter/oopMapCache.hpp"
48 #include "jimage.hpp"
49 #include "jvm.h"
50 #include "logging/log.hpp"
51 #include "logging/logStream.hpp"
52 #include "logging/logTag.hpp"
53 #include "memory/allocation.inline.hpp"
54 #include "memory/oopFactory.hpp"
55 #include "memory/resourceArea.hpp"
56 #include "memory/universe.hpp"
57 #include "oops/instanceKlass.hpp"
58 #include "oops/instanceRefKlass.hpp"
59 #include "oops/klass.inline.hpp"
60 #include "oops/method.inline.hpp"
61 #include "oops/objArrayOop.inline.hpp"
62 #include "oops/oop.inline.hpp"
63 #include "oops/symbol.hpp"
64 #include "prims/jvm_misc.hpp"
65 #include "runtime/arguments.hpp"
66 #include "runtime/handles.inline.hpp"
67 #include "runtime/init.hpp"
68 #include "runtime/interfaceSupport.inline.hpp"
69 #include "runtime/java.hpp"
70 #include "runtime/javaCalls.hpp"
71 #include "runtime/os.hpp"
72 #include "runtime/perfData.hpp"
73 #include "runtime/timer.hpp"
74 #include "runtime/vm_version.hpp"
75 #include "services/management.hpp"
76 #include "services/threadService.hpp"
77 #include "utilities/checkedCast.hpp"
78 #include "utilities/classpathStream.hpp"
79 #include "utilities/events.hpp"
80 #include "utilities/macros.hpp"
81 #include "utilities/ostream.hpp"
82 #include "utilities/utf8.hpp"
83
84 #include <ctype.h>
85
86 // Entry point in java.dll for path canonicalization
87
88 typedef int (*canonicalize_fn_t)(const char *orig, char *out, int len);
89
90 static canonicalize_fn_t CanonicalizeEntry = nullptr;
91
92 // Entry points for jimage.dll for loading jimage file entries
93
94 static JImageOpen_t JImageOpen = nullptr;
95 static JImageClose_t JImageClose = nullptr;
96 static JImageFindResource_t JImageFindResource = nullptr;
97 static JImageGetResource_t JImageGetResource = nullptr;
98
99 // JImageFile pointer, or null if exploded JDK build.
100 static JImageFile* JImage_file = nullptr;
101
102 // PreviewMode status to control preview behaviour. JImage_file is unusable
103 // for normal lookup until (Preview_mode != PREVIEW_MODE_UNINITIALIZED).
104 enum PreviewMode {
105 PREVIEW_MODE_UNINITIALIZED = 0,
106 PREVIEW_MODE_DEFAULT = 1,
107 PREVIEW_MODE_ENABLE_PREVIEW = 2
108 };
109 static PreviewMode Preview_mode = PREVIEW_MODE_UNINITIALIZED;
110
111 // Globals
112
113 PerfCounter* ClassLoader::_perf_accumulated_time = nullptr;
114 PerfCounter* ClassLoader::_perf_classes_inited = nullptr;
115 PerfCounter* ClassLoader::_perf_class_init_time = nullptr;
116 PerfCounter* ClassLoader::_perf_class_init_selftime = nullptr;
117 PerfCounter* ClassLoader::_perf_classes_verified = nullptr;
118 PerfCounter* ClassLoader::_perf_class_verify_time = nullptr;
119 PerfCounter* ClassLoader::_perf_class_verify_selftime = nullptr;
120 PerfCounter* ClassLoader::_perf_classes_linked = nullptr;
121 PerfCounter* ClassLoader::_perf_class_link_time = nullptr;
122 PerfCounter* ClassLoader::_perf_class_link_selftime = nullptr;
123 PerfCounter* ClassLoader::_perf_shared_classload_time = nullptr;
124 PerfCounter* ClassLoader::_perf_sys_classload_time = nullptr;
125 PerfCounter* ClassLoader::_perf_app_classload_time = nullptr;
126 PerfCounter* ClassLoader::_perf_app_classload_selftime = nullptr;
127 PerfCounter* ClassLoader::_perf_app_classload_count = nullptr;
128 PerfCounter* ClassLoader::_perf_define_appclasses = nullptr;
129 PerfCounter* ClassLoader::_perf_define_appclass_time = nullptr;
130 PerfCounter* ClassLoader::_perf_define_appclass_selftime = nullptr;
131 PerfCounter* ClassLoader::_perf_app_classfile_bytes_read = nullptr;
132 PerfCounter* ClassLoader::_perf_sys_classfile_bytes_read = nullptr;
133 PerfCounter* ClassLoader::_perf_ik_link_methods_time = nullptr;
134 PerfCounter* ClassLoader::_perf_method_adapters_time = nullptr;
135 PerfCounter* ClassLoader::_perf_ik_link_methods_count = nullptr;
136 PerfCounter* ClassLoader::_perf_method_adapters_count = nullptr;
137 PerfCounter* ClassLoader::_unsafe_defineClassCallCounter = nullptr;
138 PerfCounter* ClassLoader::_perf_secondary_hash_time = nullptr;
139 PerfCounter* ClassLoader::_perf_change_wx_time = nullptr;
140
141 PerfCounter* ClassLoader::_perf_resolve_indy_time = nullptr;
142 PerfCounter* ClassLoader::_perf_resolve_invokehandle_time = nullptr;
143 PerfCounter* ClassLoader::_perf_resolve_mh_time = nullptr;
144 PerfCounter* ClassLoader::_perf_resolve_mt_time = nullptr;
145
146 PerfCounter* ClassLoader::_perf_resolve_indy_count = nullptr;
147 PerfCounter* ClassLoader::_perf_resolve_invokehandle_count = nullptr;
148 PerfCounter* ClassLoader::_perf_resolve_mh_count = nullptr;
149 PerfCounter* ClassLoader::_perf_resolve_mt_count = nullptr;
150
151 void ClassLoader::print_counters(outputStream *st) {
152 st->print_cr("ClassLoader:");
153 st->print_cr(" clinit: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", ClassLoader::class_init_time_ms(), ClassLoader::class_init_count());
154 st->print_cr(" link methods: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_ik_link_methods_time->get_value()) , _perf_ik_link_methods_count->get_value());
155 st->print_cr(" method adapters: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_method_adapters_time->get_value()) , _perf_method_adapters_count->get_value());
156 st->print_cr(" resolve...");
157 st->print_cr(" invokedynamic: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_indy_time->get_value()) , _perf_resolve_indy_count->get_value());
158 st->print_cr(" invokehandle: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_invokehandle_time->get_value()) , _perf_resolve_invokehandle_count->get_value());
159 st->print_cr(" CP_MethodHandle: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_mh_time->get_value()) , _perf_resolve_mh_count->get_value());
160 st->print_cr(" CP_MethodType: " JLONG_FORMAT "ms / " JLONG_FORMAT " events", Management::ticks_to_ms(_perf_resolve_mt_time->get_value()) , _perf_resolve_mt_count->get_value());
161 st->cr();
162 }
163
164 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = nullptr;
165 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = nullptr;
166 ClassPathImageEntry* ClassLoader::_jrt_entry = nullptr;
167
168 ClassPathEntry* volatile ClassLoader::_first_append_entry_list = nullptr;
169 ClassPathEntry* volatile ClassLoader::_last_append_entry = nullptr;
170
171 // helper routines
172 #if INCLUDE_CDS
173 static bool string_starts_with(const char* str, const char* str_to_find) {
174 size_t str_len = strlen(str);
175 size_t str_to_find_len = strlen(str_to_find);
176 if (str_to_find_len > str_len) {
177 return false;
178 }
179 return (strncmp(str, str_to_find, str_to_find_len) == 0);
180 }
181 #endif
182
183 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
184 size_t str_len = strlen(str);
185 size_t str_to_find_len = strlen(str_to_find);
186 if (str_to_find_len > str_len) {
187 return false;
188 }
189 return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
190 }
191
192 // Used to obtain the package name from a fully qualified class name.
193 Symbol* ClassLoader::package_from_class_name(const Symbol* name, bool* bad_class_name) {
194 if (name == nullptr) {
195 if (bad_class_name != nullptr) {
196 *bad_class_name = true;
197 }
198 return nullptr;
199 }
200
201 int utf_len = name->utf8_length();
202 const jbyte* base = (const jbyte*)name->base();
203 const jbyte* start = base;
204 const jbyte* end = UTF8::strrchr(start, utf_len, JVM_SIGNATURE_SLASH);
205 if (end == nullptr) {
206 return nullptr;
207 }
208 // Skip over '['s
209 if (*start == JVM_SIGNATURE_ARRAY) {
210 do {
211 start++;
212 } while (start < end && *start == JVM_SIGNATURE_ARRAY);
213
214 // Fully qualified class names should not contain a 'L'.
215 // Set bad_class_name to true to indicate that the package name
216 // could not be obtained due to an error condition.
217 // In this situation, is_same_class_package returns false.
218 if (*start == JVM_SIGNATURE_CLASS) {
219 if (bad_class_name != nullptr) {
220 *bad_class_name = true;
221 }
222 return nullptr;
223 }
224 }
225 // A class name could have just the slash character in the name,
226 // in which case start > end
227 if (start >= end) {
228 // No package name
229 if (bad_class_name != nullptr) {
230 *bad_class_name = true;
231 }
232 return nullptr;
233 }
234 return SymbolTable::new_symbol(name, pointer_delta_as_int(start, base), pointer_delta_as_int(end, base));
235 }
236
237 // --------------------------------
238 // The following jimage_xxx static functions encapsulate all JImage_file and Preview_mode access.
239 // This is done to make it easy to reason about the JImage file state (exists vs initialized etc.).
240
241 // Opens the named JImage file and sets the JImage file reference.
242 // Returns true if opening the JImage file was successful (see also jimage_exists()).
243 static bool jimage_open(const char* modules_path) {
244 // Currently 'error' is not set to anything useful, so ignore it here.
245 jint error;
246 JImage_file = (*JImageOpen)(modules_path, &error);
247 return JImage_file != nullptr;
248 }
249
250 // Closes and clears the JImage file reference (this will only be called during shutdown).
251 static void jimage_close() {
252 if (JImage_file != nullptr) {
253 (*JImageClose)(JImage_file);
254 JImage_file = nullptr;
255 }
256 }
257
258 // Returns whether a JImage file was opened (but NOT whether it was initialized yet).
259 static bool jimage_exists() {
260 return JImage_file != nullptr;
261 }
262
263 // Returns the JImage file reference (which may or may not be initialized).
264 static JImageFile* jimage_non_null() {
265 assert(jimage_exists(), "should have been opened by ClassLoader::lookup_vm_options "
266 "and remained throughout normal JVM lifetime");
267 return JImage_file;
268 }
269
270 // Returns true if jimage_init() has been called. Once the JImage file is initialized,
271 // jimage_is_preview_enabled() can be called to correctly determine the access mode.
272 static bool jimage_is_initialized() {
273 return jimage_exists() && Preview_mode != PREVIEW_MODE_UNINITIALIZED;
274 }
275
276 // Returns the access mode for an initialized JImage file (reflects --enable-preview).
277 static bool is_preview_enabled() {
278 return Preview_mode == PREVIEW_MODE_ENABLE_PREVIEW;
279 }
280
281 // Looks up the location of a named JImage resource. This "raw" lookup function allows
282 // the preview mode to be manually specified, so must not be accessible outside this
283 // class. ClassPathImageEntry manages all calls for resources after startup is complete.
284 static JImageLocationRef jimage_find_resource(const char* module_name,
285 const char* file_name,
286 bool is_preview,
287 jlong *size) {
288 return ((*JImageFindResource)(jimage_non_null(),
289 module_name,
290 file_name,
291 is_preview,
292 size));
293 }
294 // --------------------------------
295
296 // Given a fully qualified package name, find its defining package in the class loader's
297 // package entry table.
298 PackageEntry* ClassLoader::get_package_entry(Symbol* pkg_name, ClassLoaderData* loader_data) {
299 if (pkg_name == nullptr) {
300 return nullptr;
301 }
302 PackageEntryTable* pkgEntryTable = loader_data->packages();
303 return pkgEntryTable->lookup_only(pkg_name);
304 }
305
306 const char* ClassPathEntry::copy_path(const char* path) {
307 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
308 strcpy(copy, path);
309 return copy;
310 }
311
312 ClassPathDirEntry::~ClassPathDirEntry() {
313 FREE_C_HEAP_ARRAY(char, _dir);
314 }
315
316 ClassFileStream* ClassPathDirEntry::open_stream(JavaThread* current, const char* name) {
317 // construct full path name
318 assert((_dir != nullptr) && (name != nullptr), "sanity");
319 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
320 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(current, char, path_len);
321 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
322 assert(len == (int)(path_len - 1), "sanity");
323 // check if file exists
324 struct stat st;
325 if (os::stat(path, &st) == 0) {
326 // found file, open it
327 int file_handle = os::open(path, 0, 0);
328 if (file_handle != -1) {
329 // read contents into resource array
330 u1* buffer = NEW_RESOURCE_ARRAY_IN_THREAD(current, u1, st.st_size);
331 size_t num_read = ::read(file_handle, (char*) buffer, st.st_size);
332 // close file
333 ::close(file_handle);
334 // construct ClassFileStream
335 if (num_read == (size_t)st.st_size) {
336 if (UsePerfData) {
337 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
338 }
339 #ifdef ASSERT
340 // Freeing path is a no-op here as buffer prevents it from being reclaimed. But we keep it for
341 // debug builds so that we guard against use-after-free bugs.
342 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
343 #endif
344 // We don't verify the length of the classfile stream fits in an int, but this is the
345 // bootloader so we have control of this.
346 // Resource allocated
347 return new ClassFileStream(buffer,
348 checked_cast<int>(st.st_size),
349 _dir);
350 }
351 }
352 }
353 FREE_RESOURCE_ARRAY_IN_THREAD(current, char, path, path_len);
354 return nullptr;
355 }
356
357 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name) : ClassPathEntry() {
358 _zip = zip;
359 _zip_name = copy_path(zip_name);
360 }
361
362 ClassPathZipEntry::~ClassPathZipEntry() {
363 ZipLibrary::close(_zip);
364 FREE_C_HEAP_ARRAY(char, _zip_name);
365 }
366
367 bool ClassPathZipEntry::has_entry(JavaThread* current, const char* name) {
368 ThreadToNativeFromVM ttn(current);
369 // check whether zip archive contains name
370 jint name_len;
371 jint filesize;
372 jzentry* entry = ZipLibrary::find_entry(_zip, name, &filesize, &name_len);
373 if (entry == nullptr) {
374 return false;
375 } else {
376 ZipLibrary::free_entry(_zip, entry);
377 return true;
378 }
379 }
380
381 u1* ClassPathZipEntry::open_entry(JavaThread* current, const char* name, jint* filesize, bool nul_terminate) {
382 // enable call to C land
383 ThreadToNativeFromVM ttn(current);
384 // check whether zip archive contains name
385 jint name_len;
386 jzentry* entry = ZipLibrary::find_entry(_zip, name, filesize, &name_len);
387 if (entry == nullptr) return nullptr;
388 u1* buffer;
389 char name_buf[128];
390 char* filename;
391 if (name_len < 128) {
392 filename = name_buf;
393 } else {
394 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
395 }
396
397 // read contents into resource array
398 size_t size = (uint32_t)(*filesize);
399 if (nul_terminate) {
400 if (sizeof(size) == sizeof(uint32_t) && size == UINT_MAX) {
401 return nullptr; // 32-bit integer overflow will occur.
402 }
403 size++;
404 }
405 buffer = NEW_RESOURCE_ARRAY(u1, size);
406 if (!ZipLibrary::read_entry(_zip, entry, buffer, filename)) {
407 return nullptr;
408 }
409
410 // return result
411 if (nul_terminate) {
412 buffer[size - 1] = 0;
413 }
414 return buffer;
415 }
416
417 ClassFileStream* ClassPathZipEntry::open_stream(JavaThread* current, const char* name) {
418 jint filesize;
419 u1* buffer = open_entry(current, name, &filesize, false);
420 if (buffer == nullptr) {
421 return nullptr;
422 }
423 if (UsePerfData) {
424 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
425 }
426 // Resource allocated
427 return new ClassFileStream(buffer,
428 filesize,
429 _zip_name);
430 }
431
432 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = nullptr;)
433
434 void ClassPathImageEntry::close_jimage() {
435 jimage_close();
436 }
437
438 ClassPathImageEntry::ClassPathImageEntry(const char* name) :
439 ClassPathEntry() {
440 guarantee(jimage_is_initialized(), "jimage is not initialized");
441 guarantee(name != nullptr, "jimage file name is null");
442
443 assert(_singleton == nullptr, "VM supports only one jimage");
444 DEBUG_ONLY(_singleton = this);
445 size_t len = strlen(name) + 1;
446 _name = copy_path(name);
447 }
448
449 ClassFileStream* ClassPathImageEntry::open_stream(JavaThread* current, const char* name) {
450 return open_stream_for_loader(current, name, ClassLoaderData::the_null_class_loader_data());
451 }
452
453 // For a class in a named module, look it up in the jimage file using this syntax:
454 // /<module-name>/<package-name>/<base-class>
455 //
456 // Assumptions:
457 // 1. There are no unnamed modules in the jimage file.
458 // 2. A package is in at most one module in the jimage file.
459 //
460 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(JavaThread* current, const char* name, ClassLoaderData* loader_data) {
461 const bool is_preview = is_preview_enabled();
462
463 jlong size;
464 JImageLocationRef location = 0;
465
466 TempNewSymbol class_name = SymbolTable::new_symbol(name);
467 TempNewSymbol pkg_name = ClassLoader::package_from_class_name(class_name);
468
469 if (pkg_name != nullptr) {
470 if (!Universe::is_module_initialized()) {
471 location = jimage_find_resource(JAVA_BASE_NAME, name, is_preview, &size);
472 } else {
473 PackageEntry* package_entry = ClassLoader::get_package_entry(pkg_name, loader_data);
474 if (package_entry != nullptr) {
475 ResourceMark rm(current);
476 // Get the module name
477 ModuleEntry* module = package_entry->module();
478 assert(module != nullptr, "Boot classLoader package missing module");
479 assert(module->is_named(), "Boot classLoader package is in unnamed module");
480 const char* module_name = module->name()->as_C_string();
481 if (module_name != nullptr) {
482 location = jimage_find_resource(module_name, name, is_preview, &size);
483 }
484 }
485 }
486 }
487
488 if (location != 0) {
489 if (UsePerfData) {
490 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
491 }
492 char* data = NEW_RESOURCE_ARRAY(char, size);
493 (*JImageGetResource)(jimage_non_null(), location, data, size);
494 // Resource allocated
495 assert(this == ClassLoader::get_jrt_entry(), "must be");
496 return new ClassFileStream((u1*)data,
497 checked_cast<int>(size),
498 _name,
499 true); // from_boot_loader_modules_image
500 }
501
502 return nullptr;
503 }
504
505 bool ClassPathImageEntry::is_modules_image() const {
506 assert(this == _singleton, "VM supports a single jimage");
507 assert(this == ClassLoader::get_jrt_entry(), "must be used for jrt entry");
508 return true;
509 }
510
511 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
512 _module_name = module_name;
513 _module_first_entry = nullptr;
514 _module_last_entry = nullptr;
515 }
516
517 ModuleClassPathList::~ModuleClassPathList() {
518 // Clean out each ClassPathEntry on list
519 ClassPathEntry* e = _module_first_entry;
520 while (e != nullptr) {
521 ClassPathEntry* next_entry = e->next();
522 delete e;
523 e = next_entry;
524 }
525 }
526
527 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
528 if (new_entry != nullptr) {
529 if (_module_last_entry == nullptr) {
530 _module_first_entry = _module_last_entry = new_entry;
531 } else {
532 _module_last_entry->set_next(new_entry);
533 _module_last_entry = new_entry;
534 }
535 }
536 }
537
538 void ClassLoader::trace_class_path(const char* msg, const char* name) {
539 LogTarget(Info, class, path) lt;
540 if (lt.is_enabled()) {
541 LogStream ls(lt);
542 if (msg) {
543 ls.print("%s", msg);
544 }
545 if (name) {
546 if (strlen(name) < 256) {
547 ls.print("%s", name);
548 } else {
549 // For very long paths, we need to print each character separately,
550 // as print_cr() has a length limit
551 while (name[0] != '\0') {
552 ls.print("%c", name[0]);
553 name++;
554 }
555 }
556 }
557 ls.cr();
558 }
559 }
560
561 void ClassLoader::setup_bootstrap_search_path(JavaThread* current) {
562 const char* bootcp = Arguments::get_boot_class_path();
563 assert(bootcp != nullptr, "Boot class path must not be nullptr");
564 if (PrintSharedArchiveAndExit) {
565 // Don't print bootcp - this is the bootcp of this current VM process, not necessarily
566 // the same as the boot classpath of the shared archive.
567 } else {
568 trace_class_path("bootstrap loader class path=", bootcp);
569 }
570 setup_bootstrap_search_path_impl(current, bootcp);
571 }
572
573 void ClassLoader::close_jrt_image() {
574 // Not applicable for exploded builds
575 if (!ClassLoader::has_jrt_entry()) return;
576 _jrt_entry->close_jimage();
577 }
578
579 // Construct the array of module/path pairs as specified to --patch-module
580 // for the boot loader to search ahead of the jimage, if the class being
581 // loaded is defined to a module that has been specified to --patch-module.
582 void ClassLoader::setup_patch_mod_entries() {
583 JavaThread* current = JavaThread::current();
584 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
585 int num_of_entries = patch_mod_args->length();
586
587 // Set up the boot loader's _patch_mod_entries list
588 _patch_mod_entries = new (mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, mtModule);
589
590 for (int i = 0; i < num_of_entries; i++) {
591 const char* module_name = (patch_mod_args->at(i))->module_name();
592 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
593 assert(module_sym != nullptr, "Failed to obtain Symbol for module name");
594 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
595
596 char* class_path = (patch_mod_args->at(i))->path_string();
597 ResourceMark rm(current);
598 ClasspathStream cp_stream(class_path);
599
600 while (cp_stream.has_next()) {
601 const char* path = cp_stream.get_next();
602 struct stat st;
603 if (os::stat(path, &st) == 0) {
604 // File or directory found
605 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st);
606 // If the path specification is valid, enter it into this module's list
607 if (new_entry != nullptr) {
608 module_cpl->add_to_list(new_entry);
609 }
610 }
611 }
612
613 // Record the module into the list of --patch-module entries only if
614 // valid ClassPathEntrys have been created
615 if (module_cpl->module_first_entry() != nullptr) {
616 _patch_mod_entries->push(module_cpl);
617 }
618 }
619 }
620
621 // Determine whether the module has been patched via the command-line
622 // option --patch-module
623 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
624 if (_patch_mod_entries != nullptr && _patch_mod_entries->is_nonempty()) {
625 int table_len = _patch_mod_entries->length();
626 for (int i = 0; i < table_len; i++) {
627 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
628 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
629 return true;
630 }
631 }
632 }
633 return false;
634 }
635
636 // Set up the _jrt_entry if present and boot append path
637 void ClassLoader::setup_bootstrap_search_path_impl(JavaThread* current, const char *class_path) {
638 ResourceMark rm(current);
639 ClasspathStream cp_stream(class_path);
640 bool set_base_piece = true;
641
642 #if INCLUDE_CDS
643 if (CDSConfig::is_dumping_archive()) {
644 if (!Arguments::has_jimage()) {
645 vm_exit_during_initialization("CDS is not supported in exploded JDK build", nullptr);
646 }
647 }
648 #endif
649
650 while (cp_stream.has_next()) {
651 const char* path = cp_stream.get_next();
652
653 if (set_base_piece) {
654 // The first time through the bootstrap_search setup, it must be determined
655 // what the base or core piece of the boot loader search is. Either a java runtime
656 // image is present or this is an exploded module build situation.
657 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
658 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
659 struct stat st;
660 if (os::stat(path, &st) == 0) {
661 // Directory found
662 if (jimage_exists()) {
663 assert(Arguments::has_jimage(), "sanity check");
664 const char* canonical_path = get_canonical_path(path, current);
665 assert(canonical_path != nullptr, "canonical_path issue");
666
667 // Hand over lifecycle control of the JImage file to the _jrt_entry singleton
668 // (see ClassPathImageEntry::close_jimage). The image must be initialized by now.
669 _jrt_entry = new ClassPathImageEntry(canonical_path);
670 assert(_jrt_entry != nullptr && _jrt_entry->is_modules_image(), "No java runtime image present");
671 } // else it's an exploded build.
672 } else {
673 // If path does not exist, exit
674 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
675 }
676 set_base_piece = false;
677 } else {
678 // Every entry on the boot class path after the initial base piece,
679 // which is set by os::set_boot_path(), is considered an appended entry.
680 update_class_path_entry_list(current, path);
681 }
682 }
683 }
684
685 // Gets the exploded path for the named module. The memory for the path
686 // is allocated on the C heap if `c_heap` is true otherwise in the resource area.
687 static const char* get_exploded_module_path(const char* module_name, bool c_heap) {
688 const char *home = Arguments::get_java_home();
689 const char file_sep = os::file_separator()[0];
690 // 10 represents the length of "modules" (7) + 2 file separators + \0
691 size_t len = strlen(home) + strlen(module_name) + 10;
692 char *path = c_heap ? NEW_C_HEAP_ARRAY(char, len, mtModule) : NEW_RESOURCE_ARRAY(char, len);
693 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
694 return path;
695 }
696
697 // Gets a preview path for a given class path as a resource.
698 static const char* get_preview_path(const char* path) {
699 const char file_sep = os::file_separator()[0];
700 // 18 represents the length of "META-INF" (8) + "preview" (7) + 2 file separators + \0
701 size_t len = strlen(path) + 18;
702 char *preview_path = NEW_RESOURCE_ARRAY(char, len);
703 jio_snprintf(preview_path, len, "%s%cMETA-INF%cpreview", path, file_sep, file_sep);
704 return preview_path;
705 }
706
707 // During an exploded modules build, each module defined to the boot loader
708 // will be added to the ClassLoader::_exploded_entries array.
709 void ClassLoader::add_to_exploded_build_list(JavaThread* current, Symbol* module_sym) {
710 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
711 assert(_exploded_entries != nullptr, "_exploded_entries was not initialized");
712
713 // Find the module's symbol
714 ResourceMark rm(current);
715 const char *module_name = module_sym->as_C_string();
716 const char *path = get_exploded_module_path(module_name, false);
717
718 struct stat st;
719 if (os::stat(path, &st) == 0) {
720 // Directory found
721 ClassPathEntry* new_entry = create_class_path_entry(current, path, &st);
722 // If the path specification is valid, enter it into this module's list.
723 // There is no need to check for duplicate modules in the exploded entry list,
724 // since no two modules with the same name can be defined to the boot loader.
725 // This is checked at module definition time in Modules::define_module.
726 if (new_entry != nullptr) {
727 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
728 log_info(class, load)("path: %s", path);
729
730 // If we are in preview mode, attempt to add a preview entry *before* the
731 // new class path entry if a preview path exists.
732 if (is_preview_enabled()) {
733 const char* preview_path = get_preview_path(path);
734 if (os::stat(preview_path, &st) == 0) {
735 ClassPathEntry* preview_entry = create_class_path_entry(current, preview_path, &st);
736 if (preview_entry != nullptr) {
737 module_cpl->add_to_list(preview_entry);
738 log_info(class, load)("preview path: %s", preview_path);
739 }
740 }
741 }
742
743 module_cpl->add_to_list(new_entry);
744 {
745 MutexLocker ml(current, Module_lock);
746 _exploded_entries->push(module_cpl);
747 }
748 }
749 }
750 }
751
752 jzfile* ClassLoader::open_zip_file(const char* canonical_path, char** error_msg, JavaThread* thread) {
753 // enable call to C land
754 ThreadToNativeFromVM ttn(thread);
755 HandleMark hm(thread);
756 return ZipLibrary::open(canonical_path, error_msg);
757 }
758
759 ClassPathEntry* ClassLoader::create_class_path_entry(JavaThread* current,
760 const char *path, const struct stat* st) {
761 ClassPathEntry* new_entry = nullptr;
762 if ((st->st_mode & S_IFMT) == S_IFREG) {
763 ResourceMark rm(current);
764 // Regular file, should be a zip file
765 // Canonicalized filename
766 const char* canonical_path = get_canonical_path(path, current);
767 if (canonical_path == nullptr) {
768 return nullptr;
769 }
770 char* error_msg = nullptr;
771 jzfile* zip = open_zip_file(canonical_path, &error_msg, current);
772 if (zip != nullptr && error_msg == nullptr) {
773 new_entry = new ClassPathZipEntry(zip, path);
774 } else {
775 return nullptr;
776 }
777 log_info(class, path)("opened: %s", path);
778 log_info(class, load)("opened: %s", path);
779 } else {
780 // Directory
781 new_entry = new ClassPathDirEntry(path);
782 log_info(class, load)("path: %s", path);
783 }
784 return new_entry;
785 }
786
787
788 // Create a class path zip entry for a given path (return null if not found
789 // or zip/JAR file cannot be opened)
790 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path) {
791 // check for a regular file
792 struct stat st;
793 if (os::stat(path, &st) == 0) {
794 if ((st.st_mode & S_IFMT) == S_IFREG) {
795 JavaThread* thread = JavaThread::current();
796 ResourceMark rm(thread);
797 const char* canonical_path = get_canonical_path(path, thread);
798 if (canonical_path != nullptr) {
799 char* error_msg = nullptr;
800 jzfile* zip = open_zip_file(canonical_path, &error_msg, thread);
801 if (zip != nullptr && error_msg == nullptr) {
802 // create using canonical path
803 return new ClassPathZipEntry(zip, canonical_path);
804 }
805 }
806 }
807 }
808 return nullptr;
809 }
810
811 // The boot append entries are added with a lock, and read lock free.
812 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
813 if (new_entry != nullptr) {
814 MutexLocker ml(Bootclasspath_lock, Mutex::_no_safepoint_check_flag);
815 if (_last_append_entry == nullptr) {
816 _last_append_entry = new_entry;
817 assert(first_append_entry() == nullptr, "boot loader's append class path entry list not empty");
818 AtomicAccess::release_store(&_first_append_entry_list, new_entry);
819 } else {
820 _last_append_entry->set_next(new_entry);
821 _last_append_entry = new_entry;
822 }
823 }
824 }
825
826 // Returns true IFF the file/dir exists and the entry was successfully created.
827 bool ClassLoader::update_class_path_entry_list(JavaThread* current, const char *path) {
828 struct stat st;
829 if (os::stat(path, &st) == 0) {
830 // File or directory found
831 ClassPathEntry* new_entry = nullptr;
832 new_entry = create_class_path_entry(current, path, &st);
833 if (new_entry == nullptr) {
834 return false;
835 }
836
837 // Do not reorder the bootclasspath which would break get_system_package().
838 // Add new entry to linked list
839 add_to_boot_append_entries(new_entry);
840 return true;
841 } else {
842 return false;
843 }
844 }
845
846 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
847 ResourceMark rm;
848 int num_of_entries = module_list->length();
849 for (int i = 0; i < num_of_entries; i++) {
850 ClassPathEntry* e;
851 ModuleClassPathList* mpl = module_list->at(i);
852 tty->print("%s=", mpl->module_name()->as_C_string());
853 e = mpl->module_first_entry();
854 while (e != nullptr) {
855 tty->print("%s", e->name());
856 e = e->next();
857 if (e != nullptr) {
858 tty->print("%s", os::path_separator());
859 }
860 }
861 tty->print(" ;");
862 }
863 }
864
865 void ClassLoader::print_bootclasspath() {
866 ClassPathEntry* e;
867 tty->print("[bootclasspath= ");
868
869 // Print --patch-module module/path specifications first
870 if (_patch_mod_entries != nullptr) {
871 print_module_entry_table(_patch_mod_entries);
872 }
873
874 // [jimage | exploded modules build]
875 if (has_jrt_entry()) {
876 // Print the location of the java runtime image
877 tty->print("%s ;", _jrt_entry->name());
878 } else {
879 // Print exploded module build path specifications
880 if (_exploded_entries != nullptr) {
881 print_module_entry_table(_exploded_entries);
882 }
883 }
884
885 // appended entries
886 e = first_append_entry();
887 while (e != nullptr) {
888 tty->print("%s ;", e->name());
889 e = e->next();
890 }
891 tty->print_cr("]");
892 }
893
894 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
895 void* func = os::dll_lookup(lib, name);
896 if (func == nullptr) {
897 char msg[256] = "";
898 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
899 vm_exit_during_initialization(msg, path);
900 }
901 return func;
902 }
903
904 void ClassLoader::load_java_library() {
905 assert(CanonicalizeEntry == nullptr, "should not load java library twice");
906 if (is_vm_statically_linked()) {
907 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, os::lookup_function("JDK_Canonicalize"));
908 assert(CanonicalizeEntry != nullptr, "could not lookup JDK_Canonicalize");
909 return;
910 }
911
912 void *javalib_handle = os::native_java_library();
913 if (javalib_handle == nullptr) {
914 vm_exit_during_initialization("Unable to load java library", nullptr);
915 }
916
917 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", nullptr));
918 assert(CanonicalizeEntry != nullptr, "could not lookup JDK_Canonicalize in java library");
919 }
920
921 void ClassLoader::load_jimage_library() {
922 assert(JImageOpen == nullptr, "should not load jimage library twice");
923
924 if (is_vm_statically_linked()) {
925 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, os::lookup_function("JIMAGE_Open"));
926 JImageClose = CAST_TO_FN_PTR(JImageClose_t, os::lookup_function("JIMAGE_Close"));
927 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, os::lookup_function("JIMAGE_FindResource"));
928 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, os::lookup_function("JIMAGE_GetResource"));
929 assert(JImageOpen != nullptr && JImageClose != nullptr &&
930 JImageFindResource != nullptr && JImageGetResource != nullptr,
931 "could not lookup all jimage library functions");
932 return;
933 }
934
935 char path[JVM_MAXPATHLEN];
936 char ebuf[1024];
937 void* handle = nullptr;
938 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
939 handle = os::dll_load(path, ebuf, sizeof ebuf);
940 }
941 if (handle == nullptr) {
942 vm_exit_during_initialization("Unable to load jimage library", path);
943 }
944
945 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
946 JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
947 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
948 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
949 assert(JImageOpen != nullptr && JImageClose != nullptr &&
950 JImageFindResource != nullptr && JImageGetResource != nullptr,
951 "could not lookup all jimage library functions in jimage library");
952 }
953
954 int ClassLoader::crc32(int crc, const char* buf, int len) {
955 return ZipLibrary::crc32(crc, (const jbyte*)buf, len);
956 }
957
958 oop ClassLoader::get_system_package(const char* name, TRAPS) {
959 // Look up the name in the boot loader's package entry table.
960 if (name != nullptr) {
961 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
962 // Look for the package entry in the boot loader's package entry table.
963 PackageEntry* package =
964 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
965
966 // Return null if package does not exist or if no classes in that package
967 // have been loaded.
968 if (package != nullptr && package->has_loaded_class()) {
969 ModuleEntry* module = package->module();
970 if (module->location() != nullptr) {
971 ResourceMark rm(THREAD);
972 Handle ml = java_lang_String::create_from_str(
973 module->location()->as_C_string(), THREAD);
974 return ml();
975 }
976 // Return entry on boot loader class path.
977 Handle cph = java_lang_String::create_from_str(
978 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
979 return cph();
980 }
981 }
982 return nullptr;
983 }
984
985 refArrayOop ClassLoader::get_system_packages(TRAPS) {
986 ResourceMark rm(THREAD);
987 // List of pointers to PackageEntrys that have loaded classes.
988 PackageEntryTable* pe_table =
989 ClassLoaderData::the_null_class_loader_data()->packages();
990 GrowableArray<PackageEntry*>* loaded_class_pkgs = pe_table->get_system_packages();
991
992 // Allocate objArray and fill with java.lang.String
993 refArrayOop r = oopFactory::new_refArray(vmClasses::String_klass(),
994 loaded_class_pkgs->length(),
995 CHECK_NULL);
996 refArrayHandle result(THREAD, r);
997 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
998 PackageEntry* package_entry = loaded_class_pkgs->at(x);
999 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1000 result->obj_at_put(x, str());
1001 }
1002 return result();
1003 }
1004
1005 // caller needs ResourceMark
1006 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1007 int class_name_len) {
1008 assert(class_name != nullptr, "invariant");
1009 assert((int)strlen(class_name) == class_name_len, "invariant");
1010
1011 static const char class_suffix[] = ".class";
1012 size_t class_suffix_len = sizeof(class_suffix);
1013
1014 char* const file_name = NEW_RESOURCE_ARRAY(char,
1015 class_name_len +
1016 class_suffix_len); // includes term null
1017
1018 strncpy(file_name, class_name, class_name_len);
1019 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1020
1021 return file_name;
1022 }
1023
1024 static ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1025 const GrowableArray<ModuleClassPathList*>* const module_list) {
1026 int num_of_entries = module_list->length();
1027 const Symbol* class_module_name = mod_entry->name();
1028
1029 // Loop through all the modules in either the patch-module or exploded entries looking for module
1030 for (int i = 0; i < num_of_entries; i++) {
1031 ModuleClassPathList* module_cpl = module_list->at(i);
1032 Symbol* module_cpl_name = module_cpl->module_name();
1033
1034 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1035 // Class' module has been located.
1036 return module_cpl->module_first_entry();
1037 }
1038 }
1039 return nullptr;
1040 }
1041
1042
1043 // Search the module list for the class file stream based on the file name and java package
1044 ClassFileStream* ClassLoader::search_module_entries(JavaThread* current,
1045 const GrowableArray<ModuleClassPathList*>* const module_list,
1046 PackageEntry* pkg_entry, // Java package entry derived from the class name
1047 const char* const file_name) {
1048 ClassFileStream* stream = nullptr;
1049
1050 // Find the defining module in the boot loader's module entry table
1051 ModuleEntry* mod_entry = (pkg_entry != nullptr) ? pkg_entry->module() : nullptr;
1052
1053 // If the module system has not defined java.base yet, then
1054 // classes loaded are assumed to be defined to java.base.
1055 // When java.base is eventually defined by the module system,
1056 // all packages of classes that have been previously loaded
1057 // are verified in ModuleEntryTable::verify_javabase_packages().
1058 if (!Universe::is_module_initialized() &&
1059 !ModuleEntryTable::javabase_defined() &&
1060 mod_entry == nullptr) {
1061 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1062 }
1063
1064 // The module must be a named module
1065 ClassPathEntry* e = nullptr;
1066 if (mod_entry != nullptr && mod_entry->is_named()) {
1067 if (module_list == _exploded_entries) {
1068 // The exploded build entries can be added to at any time so a lock is
1069 // needed when searching them.
1070 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1071 MutexLocker ml(current, Module_lock);
1072 e = find_first_module_cpe(mod_entry, module_list);
1073 } else {
1074 e = find_first_module_cpe(mod_entry, module_list);
1075 }
1076 }
1077
1078 // Try to load the class from the module's ClassPathEntry list.
1079 while (e != nullptr) {
1080 stream = e->open_stream(current, file_name);
1081 // No context.check is required since CDS is not supported
1082 // for an exploded modules build or if --patch-module is specified.
1083 if (nullptr != stream) {
1084 return stream;
1085 }
1086 e = e->next();
1087 }
1088 // If the module was located, break out even if the class was not
1089 // located successfully from that module's ClassPathEntry list.
1090 // There will not be another valid entry for that module.
1091 return nullptr;
1092 }
1093
1094 // Called by the boot classloader to load classes
1095 InstanceKlass* ClassLoader::load_class(Symbol* name, PackageEntry* pkg_entry, bool search_append_only, TRAPS) {
1096 assert(name != nullptr, "invariant");
1097
1098 ResourceMark rm(THREAD);
1099 HandleMark hm(THREAD);
1100
1101 const char* const class_name = name->as_C_string();
1102
1103 EventMarkClassLoading m("Loading class %s", class_name);
1104
1105 const char* const file_name = file_name_for_class_name(class_name,
1106 name->utf8_length());
1107 assert(file_name != nullptr, "invariant");
1108
1109 // Lookup stream for parsing .class file
1110 ClassFileStream* stream = nullptr;
1111 s2 classpath_index = 0;
1112 ClassPathEntry* e = nullptr;
1113 bool is_patched = false;
1114
1115 // If search_append_only is true, boot loader visibility boundaries are
1116 // set to be _first_append_entry to the end. This includes:
1117 // [-Xbootclasspath/a]; [jvmti appended entries]
1118 //
1119 // If search_append_only is false, boot loader visibility boundaries are
1120 // set to be the --patch-module entries plus the base piece. This includes:
1121 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1122 //
1123
1124 // Load Attempt #1: --patch-module
1125 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1126 // attempt to load the class from those locations specific to the module.
1127 // Specifications to --patch-module can contain a partial number of classes
1128 // that are part of the overall module definition. So if a particular class is not
1129 // found within its module specification, the search should continue to Load Attempt #2.
1130 // Note: The --patch-module entries are never searched if the boot loader's
1131 // visibility boundary is limited to only searching the append entries.
1132 if (_patch_mod_entries != nullptr && !search_append_only) {
1133 // At CDS dump time, the --patch-module entries are ignored. That means a
1134 // class is still loaded from the runtime image even if it might
1135 // appear in the _patch_mod_entries. The runtime shared class visibility
1136 // check will determine if a shared class is visible based on the runtime
1137 // environment, including the runtime --patch-module setting.
1138 if (!Arguments::is_valhalla_enabled()) {
1139 // Dynamic dumping requires UseSharedSpaces to be enabled. Since --patch-module
1140 // is not supported with UseSharedSpaces, we can never come here during dynamic dumping.
1141 assert(!CDSConfig::is_dumping_archive(), "CDS doesn't support --patch-module during dumping");
1142 }
1143 if (Arguments::is_valhalla_enabled() || !CDSConfig::is_dumping_static_archive()) {
1144 stream = search_module_entries(THREAD, _patch_mod_entries, pkg_entry, file_name);
1145 if (stream != nullptr) {
1146 is_patched = true;
1147 }
1148 }
1149 }
1150
1151 // Load Attempt #2: [jimage | exploded build]
1152 if (!search_append_only && (nullptr == stream)) {
1153 if (has_jrt_entry()) {
1154 e = _jrt_entry;
1155 stream = _jrt_entry->open_stream(THREAD, file_name);
1156 } else {
1157 // Exploded build - attempt to locate class in its defining module's location.
1158 assert(_exploded_entries != nullptr, "No exploded build entries present");
1159 assert(!CDSConfig::is_dumping_archive(), "CDS dumping doesn't support exploded build");
1160 stream = search_module_entries(THREAD, _exploded_entries, pkg_entry, file_name);
1161 }
1162 }
1163
1164 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1165 if (search_append_only && (nullptr == stream)) {
1166 // For the boot loader append path search, the starting classpath_index
1167 // for the appended piece is always 1 to account for either the
1168 // _jrt_entry or the _exploded_entries.
1169 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1170 classpath_index = 1;
1171
1172 e = first_append_entry();
1173 while (e != nullptr) {
1174 stream = e->open_stream(THREAD, file_name);
1175 if (nullptr != stream) {
1176 break;
1177 }
1178 e = e->next();
1179 ++classpath_index;
1180 }
1181 }
1182
1183 if (nullptr == stream) {
1184 return nullptr;
1185 }
1186
1187 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1188 Handle protection_domain;
1189 ClassLoadInfo cl_info(protection_domain);
1190
1191 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1192 name,
1193 loader_data,
1194 cl_info,
1195 CHECK_NULL);
1196 result->set_classpath_index(classpath_index);
1197 if (is_patched) {
1198 result->set_shared_classpath_index(0);
1199 }
1200 return result;
1201 }
1202
1203 #if INCLUDE_CDS
1204 static const char* skip_uri_protocol(const char* source) {
1205 if (strncmp(source, "file:", 5) == 0) {
1206 // file: protocol path could start with file:/ or file:///
1207 // locate the char after all the forward slashes
1208 int offset = 5;
1209 while (*(source + offset) == '/') {
1210 offset++;
1211 }
1212 source += offset;
1213 // for non-windows platforms, move back one char as the path begins with a '/'
1214 #ifndef _WINDOWS
1215 source -= 1;
1216 #endif
1217 } else if (strncmp(source, "jrt:/", 5) == 0) {
1218 source += 5;
1219 }
1220 return source;
1221 }
1222
1223 static char decode_percent_encoded(const char *str, size_t& index) {
1224 if (str[index] == '%'
1225 && isxdigit(str[index + 1])
1226 && isxdigit(str[index + 2])) {
1227 char hex[3];
1228 hex[0] = str[index + 1];
1229 hex[1] = str[index + 2];
1230 hex[2] = '\0';
1231 index += 2;
1232 return (char) strtol(hex, nullptr, 16);
1233 }
1234 return str[index];
1235 }
1236
1237 char* ClassLoader::uri_to_path(const char* uri) {
1238 const size_t len = strlen(uri) + 1;
1239 char* path = NEW_RESOURCE_ARRAY(char, len);
1240
1241 uri = skip_uri_protocol(uri);
1242
1243 if (strncmp(uri, "//", 2) == 0) {
1244 // Skip the empty "authority" part
1245 uri += 2;
1246 }
1247
1248 #ifdef _WINDOWS
1249 if (uri[0] == '/') {
1250 // Absolute path name on Windows does not begin with a slash
1251 uri += 1;
1252 }
1253 #endif
1254
1255 size_t path_index = 0;
1256 for (size_t i = 0; i < strlen(uri); ++i) {
1257 char decoded = decode_percent_encoded(uri, i);
1258 path[path_index++] = decoded;
1259 }
1260 path[path_index] = '\0';
1261 return path;
1262 }
1263
1264 // Record the shared classpath index and loader type for classes loaded
1265 // by the builtin loaders at dump time.
1266 void ClassLoader::record_result(JavaThread* current, InstanceKlass* ik,
1267 const ClassFileStream* stream, bool redefined) {
1268 assert(CDSConfig::is_dumping_archive(), "sanity");
1269 assert(stream != nullptr, "sanity");
1270
1271 if (ik->is_hidden()) {
1272 record_hidden_class(ik);
1273 return;
1274 }
1275
1276 if (ik->shared_classpath_index() == 0 && ik->defined_by_boot_loader()) {
1277 return;
1278 }
1279
1280 oop loader = ik->class_loader();
1281 char* src = (char*)stream->source();
1282 if (src == nullptr) {
1283 ik->set_shared_classpath_index(-1); // unsupported location
1284 return;
1285 }
1286
1287 if (!SystemDictionaryShared::is_builtin_loader(ik->class_loader_data())) {
1288 // A class loaded by a user-defined classloader.
1289 assert(ik->shared_classpath_index() < 0, "not assigned yet");
1290 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1291 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1292 return;
1293 }
1294
1295 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1296
1297 ResourceMark rm(current);
1298 int classpath_index = -1;
1299 bool found_invalid = false;
1300
1301 PackageEntry* pkg_entry = ik->package();
1302
1303 if (!AOTClassLocationConfig::dumptime_is_ready()) {
1304 // The shared path table is set up after module system initialization.
1305 // The path table contains no entry before that. Any classes loaded prior
1306 // to the setup of the shared path table must be from the modules image.
1307 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1308 classpath_index = 0;
1309 } else {
1310 // Save the path from the file: protocol or the module name from the jrt: protocol
1311 // if no protocol prefix is found, path is the same as stream->source(). This path
1312 // must be valid since the class has been successfully parsed.
1313 const char* path = ClassLoader::uri_to_path(src);
1314 assert(path != nullptr, "sanity");
1315 AOTClassLocationConfig::dumptime_iterate([&] (AOTClassLocation* cl) {
1316 int i = cl->index();
1317 // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1318 // The class must be from the runtime modules image.
1319 if (cl->is_modules_image() && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1320 classpath_index = i;
1321 } else if (os::same_files(cl->path(), path)) {
1322 // If the path (from the class stream source) is the same as the shared
1323 // class or module path, then we have a match.
1324 // src may come from the App/Platform class loaders, which would canonicalize
1325 // the file name. We cannot use strcmp to check for equality against cs->path().
1326 // We must use os::same_files (which is faster than canonicalizing cs->path()).
1327
1328 // null pkg_entry and pkg_entry in an unnamed module implies the class
1329 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1330 // and jvmti appended entries.
1331 if ((pkg_entry == nullptr) || (pkg_entry->in_unnamed_module())) {
1332 // Ensure the index is within the -cp range before assigning
1333 // to the classpath_index.
1334 if (SystemDictionary::is_system_class_loader(loader) && cl->from_app_classpath()) {
1335 classpath_index = i;
1336 } else {
1337 if (cl->from_boot_classpath()) {
1338 if (loader != nullptr) {
1339 // Probably loaded by jdk/internal/loader/ClassLoaders$BootClassLoader. Don't archive
1340 // such classes.
1341 found_invalid = true;
1342 } else {
1343 classpath_index = i;
1344 }
1345 }
1346 }
1347 } else {
1348 // A class from a named module from the --module-path. Ensure the index is
1349 // within the --module-path range before assigning to the classpath_index.
1350 if ((pkg_entry != nullptr) && !(pkg_entry->in_unnamed_module()) && cl->from_module_path()) {
1351 classpath_index = i;
1352 }
1353 }
1354 }
1355 if (classpath_index >= 0 || found_invalid) {
1356 return false; // Break the AOTClassLocationConfig::dumptime_iterate() loop.
1357 } else {
1358 return true; // Keep iterating
1359 }
1360 });
1361 }
1362
1363 if (found_invalid) {
1364 assert(classpath_index == -1, "sanity");
1365 }
1366
1367 const char* const class_name = ik->name()->as_C_string();
1368 const char* const file_name = file_name_for_class_name(class_name,
1369 ik->name()->utf8_length());
1370 assert(file_name != nullptr, "invariant");
1371 record_result_for_builtin_loader(checked_cast<s2>(classpath_index), ik, redefined);
1372 }
1373
1374 void ClassLoader::record_result_for_builtin_loader(s2 classpath_index, InstanceKlass* result, bool redefined) {
1375 assert(CDSConfig::is_dumping_archive(), "sanity");
1376
1377 oop loader = result->class_loader();
1378 if (SystemDictionary::is_system_class_loader(loader)) {
1379 AOTClassLocationConfig::dumptime_set_has_app_classes();
1380 } else if (SystemDictionary::is_platform_class_loader(loader)) {
1381 AOTClassLocationConfig::dumptime_set_has_platform_classes();
1382 } else {
1383 precond(loader == nullptr);
1384 }
1385
1386 if (CDSConfig::is_dumping_preimage_static_archive() || CDSConfig::is_dumping_dynamic_archive()) {
1387 if (!AOTClassLocationConfig::dumptime()->is_valid_classpath_index(classpath_index, result)) {
1388 classpath_index = -1;
1389 }
1390 }
1391
1392 AOTClassLocationConfig::dumptime_update_max_used_index(classpath_index);
1393 result->set_shared_classpath_index(classpath_index);
1394 }
1395
1396 void ClassLoader::record_hidden_class(InstanceKlass* ik) {
1397 assert(ik->is_hidden(), "must be");
1398
1399 if (ik->defined_by_other_loaders()) {
1400 // We don't archive hidden classes for non-builtin loaders.
1401 return;
1402 }
1403
1404 if (HeapShared::is_lambda_proxy_klass(ik)) {
1405 InstanceKlass* nest_host = ik->nest_host_not_null();
1406 ik->set_shared_classpath_index(nest_host->shared_classpath_index());
1407 } else if (HeapShared::is_lambda_form_klass(ik)) {
1408 ik->set_shared_classpath_index(0);
1409 } else {
1410 // Generated invoker classes.
1411 if (ik->defined_by_app_loader()) {
1412 ik->set_shared_classpath_index(AOTClassLocationConfig::dumptime()->app_cp_start_index());
1413 } else {
1414 ik->set_shared_classpath_index(0);
1415 }
1416 }
1417 }
1418
1419 void ClassLoader::append_boot_classpath(ClassPathEntry* new_entry) {
1420 if (CDSConfig::is_using_archive()) {
1421 warning("Sharing is only supported for boot loader classes because bootstrap classpath has been appended");
1422 FileMapInfo::current_info()->set_has_platform_or_app_classes(false);
1423 if (DynamicArchive::is_mapped()) {
1424 FileMapInfo::dynamic_info()->set_has_platform_or_app_classes(false);
1425 }
1426 }
1427 add_to_boot_append_entries(new_entry);
1428 }
1429 #endif // INCLUDE_CDS
1430
1431 // Initialize the class loader's access to methods in libzip. Parse and
1432 // process the boot classpath into a list ClassPathEntry objects. Once
1433 // this list has been created, it must not change order (see class PackageInfo)
1434 // it can be appended to and is by jvmti.
1435
1436 void ClassLoader::initialize(TRAPS) {
1437 if (UsePerfData) {
1438 // jvmstat performance counters
1439 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1440 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1441 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1442 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1443 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1444 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1445 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1446 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1447 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1448 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1449
1450 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1451 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1452 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1453 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1454 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1455 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1456 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1457 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1458 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1459 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1460 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS, "unsafeDefineClassCalls");
1461 NEWPERFTICKCOUNTER(_perf_secondary_hash_time, SUN_CLS, "secondarySuperHashTime");
1462 NEWPERFTICKCOUNTER(_perf_change_wx_time, SUN_CLS, "changeWXTime");
1463
1464 if (log_is_enabled(Info, perf, class, link)) {
1465 NEWPERFTICKCOUNTER(_perf_ik_link_methods_time, SUN_CLS, "linkMethodsTime");
1466 NEWPERFTICKCOUNTER(_perf_method_adapters_time, SUN_CLS, "makeAdaptersTime");
1467 NEWPERFEVENTCOUNTER(_perf_ik_link_methods_count, SUN_CLS, "linkMethodsCount");
1468 NEWPERFEVENTCOUNTER(_perf_method_adapters_count, SUN_CLS, "makeAdaptersCount");
1469
1470 NEWPERFTICKCOUNTER(_perf_resolve_indy_time, SUN_CLS, "resolve_invokedynamic_time");
1471 NEWPERFTICKCOUNTER(_perf_resolve_invokehandle_time, SUN_CLS, "resolve_invokehandle_time");
1472 NEWPERFTICKCOUNTER(_perf_resolve_mh_time, SUN_CLS, "resolve_MethodHandle_time");
1473 NEWPERFTICKCOUNTER(_perf_resolve_mt_time, SUN_CLS, "resolve_MethodType_time");
1474
1475 NEWPERFEVENTCOUNTER(_perf_resolve_indy_count, SUN_CLS, "resolve_invokedynamic_count");
1476 NEWPERFEVENTCOUNTER(_perf_resolve_invokehandle_count, SUN_CLS, "resolve_invokehandle_count");
1477 NEWPERFEVENTCOUNTER(_perf_resolve_mh_count, SUN_CLS, "resolve_MethodHandle_count");
1478 NEWPERFEVENTCOUNTER(_perf_resolve_mt_count, SUN_CLS, "resolve_MethodType_count");
1479 }
1480 }
1481
1482 // lookup java library entry points
1483 load_java_library();
1484 // jimage library entry points are loaded below, in lookup_vm_options
1485 setup_bootstrap_search_path(THREAD);
1486 }
1487
1488 // Lookup VM options embedded in the modules jimage file
1489 char* ClassLoader::lookup_vm_options() {
1490 char modules_path[JVM_MAXPATHLEN];
1491 const char* fileSep = os::file_separator();
1492
1493 // Initialize jimage library entry points
1494 load_jimage_library();
1495
1496 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1497 if (jimage_open(modules_path)) {
1498 // Special case where we lookup the options string *before* set_preview_mode() is called.
1499 // Since VM arguments have not been parsed, and the ClassPathImageEntry singleton
1500 // has not been created yet, we access the JImage file directly in non-preview mode.
1501 jlong size;
1502 JImageLocationRef location =
1503 jimage_find_resource(JAVA_BASE_NAME, "jdk/internal/vm/options", /* is_preview */ false, &size);
1504 if (location != 0) {
1505 char *options = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1506 (*JImageGetResource)(jimage_non_null(), location, options, size);
1507 options[size] = '\0';
1508 return options;
1509 }
1510 }
1511 return nullptr;
1512 }
1513
1514 // Finishes initializing the JImageFile (if present) by setting the access mode.
1515 void ClassLoader::set_preview_mode(bool enable_preview) {
1516 assert(Preview_mode == PREVIEW_MODE_UNINITIALIZED, "set_preview_mode must not be called twice");
1517 Preview_mode = enable_preview ? PREVIEW_MODE_ENABLE_PREVIEW : PREVIEW_MODE_DEFAULT;
1518 }
1519
1520 bool ClassLoader::is_module_observable(const char* module_name) {
1521 assert(JImageOpen != nullptr, "jimage library should have been opened");
1522 if (!jimage_exists()) {
1523 struct stat st;
1524 const char *path = get_exploded_module_path(module_name, true);
1525 bool res = os::stat(path, &st) == 0;
1526 FREE_C_HEAP_ARRAY(char, path);
1527 return res;
1528 }
1529 // We don't expect preview mode (i.e. --enable-preview) to affect module visibility.
1530 jlong size;
1531 return jimage_find_resource(module_name, "module-info.class", /* is_preview */ false, &size) != 0;
1532 }
1533
1534 jlong ClassLoader::classloader_time_ms() {
1535 return UsePerfData ?
1536 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1537 }
1538
1539 jlong ClassLoader::class_init_count() {
1540 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1541 }
1542
1543 jlong ClassLoader::class_init_time_ms() {
1544 return UsePerfData ?
1545 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1546 }
1547
1548 jlong ClassLoader::class_verify_time_ms() {
1549 return UsePerfData ?
1550 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1551 }
1552
1553 jlong ClassLoader::class_link_count() {
1554 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1555 }
1556
1557 jlong ClassLoader::class_link_time_ms() {
1558 return UsePerfData ?
1559 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1560 }
1561
1562 int ClassLoader::compute_Object_vtable() {
1563 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1564 // code to determine actual value from file
1565 // Would be value '11' if finals were in vtable
1566 int JDK_1_2_Object_vtable_size = 5;
1567 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1568 }
1569
1570
1571 void classLoader_init1() {
1572 EXCEPTION_MARK;
1573 ClassLoader::initialize(THREAD);
1574 if (HAS_PENDING_EXCEPTION) {
1575 vm_exit_during_initialization("ClassLoader::initialize() failed unexpectedly");
1576 }
1577 }
1578
1579 // Complete the ClassPathEntry setup for the boot loader
1580 void ClassLoader::classLoader_init2(JavaThread* current) {
1581 // Setup the list of module/path pairs for --patch-module processing
1582 // This must be done after the SymbolTable is created in order
1583 // to use fast_compare on module names instead of a string compare.
1584 if (Arguments::get_patch_mod_prefix() != nullptr) {
1585 setup_patch_mod_entries();
1586 }
1587
1588 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1589 // to successfully determine if java.base has been patched)
1590 create_javabase();
1591
1592 // Setup the initial java.base/path pair for the exploded build entries.
1593 // As more modules are defined during module system initialization, more
1594 // entries will be added to the exploded build array.
1595 if (!has_jrt_entry()) {
1596 assert(!CDSConfig::is_dumping_archive(), "not supported with exploded module builds");
1597 assert(!CDSConfig::is_using_archive(), "UsedSharedSpaces not supported with exploded module builds");
1598 // Set up the boot loader's _exploded_entries list. Note that this gets
1599 // done before loading any classes, by the same thread that will
1600 // subsequently do the first class load. So, no lock is needed for this.
1601 assert(_exploded_entries == nullptr, "Should only get initialized once");
1602 _exploded_entries = new (mtModule)
1603 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, mtModule);
1604 add_to_exploded_build_list(current, vmSymbols::java_base());
1605 }
1606 }
1607
1608 char* ClassLoader::get_canonical_path(const char* orig, Thread* thread) {
1609 assert(orig != nullptr, "bad arguments");
1610 // caller needs to allocate ResourceMark for the following output buffer
1611 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
1612 ResourceMark rm(thread);
1613 // os::native_path writes into orig_copy
1614 char* orig_copy = ResourceArea::strdup(thread, orig);
1615 if ((CanonicalizeEntry)(os::native_path(orig_copy), canonical_path, JVM_MAXPATHLEN) < 0) {
1616 return nullptr;
1617 }
1618 return canonical_path;
1619 }
1620
1621 void ClassLoader::create_javabase() {
1622 JavaThread* current = JavaThread::current();
1623
1624 // Create java.base's module entry for the boot
1625 // class loader prior to loading j.l.Object.
1626 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1627
1628 // Get module entry table
1629 ModuleEntryTable* null_cld_modules = null_cld->modules();
1630 if (null_cld_modules == nullptr) {
1631 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1632 }
1633
1634 {
1635 MutexLocker ml(current, Module_lock);
1636 if (ModuleEntryTable::javabase_moduleEntry() == nullptr) { // may have been inited by CDS.
1637 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1638 false, vmSymbols::java_base(), nullptr, nullptr, null_cld);
1639 if (jb_module == nullptr) {
1640 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1641 }
1642 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1643 }
1644 }
1645 }
1646
1647 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1648 // they could get inlined by aggressive compiler, an unknown trick, see bug 6966589.
1649 void PerfClassTraceTime::initialize() {
1650 if (!UsePerfData) return;
1651
1652 if (_eventp != nullptr) {
1653 // increment the event counter
1654 _eventp->inc();
1655 }
1656
1657 // stop the current active thread-local timer to measure inclusive time
1658 _prev_active_event = -1;
1659 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1660 if (_timers[i].is_active()) {
1661 assert(_prev_active_event == -1, "should have only one active timer");
1662 _prev_active_event = i;
1663 _timers[i].stop();
1664 }
1665 }
1666
1667 if (_recursion_counters == nullptr || (_recursion_counters[_event_type])++ == 0) {
1668 // start the inclusive timer if not recursively called
1669 _t.start();
1670 }
1671
1672 // start thread-local timer of the given event type
1673 if (!_timers[_event_type].is_active()) {
1674 _timers[_event_type].start();
1675 }
1676 }
1677
1678 PerfClassTraceTime::~PerfClassTraceTime() {
1679 if (!UsePerfData) return;
1680
1681 // stop the thread-local timer as the event completes
1682 // and resume the thread-local timer of the event next on the stack
1683 _timers[_event_type].stop();
1684 jlong selftime = _timers[_event_type].ticks();
1685
1686 if (_prev_active_event >= 0) {
1687 _timers[_prev_active_event].start();
1688 }
1689
1690 if (_recursion_counters != nullptr && --(_recursion_counters[_event_type]) > 0) return;
1691
1692 // increment the counters only on the leaf call
1693 _t.stop();
1694 _timep->inc(_t.ticks());
1695 if (_selftimep != nullptr) {
1696 _selftimep->inc(selftime);
1697 }
1698 // add all class loading related event selftime to the accumulated time counter
1699 ClassLoader::perf_accumulated_time()->inc(selftime);
1700
1701 // reset the timer
1702 _timers[_event_type].reset();
1703 }