1 /*
2 * Copyright (c) 1997, 2020, 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 "precompiled.hpp"
26 #include "jvm.h"
27 #include "jimage.hpp"
28 #include "classfile/classFileStream.hpp"
29 #include "classfile/classLoader.inline.hpp"
30 #include "classfile/classLoaderData.inline.hpp"
31 #include "classfile/classLoaderExt.hpp"
32 #include "classfile/javaClasses.hpp"
33 #include "classfile/moduleEntry.hpp"
34 #include "classfile/modules.hpp"
35 #include "classfile/packageEntry.hpp"
36 #include "classfile/klassFactory.hpp"
37 #include "classfile/symbolTable.hpp"
38 #include "classfile/systemDictionary.hpp"
39 #include "classfile/systemDictionaryShared.hpp"
40 #include "classfile/vmSymbols.hpp"
41 #include "compiler/compileBroker.hpp"
42 #include "interpreter/bytecodeStream.hpp"
43 #include "interpreter/oopMapCache.hpp"
44 #include "logging/log.hpp"
45 #include "logging/logStream.hpp"
46 #include "logging/logTag.hpp"
47 #include "memory/allocation.inline.hpp"
48 #include "memory/filemap.hpp"
49 #include "memory/oopFactory.hpp"
50 #include "memory/resourceArea.hpp"
51 #include "memory/universe.hpp"
52 #include "oops/instanceKlass.hpp"
53 #include "oops/instanceRefKlass.hpp"
54 #include "oops/method.inline.hpp"
55 #include "oops/objArrayOop.inline.hpp"
56 #include "oops/oop.inline.hpp"
57 #include "oops/symbol.hpp"
58 #include "prims/jvm_misc.hpp"
59 #include "runtime/arguments.hpp"
60 #include "runtime/handles.inline.hpp"
61 #include "runtime/init.hpp"
62 #include "runtime/interfaceSupport.inline.hpp"
63 #include "runtime/java.hpp"
64 #include "runtime/javaCalls.hpp"
65 #include "runtime/os.inline.hpp"
66 #include "runtime/threadCritical.hpp"
67 #include "runtime/timer.hpp"
68 #include "runtime/vm_version.hpp"
69 #include "services/management.hpp"
70 #include "services/threadService.hpp"
71 #include "utilities/classpathStream.hpp"
72 #include "utilities/events.hpp"
73 #include "utilities/hashtable.inline.hpp"
74 #include "utilities/macros.hpp"
75
76 // Entry point in java.dll for path canonicalization
77
78 typedef int (*canonicalize_fn_t)(const char *orig, char *out, int len);
79
80 static canonicalize_fn_t CanonicalizeEntry = NULL;
81
82 // Entry points in zip.dll for loading zip/jar file entries
83
84 typedef void * * (*ZipOpen_t)(const char *name, char **pmsg);
85 typedef void (*ZipClose_t)(jzfile *zip);
86 typedef jzentry* (*FindEntry_t)(jzfile *zip, const char *name, jint *sizeP, jint *nameLen);
87 typedef jboolean (*ReadEntry_t)(jzfile *zip, jzentry *entry, unsigned char *buf, char *namebuf);
88 typedef jzentry* (*GetNextEntry_t)(jzfile *zip, jint n);
89 typedef jint (*Crc32_t)(jint crc, const jbyte *buf, jint len);
90
91 static ZipOpen_t ZipOpen = NULL;
92 static ZipClose_t ZipClose = NULL;
93 static FindEntry_t FindEntry = NULL;
94 static ReadEntry_t ReadEntry = NULL;
95 static GetNextEntry_t GetNextEntry = NULL;
96 static Crc32_t Crc32 = NULL;
97
98 // Entry points for jimage.dll for loading jimage file entries
99
100 static JImageOpen_t JImageOpen = NULL;
101 static JImageClose_t JImageClose = NULL;
102 static JImagePackageToModule_t JImagePackageToModule = NULL;
103 static JImageFindResource_t JImageFindResource = NULL;
104 static JImageGetResource_t JImageGetResource = NULL;
105 static JImageResourceIterator_t JImageResourceIterator = NULL;
106
107 // Globals
108
109 PerfCounter* ClassLoader::_perf_accumulated_time = NULL;
110 PerfCounter* ClassLoader::_perf_classes_inited = NULL;
111 PerfCounter* ClassLoader::_perf_class_init_time = NULL;
112 PerfCounter* ClassLoader::_perf_class_init_selftime = NULL;
113 PerfCounter* ClassLoader::_perf_classes_verified = NULL;
114 PerfCounter* ClassLoader::_perf_class_verify_time = NULL;
115 PerfCounter* ClassLoader::_perf_class_verify_selftime = NULL;
116 PerfCounter* ClassLoader::_perf_classes_linked = NULL;
117 PerfCounter* ClassLoader::_perf_class_link_time = NULL;
118 PerfCounter* ClassLoader::_perf_class_link_selftime = NULL;
119 PerfCounter* ClassLoader::_perf_class_parse_time = NULL;
120 PerfCounter* ClassLoader::_perf_class_parse_selftime = NULL;
121 PerfCounter* ClassLoader::_perf_sys_class_lookup_time = NULL;
122 PerfCounter* ClassLoader::_perf_shared_classload_time = NULL;
123 PerfCounter* ClassLoader::_perf_sys_classload_time = NULL;
124 PerfCounter* ClassLoader::_perf_app_classload_time = NULL;
125 PerfCounter* ClassLoader::_perf_app_classload_selftime = NULL;
126 PerfCounter* ClassLoader::_perf_app_classload_count = NULL;
127 PerfCounter* ClassLoader::_perf_define_appclasses = NULL;
128 PerfCounter* ClassLoader::_perf_define_appclass_time = NULL;
129 PerfCounter* ClassLoader::_perf_define_appclass_selftime = NULL;
130 PerfCounter* ClassLoader::_perf_app_classfile_bytes_read = NULL;
131 PerfCounter* ClassLoader::_perf_sys_classfile_bytes_read = NULL;
132 PerfCounter* ClassLoader::_sync_systemLoaderLockContentionRate = NULL;
133 PerfCounter* ClassLoader::_sync_nonSystemLoaderLockContentionRate = NULL;
134 PerfCounter* ClassLoader::_sync_JVMFindLoadedClassLockFreeCounter = NULL;
135 PerfCounter* ClassLoader::_sync_JVMDefineClassLockFreeCounter = NULL;
136 PerfCounter* ClassLoader::_sync_JNIDefineClassLockFreeCounter = NULL;
137 PerfCounter* ClassLoader::_unsafe_defineClassCallCounter = NULL;
138
139 GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = NULL;
140 GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = NULL;
141 ClassPathEntry* ClassLoader::_jrt_entry = NULL;
142 ClassPathEntry* ClassLoader::_first_append_entry = NULL;
143 ClassPathEntry* ClassLoader::_last_append_entry = NULL;
144 #if INCLUDE_CDS
145 ClassPathEntry* ClassLoader::_app_classpath_entries = NULL;
146 ClassPathEntry* ClassLoader::_last_app_classpath_entry = NULL;
147 ClassPathEntry* ClassLoader::_module_path_entries = NULL;
148 ClassPathEntry* ClassLoader::_last_module_path_entry = NULL;
149 #endif
150
151 // helper routines
152 bool string_starts_with(const char* str, const char* str_to_find) {
153 size_t str_len = strlen(str);
154 size_t str_to_find_len = strlen(str_to_find);
155 if (str_to_find_len > str_len) {
156 return false;
157 }
158 return (strncmp(str, str_to_find, str_to_find_len) == 0);
159 }
160
161 static const char* get_jimage_version_string() {
162 static char version_string[10] = "";
163 if (version_string[0] == '\0') {
164 jio_snprintf(version_string, sizeof(version_string), "%d.%d",
165 VM_Version::vm_major_version(), VM_Version::vm_minor_version());
166 }
167 return (const char*)version_string;
168 }
169
170 bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
171 size_t str_len = strlen(str);
172 size_t str_to_find_len = strlen(str_to_find);
173 if (str_to_find_len > str_len) {
174 return false;
175 }
176 return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
177 }
178
179 // Used to obtain the package name from a fully qualified class name.
180 // It is the responsibility of the caller to establish a ResourceMark.
181 const char* ClassLoader::package_from_name(const char* const class_name, bool* bad_class_name) {
182 if (class_name == NULL) {
183 if (bad_class_name != NULL) {
184 *bad_class_name = true;
185 }
186 return NULL;
187 }
188
189 if (bad_class_name != NULL) {
190 *bad_class_name = false;
191 }
192
193 const char* const last_slash = strrchr(class_name, JVM_SIGNATURE_SLASH);
194 if (last_slash == NULL) {
195 // No package name
196 return NULL;
197 }
198
199 char* class_name_ptr = (char*) class_name;
200 // Skip over '['s
201 if (*class_name_ptr == JVM_SIGNATURE_ARRAY) {
202 do {
203 class_name_ptr++;
204 } while (*class_name_ptr == JVM_SIGNATURE_ARRAY);
205
206 // Fully qualified class names should not contain a 'L'.
207 // Set bad_class_name to true to indicate that the package name
208 // could not be obtained due to an error condition.
209 // In this situation, is_same_class_package returns false.
210 if (*class_name_ptr == JVM_SIGNATURE_CLASS) {
211 if (bad_class_name != NULL) {
212 *bad_class_name = true;
213 }
214 return NULL;
215 }
216 }
217
218 int length = last_slash - class_name_ptr;
219
220 // A class name could have just the slash character in the name.
221 if (length <= 0) {
222 // No package name
223 if (bad_class_name != NULL) {
224 *bad_class_name = true;
225 }
226 return NULL;
227 }
228
229 // drop name after last slash (including slash)
230 // Ex., "java/lang/String.class" => "java/lang"
231 char* pkg_name = NEW_RESOURCE_ARRAY(char, length + 1);
232 strncpy(pkg_name, class_name_ptr, length);
233 *(pkg_name+length) = '\0';
234
235 return (const char *)pkg_name;
236 }
237
238 // Given a fully qualified class name, find its defining package in the class loader's
239 // package entry table.
240 PackageEntry* ClassLoader::get_package_entry(const char* class_name, ClassLoaderData* loader_data, TRAPS) {
241 ResourceMark rm(THREAD);
242 const char *pkg_name = ClassLoader::package_from_name(class_name);
243 if (pkg_name == NULL) {
244 return NULL;
245 }
246 PackageEntryTable* pkgEntryTable = loader_data->packages();
247 TempNewSymbol pkg_symbol = SymbolTable::new_symbol(pkg_name);
248 return pkgEntryTable->lookup_only(pkg_symbol);
249 }
250
251 const char* ClassPathEntry::copy_path(const char* path) {
252 char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
253 strcpy(copy, path);
254 return copy;
255 }
256
257 ClassFileStream* ClassPathDirEntry::open_stream(const char* name, TRAPS) {
258 // construct full path name
259 assert((_dir != NULL) && (name != NULL), "sanity");
260 size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
261 char* path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, path_len);
262 int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
263 assert(len == (int)(path_len - 1), "sanity");
264 // check if file exists
265 struct stat st;
266 if (os::stat(path, &st) == 0) {
267 // found file, open it
268 int file_handle = os::open(path, 0, 0);
269 if (file_handle != -1) {
270 // read contents into resource array
271 u1* buffer = NEW_RESOURCE_ARRAY(u1, st.st_size);
272 size_t num_read = os::read(file_handle, (char*) buffer, st.st_size);
273 // close file
274 os::close(file_handle);
275 // construct ClassFileStream
276 if (num_read == (size_t)st.st_size) {
277 if (UsePerfData) {
278 ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
279 }
280 FREE_RESOURCE_ARRAY(char, path, path_len);
281 // Resource allocated
282 return new ClassFileStream(buffer,
283 st.st_size,
284 _dir,
285 ClassFileStream::verify);
286 }
287 }
288 }
289 FREE_RESOURCE_ARRAY(char, path, path_len);
290 return NULL;
291 }
292
293 ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name,
294 bool is_boot_append, bool from_class_path_attr) : ClassPathEntry() {
295 _zip = zip;
296 _zip_name = copy_path(zip_name);
297 _from_class_path_attr = from_class_path_attr;
298 }
299
300 ClassPathZipEntry::~ClassPathZipEntry() {
301 (*ZipClose)(_zip);
302 FREE_C_HEAP_ARRAY(char, _zip_name);
303 }
304
305 u1* ClassPathZipEntry::open_entry(const char* name, jint* filesize, bool nul_terminate, TRAPS) {
306 // enable call to C land
307 JavaThread* thread = JavaThread::current();
308 ThreadToNativeFromVM ttn(thread);
309 // check whether zip archive contains name
310 jint name_len;
311 jzentry* entry = (*FindEntry)(_zip, name, filesize, &name_len);
312 if (entry == NULL) return NULL;
313 u1* buffer;
314 char name_buf[128];
315 char* filename;
316 if (name_len < 128) {
317 filename = name_buf;
318 } else {
319 filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
320 }
321
322 // read contents into resource array
323 int size = (*filesize) + ((nul_terminate) ? 1 : 0);
324 buffer = NEW_RESOURCE_ARRAY(u1, size);
325 if (!(*ReadEntry)(_zip, entry, buffer, filename)) return NULL;
326
327 // return result
328 if (nul_terminate) {
329 buffer[*filesize] = 0;
330 }
331 return buffer;
332 }
333
334 ClassFileStream* ClassPathZipEntry::open_stream(const char* name, TRAPS) {
335 jint filesize;
336 u1* buffer = open_entry(name, &filesize, false, CHECK_NULL);
337 if (buffer == NULL) {
338 return NULL;
339 }
340 if (UsePerfData) {
341 ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
342 }
343 // Resource allocated
344 return new ClassFileStream(buffer,
345 filesize,
346 _zip_name,
347 ClassFileStream::verify);
348 }
349
350 // invoke function for each entry in the zip file
351 void ClassPathZipEntry::contents_do(void f(const char* name, void* context), void* context) {
352 JavaThread* thread = JavaThread::current();
353 HandleMark handle_mark(thread);
354 ThreadToNativeFromVM ttn(thread);
355 for (int n = 0; ; n++) {
356 jzentry * ze = ((*GetNextEntry)(_zip, n));
357 if (ze == NULL) break;
358 (*f)(ze->name, context);
359 }
360 }
361
362 DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = NULL;)
363
364 void ClassPathImageEntry::close_jimage() {
365 if (_jimage != NULL) {
366 (*JImageClose)(_jimage);
367 _jimage = NULL;
368 }
369 }
370
371 ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
372 ClassPathEntry(),
373 _jimage(jimage) {
374 guarantee(jimage != NULL, "jimage file is null");
375 guarantee(name != NULL, "jimage file name is null");
376 assert(_singleton == NULL, "VM supports only one jimage");
377 DEBUG_ONLY(_singleton = this);
378 size_t len = strlen(name) + 1;
379 _name = copy_path(name);
380 }
381
382 ClassPathImageEntry::~ClassPathImageEntry() {
383 assert(_singleton == this, "must be");
384 DEBUG_ONLY(_singleton = NULL);
385
386 FREE_C_HEAP_ARRAY(const char, _name);
387
388 if (_jimage != NULL) {
389 (*JImageClose)(_jimage);
390 _jimage = NULL;
391 }
392 }
393
394 ClassFileStream* ClassPathImageEntry::open_stream(const char* name, TRAPS) {
395 return open_stream_for_loader(name, ClassLoaderData::the_null_class_loader_data(), THREAD);
396 }
397
398 // For a class in a named module, look it up in the jimage file using this syntax:
399 // /<module-name>/<package-name>/<base-class>
400 //
401 // Assumptions:
402 // 1. There are no unnamed modules in the jimage file.
403 // 2. A package is in at most one module in the jimage file.
404 //
405 ClassFileStream* ClassPathImageEntry::open_stream_for_loader(const char* name, ClassLoaderData* loader_data, TRAPS) {
406 jlong size;
407 JImageLocationRef location = (*JImageFindResource)(_jimage, "", get_jimage_version_string(), name, &size);
408
409 if (location == 0) {
410 ResourceMark rm;
411 const char* pkg_name = ClassLoader::package_from_name(name);
412
413 if (pkg_name != NULL) {
414 if (!Universe::is_module_initialized()) {
415 location = (*JImageFindResource)(_jimage, JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
416 } else {
417 PackageEntry* package_entry = ClassLoader::get_package_entry(name, loader_data, CHECK_NULL);
418 if (package_entry != NULL) {
419 ResourceMark rm;
420 // Get the module name
421 ModuleEntry* module = package_entry->module();
422 assert(module != NULL, "Boot classLoader package missing module");
423 assert(module->is_named(), "Boot classLoader package is in unnamed module");
424 const char* module_name = module->name()->as_C_string();
425 if (module_name != NULL) {
426 location = (*JImageFindResource)(_jimage, module_name, get_jimage_version_string(), name, &size);
427 }
428 }
429 }
430 }
431 }
432 if (location != 0) {
433 if (UsePerfData) {
434 ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
435 }
436 char* data = NEW_RESOURCE_ARRAY(char, size);
437 (*JImageGetResource)(_jimage, location, data, size);
438 // Resource allocated
439 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
440 return new ClassFileStream((u1*)data,
441 (int)size,
442 _name,
443 ClassFileStream::verify,
444 true); // from_boot_loader_modules_image
445 }
446
447 return NULL;
448 }
449
450 JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
451 const char* module_name,
452 const char* file_name,
453 jlong &size) {
454 return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
455 }
456
457 bool ClassPathImageEntry::is_modules_image() const {
458 assert(this == _singleton, "VM supports a single jimage");
459 assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
460 return true;
461 }
462
463 #if INCLUDE_CDS
464 void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
465 Arguments::assert_is_dumping_archive();
466 tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
467 vm_exit_during_initialization(error, message);
468 }
469 #endif
470
471 ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
472 _module_name = module_name;
473 _module_first_entry = NULL;
474 _module_last_entry = NULL;
475 }
476
477 ModuleClassPathList::~ModuleClassPathList() {
478 // Clean out each ClassPathEntry on list
479 ClassPathEntry* e = _module_first_entry;
480 while (e != NULL) {
481 ClassPathEntry* next_entry = e->next();
482 delete e;
483 e = next_entry;
484 }
485 }
486
487 void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
488 if (new_entry != NULL) {
489 if (_module_last_entry == NULL) {
490 _module_first_entry = _module_last_entry = new_entry;
491 } else {
492 _module_last_entry->set_next(new_entry);
493 _module_last_entry = new_entry;
494 }
495 }
496 }
497
498 void ClassLoader::trace_class_path(const char* msg, const char* name) {
499 LogTarget(Info, class, path) lt;
500 if (lt.is_enabled()) {
501 LogStream ls(lt);
502 if (msg) {
503 ls.print("%s", msg);
504 }
505 if (name) {
506 if (strlen(name) < 256) {
507 ls.print("%s", name);
508 } else {
509 // For very long paths, we need to print each character separately,
510 // as print_cr() has a length limit
511 while (name[0] != '\0') {
512 ls.print("%c", name[0]);
513 name++;
514 }
515 }
516 }
517 ls.cr();
518 }
519 }
520
521 void ClassLoader::setup_bootstrap_search_path() {
522 const char* sys_class_path = Arguments::get_sysclasspath();
523 assert(sys_class_path != NULL, "System boot class path must not be NULL");
524 if (PrintSharedArchiveAndExit) {
525 // Don't print sys_class_path - this is the bootcp of this current VM process, not necessarily
526 // the same as the bootcp of the shared archive.
527 } else {
528 trace_class_path("bootstrap loader class path=", sys_class_path);
529 }
530 setup_boot_search_path(sys_class_path);
531 }
532
533 #if INCLUDE_CDS
534 void ClassLoader::setup_app_search_path(const char *class_path) {
535 Arguments::assert_is_dumping_archive();
536
537 ResourceMark rm;
538 ClasspathStream cp_stream(class_path);
539
540 while (cp_stream.has_next()) {
541 const char* path = cp_stream.get_next();
542 update_class_path_entry_list(path, false, false, false);
543 }
544 }
545
546 void ClassLoader::add_to_module_path_entries(const char* path,
547 ClassPathEntry* entry) {
548 assert(entry != NULL, "ClassPathEntry should not be NULL");
549 Arguments::assert_is_dumping_archive();
550
551 // The entry does not exist, add to the list
552 if (_module_path_entries == NULL) {
553 assert(_last_module_path_entry == NULL, "Sanity");
554 _module_path_entries = _last_module_path_entry = entry;
555 } else {
556 _last_module_path_entry->set_next(entry);
557 _last_module_path_entry = entry;
558 }
559 }
560
561 // Add a module path to the _module_path_entries list.
562 void ClassLoader::update_module_path_entry_list(const char *path, TRAPS) {
563 Arguments::assert_is_dumping_archive();
564 struct stat st;
565 if (os::stat(path, &st) != 0) {
566 tty->print_cr("os::stat error %d (%s). CDS dump aborted (path was \"%s\").",
567 errno, os::errno_name(errno), path);
568 vm_exit_during_initialization();
569 }
570 // File or directory found
571 ClassPathEntry* new_entry = NULL;
572 new_entry = create_class_path_entry(path, &st, true /* throw_exception */,
573 false /*is_boot_append */, false /* from_class_path_attr */, CHECK);
574 if (new_entry == NULL) {
575 return;
576 }
577
578 add_to_module_path_entries(path, new_entry);
579 return;
580 }
581
582 void ClassLoader::setup_module_search_path(const char* path, TRAPS) {
583 update_module_path_entry_list(path, THREAD);
584 }
585
586 #endif // INCLUDE_CDS
587
588 void ClassLoader::close_jrt_image() {
589 // Not applicable for exploded builds
590 if (!ClassLoader::has_jrt_entry()) return;
591 _jrt_entry->close_jimage();
592 }
593
594 // Construct the array of module/path pairs as specified to --patch-module
595 // for the boot loader to search ahead of the jimage, if the class being
596 // loaded is defined to a module that has been specified to --patch-module.
597 void ClassLoader::setup_patch_mod_entries() {
598 Thread* THREAD = Thread::current();
599 GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
600 int num_of_entries = patch_mod_args->length();
601
602 // Set up the boot loader's _patch_mod_entries list
603 _patch_mod_entries = new (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, true);
604
605 for (int i = 0; i < num_of_entries; i++) {
606 const char* module_name = (patch_mod_args->at(i))->module_name();
607 Symbol* const module_sym = SymbolTable::new_symbol(module_name);
608 assert(module_sym != NULL, "Failed to obtain Symbol for module name");
609 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
610
611 char* class_path = (patch_mod_args->at(i))->path_string();
612 ResourceMark rm(THREAD);
613 ClasspathStream cp_stream(class_path);
614
615 while (cp_stream.has_next()) {
616 const char* path = cp_stream.get_next();
617 struct stat st;
618 if (os::stat(path, &st) == 0) {
619 // File or directory found
620 ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
621 // If the path specification is valid, enter it into this module's list
622 if (new_entry != NULL) {
623 module_cpl->add_to_list(new_entry);
624 }
625 }
626 }
627
628 // Record the module into the list of --patch-module entries only if
629 // valid ClassPathEntrys have been created
630 if (module_cpl->module_first_entry() != NULL) {
631 _patch_mod_entries->push(module_cpl);
632 }
633 }
634 }
635
636 // Determine whether the module has been patched via the command-line
637 // option --patch-module
638 bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
639 if (_patch_mod_entries != NULL && _patch_mod_entries->is_nonempty()) {
640 int table_len = _patch_mod_entries->length();
641 for (int i = 0; i < table_len; i++) {
642 ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
643 if (module_name->fast_compare(patch_mod->module_name()) == 0) {
644 return true;
645 }
646 }
647 }
648 return false;
649 }
650
651 // Set up the _jrt_entry if present and boot append path
652 void ClassLoader::setup_boot_search_path(const char *class_path) {
653 EXCEPTION_MARK;
654 ResourceMark rm(THREAD);
655 ClasspathStream cp_stream(class_path);
656 bool set_base_piece = true;
657
658 #if INCLUDE_CDS
659 if (Arguments::is_dumping_archive()) {
660 if (!Arguments::has_jimage()) {
661 vm_exit_during_initialization("CDS is not supported in exploded JDK build", NULL);
662 }
663 }
664 #endif
665
666 while (cp_stream.has_next()) {
667 const char* path = cp_stream.get_next();
668
669 if (set_base_piece) {
670 // The first time through the bootstrap_search setup, it must be determined
671 // what the base or core piece of the boot loader search is. Either a java runtime
672 // image is present or this is an exploded module build situation.
673 assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
674 "Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
675 struct stat st;
676 if (os::stat(path, &st) == 0) {
677 // Directory found
678 ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
679
680 // Check for a jimage
681 if (Arguments::has_jimage()) {
682 assert(_jrt_entry == NULL, "should not setup bootstrap class search path twice");
683 _jrt_entry = new_entry;
684 assert(new_entry != NULL && new_entry->is_modules_image(), "No java runtime image present");
685 assert(_jrt_entry->jimage() != NULL, "No java runtime image");
686 }
687 } else {
688 // If path does not exist, exit
689 vm_exit_during_initialization("Unable to establish the boot loader search path", path);
690 }
691 set_base_piece = false;
692 } else {
693 // Every entry on the system boot class path after the initial base piece,
694 // which is set by os::set_boot_path(), is considered an appended entry.
695 update_class_path_entry_list(path, false, true, false);
696 }
697 }
698 }
699
700 // During an exploded modules build, each module defined to the boot loader
701 // will be added to the ClassLoader::_exploded_entries array.
702 void ClassLoader::add_to_exploded_build_list(Symbol* module_sym, TRAPS) {
703 assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
704 assert(_exploded_entries != NULL, "_exploded_entries was not initialized");
705
706 // Find the module's symbol
707 ResourceMark rm(THREAD);
708 const char *module_name = module_sym->as_C_string();
709 const char *home = Arguments::get_java_home();
710 const char file_sep = os::file_separator()[0];
711 // 10 represents the length of "modules" + 2 file separators + \0
712 size_t len = strlen(home) + strlen(module_name) + 10;
713 char *path = NEW_RESOURCE_ARRAY(char, len);
714 jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
715
716 struct stat st;
717 if (os::stat(path, &st) == 0) {
718 // Directory found
719 ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
720
721 // If the path specification is valid, enter it into this module's list.
722 // There is no need to check for duplicate modules in the exploded entry list,
723 // since no two modules with the same name can be defined to the boot loader.
724 // This is checked at module definition time in Modules::define_module.
725 if (new_entry != NULL) {
726 ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
727 module_cpl->add_to_list(new_entry);
728 {
729 MutexLocker ml(THREAD, Module_lock);
730 _exploded_entries->push(module_cpl);
731 }
732 log_info(class, load)("path: %s", path);
733 }
734 }
735 }
736
737 ClassPathEntry* ClassLoader::create_class_path_entry(const char *path, const struct stat* st,
738 bool throw_exception,
739 bool is_boot_append,
740 bool from_class_path_attr,
741 TRAPS) {
742 JavaThread* thread = JavaThread::current();
743 ClassPathEntry* new_entry = NULL;
744 if ((st->st_mode & S_IFMT) == S_IFREG) {
745 ResourceMark rm(thread);
746 // Regular file, should be a zip or jimage file
747 // Canonicalized filename
748 char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
749 if (!get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
750 // This matches the classic VM
751 if (throw_exception) {
752 THROW_MSG_(vmSymbols::java_io_IOException(), "Bad pathname", NULL);
753 } else {
754 return NULL;
755 }
756 }
757 jint error;
758 JImageFile* jimage =(*JImageOpen)(canonical_path, &error);
759 if (jimage != NULL) {
760 new_entry = new ClassPathImageEntry(jimage, canonical_path);
761 } else {
762 char* error_msg = NULL;
763 jzfile* zip;
764 {
765 // enable call to C land
766 ThreadToNativeFromVM ttn(thread);
767 HandleMark hm(thread);
768 zip = (*ZipOpen)(canonical_path, &error_msg);
769 }
770 if (zip != NULL && error_msg == NULL) {
771 new_entry = new ClassPathZipEntry(zip, path, is_boot_append, from_class_path_attr);
772 } else {
773 char *msg;
774 if (error_msg == NULL) {
775 msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(path) + 128); ;
776 jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
777 } else {
778 int len = (int)(strlen(path) + strlen(error_msg) + 128);
779 msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, len); ;
780 jio_snprintf(msg, len - 1, "error in opening JAR file <%s> %s", error_msg, path);
781 }
782 // Don't complain about bad jar files added via -Xbootclasspath/a:.
783 if (throw_exception && is_init_completed()) {
784 THROW_MSG_(vmSymbols::java_lang_ClassNotFoundException(), msg, NULL);
785 } else {
786 return NULL;
787 }
788 }
789 }
790 log_info(class, path)("opened: %s", path);
791 log_info(class, load)("opened: %s", path);
792 } else {
793 // Directory
794 new_entry = new ClassPathDirEntry(path);
795 log_info(class, load)("path: %s", path);
796 }
797 return new_entry;
798 }
799
800
801 // Create a class path zip entry for a given path (return NULL if not found
802 // or zip/JAR file cannot be opened)
803 ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
804 // check for a regular file
805 struct stat st;
806 if (os::stat(path, &st) == 0) {
807 if ((st.st_mode & S_IFMT) == S_IFREG) {
808 char canonical_path[JVM_MAXPATHLEN];
809 if (get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
810 char* error_msg = NULL;
811 jzfile* zip;
812 {
813 // enable call to C land
814 JavaThread* thread = JavaThread::current();
815 ThreadToNativeFromVM ttn(thread);
816 HandleMark hm(thread);
817 zip = (*ZipOpen)(canonical_path, &error_msg);
818 }
819 if (zip != NULL && error_msg == NULL) {
820 // create using canonical path
821 return new ClassPathZipEntry(zip, canonical_path, is_boot_append, false);
822 }
823 }
824 }
825 }
826 return NULL;
827 }
828
829 // returns true if entry already on class path
830 bool ClassLoader::contains_append_entry(const char* name) {
831 ClassPathEntry* e = _first_append_entry;
832 while (e != NULL) {
833 // assume zip entries have been canonicalized
834 if (strcmp(name, e->name()) == 0) {
835 return true;
836 }
837 e = e->next();
838 }
839 return false;
840 }
841
842 void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
843 if (new_entry != NULL) {
844 if (_last_append_entry == NULL) {
845 assert(_first_append_entry == NULL, "boot loader's append class path entry list not empty");
846 _first_append_entry = _last_append_entry = new_entry;
847 } else {
848 _last_append_entry->set_next(new_entry);
849 _last_append_entry = new_entry;
850 }
851 }
852 }
853
854 // Record the path entries specified in -cp during dump time. The recorded
855 // information will be used at runtime for loading the archived app classes.
856 //
857 // Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
858 // loading app classes. Instead, the app class are loaded by the
859 // jdk/internal/loader/ClassLoaders$AppClassLoader instance.
860 void ClassLoader::add_to_app_classpath_entries(const char* path,
861 ClassPathEntry* entry,
862 bool check_for_duplicates) {
863 #if INCLUDE_CDS
864 assert(entry != NULL, "ClassPathEntry should not be NULL");
865 ClassPathEntry* e = _app_classpath_entries;
866 if (check_for_duplicates) {
867 while (e != NULL) {
868 if (strcmp(e->name(), entry->name()) == 0) {
869 // entry already exists
870 return;
871 }
872 e = e->next();
873 }
874 }
875
876 // The entry does not exist, add to the list
877 if (_app_classpath_entries == NULL) {
878 assert(_last_app_classpath_entry == NULL, "Sanity");
879 _app_classpath_entries = _last_app_classpath_entry = entry;
880 } else {
881 _last_app_classpath_entry->set_next(entry);
882 _last_app_classpath_entry = entry;
883 }
884
885 if (entry->is_jar_file()) {
886 ClassLoaderExt::process_jar_manifest(entry, check_for_duplicates);
887 }
888 #endif
889 }
890
891 // Returns true IFF the file/dir exists and the entry was successfully created.
892 bool ClassLoader::update_class_path_entry_list(const char *path,
893 bool check_for_duplicates,
894 bool is_boot_append,
895 bool from_class_path_attr,
896 bool throw_exception) {
897 struct stat st;
898 if (os::stat(path, &st) == 0) {
899 // File or directory found
900 ClassPathEntry* new_entry = NULL;
901 Thread* THREAD = Thread::current();
902 new_entry = create_class_path_entry(path, &st, throw_exception, is_boot_append, from_class_path_attr, CHECK_(false));
903 if (new_entry == NULL) {
904 return false;
905 }
906
907 // Do not reorder the bootclasspath which would break get_system_package().
908 // Add new entry to linked list
909 if (is_boot_append) {
910 add_to_boot_append_entries(new_entry);
911 } else {
912 add_to_app_classpath_entries(path, new_entry, check_for_duplicates);
913 }
914 return true;
915 } else {
916 return false;
917 }
918 }
919
920 static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
921 ResourceMark rm;
922 int num_of_entries = module_list->length();
923 for (int i = 0; i < num_of_entries; i++) {
924 ClassPathEntry* e;
925 ModuleClassPathList* mpl = module_list->at(i);
926 tty->print("%s=", mpl->module_name()->as_C_string());
927 e = mpl->module_first_entry();
928 while (e != NULL) {
929 tty->print("%s", e->name());
930 e = e->next();
931 if (e != NULL) {
932 tty->print("%s", os::path_separator());
933 }
934 }
935 tty->print(" ;");
936 }
937 }
938
939 void ClassLoader::print_bootclasspath() {
940 ClassPathEntry* e;
941 tty->print("[bootclasspath= ");
942
943 // Print --patch-module module/path specifications first
944 if (_patch_mod_entries != NULL) {
945 print_module_entry_table(_patch_mod_entries);
946 }
947
948 // [jimage | exploded modules build]
949 if (has_jrt_entry()) {
950 // Print the location of the java runtime image
951 tty->print("%s ;", _jrt_entry->name());
952 } else {
953 // Print exploded module build path specifications
954 if (_exploded_entries != NULL) {
955 print_module_entry_table(_exploded_entries);
956 }
957 }
958
959 // appended entries
960 e = _first_append_entry;
961 while (e != NULL) {
962 tty->print("%s ;", e->name());
963 e = e->next();
964 }
965 tty->print_cr("]");
966 }
967
968 void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
969 void* func = os::dll_lookup(lib, name);
970 if (func == NULL) {
971 char msg[256] = "";
972 jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
973 vm_exit_during_initialization(msg, path);
974 }
975 return func;
976 }
977
978 void ClassLoader::load_java_library() {
979 assert(CanonicalizeEntry == NULL, "should not load java library twice");
980 void *javalib_handle = os::native_java_library();
981 if (javalib_handle == NULL) {
982 vm_exit_during_initialization("Unable to load java library", NULL);
983 }
984
985 CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", NULL));
986 }
987
988 void ClassLoader::load_zip_library() {
989 assert(ZipOpen == NULL, "should not load zip library twice");
990 char path[JVM_MAXPATHLEN];
991 char ebuf[1024];
992 void* handle = NULL;
993 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "zip")) {
994 handle = os::dll_load(path, ebuf, sizeof ebuf);
995 }
996 if (handle == NULL) {
997 vm_exit_during_initialization("Unable to load zip library", path);
998 }
999
1000 ZipOpen = CAST_TO_FN_PTR(ZipOpen_t, dll_lookup(handle, "ZIP_Open", path));
1001 ZipClose = CAST_TO_FN_PTR(ZipClose_t, dll_lookup(handle, "ZIP_Close", path));
1002 FindEntry = CAST_TO_FN_PTR(FindEntry_t, dll_lookup(handle, "ZIP_FindEntry", path));
1003 ReadEntry = CAST_TO_FN_PTR(ReadEntry_t, dll_lookup(handle, "ZIP_ReadEntry", path));
1004 GetNextEntry = CAST_TO_FN_PTR(GetNextEntry_t, dll_lookup(handle, "ZIP_GetNextEntry", path));
1005 Crc32 = CAST_TO_FN_PTR(Crc32_t, dll_lookup(handle, "ZIP_CRC32", path));
1006 }
1007
1008 void ClassLoader::load_jimage_library() {
1009 assert(JImageOpen == NULL, "should not load jimage library twice");
1010 char path[JVM_MAXPATHLEN];
1011 char ebuf[1024];
1012 void* handle = NULL;
1013 if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
1014 handle = os::dll_load(path, ebuf, sizeof ebuf);
1015 }
1016 if (handle == NULL) {
1017 vm_exit_during_initialization("Unable to load jimage library", path);
1018 }
1019
1020 JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
1021 JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
1022 JImagePackageToModule = CAST_TO_FN_PTR(JImagePackageToModule_t, dll_lookup(handle, "JIMAGE_PackageToModule", path));
1023 JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
1024 JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
1025 JImageResourceIterator = CAST_TO_FN_PTR(JImageResourceIterator_t, dll_lookup(handle, "JIMAGE_ResourceIterator", path));
1026 }
1027
1028 int ClassLoader::crc32(int crc, const char* buf, int len) {
1029 return (*Crc32)(crc, (const jbyte*)buf, len);
1030 }
1031
1032 // Function add_package extracts the package from the fully qualified class name
1033 // and checks if the package is in the boot loader's package entry table. If so,
1034 // then it sets the classpath_index in the package entry record.
1035 //
1036 // The classpath_index field is used to find the entry on the boot loader class
1037 // path for packages with classes loaded by the boot loader from -Xbootclasspath/a
1038 // in an unnamed module. It is also used to indicate (for all packages whose
1039 // classes are loaded by the boot loader) that at least one of the package's
1040 // classes has been loaded.
1041 bool ClassLoader::add_package(const char *fullq_class_name, s2 classpath_index, TRAPS) {
1042 assert(fullq_class_name != NULL, "just checking");
1043
1044 // Get package name from fully qualified class name.
1045 ResourceMark rm(THREAD);
1046 const char *cp = package_from_name(fullq_class_name);
1047 if (cp != NULL) {
1048 PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();
1049 TempNewSymbol pkg_symbol = SymbolTable::new_symbol(cp);
1050 PackageEntry* pkg_entry = pkg_entry_tbl->lookup_only(pkg_symbol);
1051 if (pkg_entry != NULL) {
1052 assert(classpath_index != -1, "Unexpected classpath_index");
1053 pkg_entry->set_classpath_index(classpath_index);
1054 } else {
1055 return false;
1056 }
1057 }
1058 return true;
1059 }
1060
1061 oop ClassLoader::get_system_package(const char* name, TRAPS) {
1062 // Look up the name in the boot loader's package entry table.
1063 if (name != NULL) {
1064 TempNewSymbol package_sym = SymbolTable::new_symbol(name);
1065 // Look for the package entry in the boot loader's package entry table.
1066 PackageEntry* package =
1067 ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
1068
1069 // Return NULL if package does not exist or if no classes in that package
1070 // have been loaded.
1071 if (package != NULL && package->has_loaded_class()) {
1072 ModuleEntry* module = package->module();
1073 if (module->location() != NULL) {
1074 ResourceMark rm(THREAD);
1075 Handle ml = java_lang_String::create_from_str(
1076 module->location()->as_C_string(), THREAD);
1077 return ml();
1078 }
1079 // Return entry on boot loader class path.
1080 Handle cph = java_lang_String::create_from_str(
1081 ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
1082 return cph();
1083 }
1084 }
1085 return NULL;
1086 }
1087
1088 objArrayOop ClassLoader::get_system_packages(TRAPS) {
1089 ResourceMark rm(THREAD);
1090 // List of pointers to PackageEntrys that have loaded classes.
1091 GrowableArray<PackageEntry*>* loaded_class_pkgs = new GrowableArray<PackageEntry*>(50);
1092 {
1093 MutexLocker ml(THREAD, Module_lock);
1094
1095 PackageEntryTable* pe_table =
1096 ClassLoaderData::the_null_class_loader_data()->packages();
1097
1098 // Collect the packages that have at least one loaded class.
1099 for (int x = 0; x < pe_table->table_size(); x++) {
1100 for (PackageEntry* package_entry = pe_table->bucket(x);
1101 package_entry != NULL;
1102 package_entry = package_entry->next()) {
1103 if (package_entry->has_loaded_class()) {
1104 loaded_class_pkgs->append(package_entry);
1105 }
1106 }
1107 }
1108 }
1109
1110
1111 // Allocate objArray and fill with java.lang.String
1112 objArrayOop r = oopFactory::new_objArray(SystemDictionary::String_klass(),
1113 loaded_class_pkgs->length(), CHECK_NULL);
1114 objArrayHandle result(THREAD, r);
1115 for (int x = 0; x < loaded_class_pkgs->length(); x++) {
1116 PackageEntry* package_entry = loaded_class_pkgs->at(x);
1117 Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
1118 result->obj_at_put(x, str());
1119 }
1120 return result();
1121 }
1122
1123 // caller needs ResourceMark
1124 const char* ClassLoader::file_name_for_class_name(const char* class_name,
1125 int class_name_len) {
1126 assert(class_name != NULL, "invariant");
1127 assert((int)strlen(class_name) == class_name_len, "invariant");
1128
1129 static const char class_suffix[] = ".class";
1130 size_t class_suffix_len = sizeof(class_suffix);
1131
1132 char* const file_name = NEW_RESOURCE_ARRAY(char,
1133 class_name_len +
1134 class_suffix_len); // includes term NULL
1135
1136 strncpy(file_name, class_name, class_name_len);
1137 strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
1138
1139 return file_name;
1140 }
1141
1142 ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
1143 const GrowableArray<ModuleClassPathList*>* const module_list) {
1144 int num_of_entries = module_list->length();
1145 const Symbol* class_module_name = mod_entry->name();
1146
1147 // Loop through all the modules in either the patch-module or exploded entries looking for module
1148 for (int i = 0; i < num_of_entries; i++) {
1149 ModuleClassPathList* module_cpl = module_list->at(i);
1150 Symbol* module_cpl_name = module_cpl->module_name();
1151
1152 if (module_cpl_name->fast_compare(class_module_name) == 0) {
1153 // Class' module has been located.
1154 return module_cpl->module_first_entry();
1155 }
1156 }
1157 return NULL;
1158 }
1159
1160
1161 // Search either the patch-module or exploded build entries for class.
1162 ClassFileStream* ClassLoader::search_module_entries(const GrowableArray<ModuleClassPathList*>* const module_list,
1163 const char* const class_name,
1164 const char* const file_name,
1165 TRAPS) {
1166 ClassFileStream* stream = NULL;
1167
1168 // Find the class' defining module in the boot loader's module entry table
1169 PackageEntry* pkg_entry = get_package_entry(class_name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
1170 ModuleEntry* mod_entry = (pkg_entry != NULL) ? pkg_entry->module() : NULL;
1171
1172 // If the module system has not defined java.base yet, then
1173 // classes loaded are assumed to be defined to java.base.
1174 // When java.base is eventually defined by the module system,
1175 // all packages of classes that have been previously loaded
1176 // are verified in ModuleEntryTable::verify_javabase_packages().
1177 if (!Universe::is_module_initialized() &&
1178 !ModuleEntryTable::javabase_defined() &&
1179 mod_entry == NULL) {
1180 mod_entry = ModuleEntryTable::javabase_moduleEntry();
1181 }
1182
1183 // The module must be a named module
1184 ClassPathEntry* e = NULL;
1185 if (mod_entry != NULL && mod_entry->is_named()) {
1186 if (module_list == _exploded_entries) {
1187 // The exploded build entries can be added to at any time so a lock is
1188 // needed when searching them.
1189 assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
1190 MutexLocker ml(THREAD, Module_lock);
1191 e = find_first_module_cpe(mod_entry, module_list);
1192 } else {
1193 e = find_first_module_cpe(mod_entry, module_list);
1194 }
1195 }
1196
1197 // Try to load the class from the module's ClassPathEntry list.
1198 while (e != NULL) {
1199 stream = e->open_stream(file_name, CHECK_NULL);
1200 // No context.check is required since CDS is not supported
1201 // for an exploded modules build or if --patch-module is specified.
1202 if (NULL != stream) {
1203 return stream;
1204 }
1205 e = e->next();
1206 }
1207 // If the module was located, break out even if the class was not
1208 // located successfully from that module's ClassPathEntry list.
1209 // There will not be another valid entry for that module.
1210 return NULL;
1211 }
1212
1213 // Called by the boot classloader to load classes
1214 InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
1215 assert(name != NULL, "invariant");
1216 assert(THREAD->is_Java_thread(), "must be a JavaThread");
1217
1218 ResourceMark rm(THREAD);
1219 HandleMark hm(THREAD);
1220
1221 const char* const class_name = name->as_C_string();
1222
1223 EventMark m("loading class %s", class_name);
1224
1225 const char* const file_name = file_name_for_class_name(class_name,
1226 name->utf8_length());
1227 assert(file_name != NULL, "invariant");
1228
1229 // Lookup stream for parsing .class file
1230 ClassFileStream* stream = NULL;
1231 s2 classpath_index = 0;
1232 ClassPathEntry* e = NULL;
1233
1234 // If search_append_only is true, boot loader visibility boundaries are
1235 // set to be _first_append_entry to the end. This includes:
1236 // [-Xbootclasspath/a]; [jvmti appended entries]
1237 //
1238 // If search_append_only is false, boot loader visibility boundaries are
1239 // set to be the --patch-module entries plus the base piece. This includes:
1240 // [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
1241 //
1242
1243 // Load Attempt #1: --patch-module
1244 // Determine the class' defining module. If it appears in the _patch_mod_entries,
1245 // attempt to load the class from those locations specific to the module.
1246 // Specifications to --patch-module can contain a partial number of classes
1247 // that are part of the overall module definition. So if a particular class is not
1248 // found within its module specification, the search should continue to Load Attempt #2.
1249 // Note: The --patch-module entries are never searched if the boot loader's
1250 // visibility boundary is limited to only searching the append entries.
1251 if (_patch_mod_entries != NULL && !search_append_only) {
1252 // At CDS dump time, the --patch-module entries are ignored. That means a
1253 // class is still loaded from the runtime image even if it might
1254 // appear in the _patch_mod_entries. The runtime shared class visibility
1255 // check will determine if a shared class is visible based on the runtime
1256 // environemnt, including the runtime --patch-module setting.
1257 //
1258 // DynamicDumpSharedSpaces requires UseSharedSpaces to be enabled. Since --patch-module
1259 // is not supported with UseSharedSpaces, it is not supported with DynamicDumpSharedSpaces.
1260 assert(!DynamicDumpSharedSpaces, "sanity");
1261 if (!DumpSharedSpaces) {
1262 stream = search_module_entries(_patch_mod_entries, class_name, file_name, CHECK_NULL);
1263 }
1264 }
1265
1266 // Load Attempt #2: [jimage | exploded build]
1267 if (!search_append_only && (NULL == stream)) {
1268 if (has_jrt_entry()) {
1269 e = _jrt_entry;
1270 stream = _jrt_entry->open_stream(file_name, CHECK_NULL);
1271 } else {
1272 // Exploded build - attempt to locate class in its defining module's location.
1273 assert(_exploded_entries != NULL, "No exploded build entries present");
1274 stream = search_module_entries(_exploded_entries, class_name, file_name, CHECK_NULL);
1275 }
1276 }
1277
1278 // Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
1279 if (search_append_only && (NULL == stream)) {
1280 // For the boot loader append path search, the starting classpath_index
1281 // for the appended piece is always 1 to account for either the
1282 // _jrt_entry or the _exploded_entries.
1283 assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
1284 classpath_index = 1;
1285
1286 e = _first_append_entry;
1287 while (e != NULL) {
1288 stream = e->open_stream(file_name, CHECK_NULL);
1289 if (NULL != stream) {
1290 break;
1291 }
1292 e = e->next();
1293 ++classpath_index;
1294 }
1295 }
1296
1297 if (NULL == stream) {
1298 return NULL;
1299 }
1300
1301 stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
1302
1303 ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
1304 Handle protection_domain;
1305
1306 InstanceKlass* result = KlassFactory::create_from_stream(stream,
1307 name,
1308 loader_data,
1309 protection_domain,
1310 NULL, // unsafe_anonymous_host
1311 NULL, // cp_patches
1312 THREAD);
1313 if (HAS_PENDING_EXCEPTION) {
1314 if (DumpSharedSpaces) {
1315 log_error(cds)("Preload Error: Failed to load %s", class_name);
1316 }
1317 return NULL;
1318 }
1319
1320 if (!add_package(file_name, classpath_index, THREAD)) {
1321 return NULL;
1322 }
1323
1324 return result;
1325 }
1326
1327 #if INCLUDE_CDS
1328 char* ClassLoader::skip_uri_protocol(char* source) {
1329 if (strncmp(source, "file:", 5) == 0) {
1330 // file: protocol path could start with file:/ or file:///
1331 // locate the char after all the forward slashes
1332 int offset = 5;
1333 while (*(source + offset) == '/') {
1334 offset++;
1335 }
1336 source += offset;
1337 // for non-windows platforms, move back one char as the path begins with a '/'
1338 #ifndef _WINDOWS
1339 source -= 1;
1340 #endif
1341 } else if (strncmp(source, "jrt:/", 5) == 0) {
1342 source += 5;
1343 }
1344 return source;
1345 }
1346
1347 // Record the shared classpath index and loader type for classes loaded
1348 // by the builtin loaders at dump time.
1349 void ClassLoader::record_result(InstanceKlass* ik, const ClassFileStream* stream, TRAPS) {
1350 Arguments::assert_is_dumping_archive();
1351 assert(stream != NULL, "sanity");
1352
1353 if (ik->is_unsafe_anonymous()) {
1354 // We do not archive unsafe anonymous classes.
1355 return;
1356 }
1357
1358 oop loader = ik->class_loader();
1359 char* src = (char*)stream->source();
1360 if (src == NULL) {
1361 if (loader == NULL) {
1362 // JFR classes
1363 ik->set_shared_classpath_index(0);
1364 ik->set_shared_class_loader_type(ClassLoader::BOOT_LOADER);
1365 }
1366 return;
1367 }
1368
1369 assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
1370
1371 ResourceMark rm(THREAD);
1372 int classpath_index = -1;
1373 PackageEntry* pkg_entry = ik->package();
1374
1375 if (FileMapInfo::get_number_of_shared_paths() > 0) {
1376 char* canonical_path_table_entry = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
1377
1378 // save the path from the file: protocol or the module name from the jrt: protocol
1379 // if no protocol prefix is found, path is the same as stream->source()
1380 char* path = skip_uri_protocol(src);
1381 char* canonical_class_src_path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
1382 bool success = get_canonical_path(path, canonical_class_src_path, JVM_MAXPATHLEN);
1383 // The path is from the ClassFileStream. Since a ClassFileStream has been created successfully in functions
1384 // such as ClassLoader::load_class(), its source path must be valid.
1385 assert(success, "must be valid path");
1386 for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
1387 SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
1388 success = get_canonical_path(ent->name(), canonical_path_table_entry, JVM_MAXPATHLEN);
1389 // A shared path has been validated during its creation in ClassLoader::create_class_path_entry(),
1390 // it must be valid here.
1391 assert(success, "must be valid path");
1392 // If the path (from the class stream source) is the same as the shared
1393 // class or module path, then we have a match.
1394 if (strcmp(canonical_path_table_entry, canonical_class_src_path) == 0) {
1395 // NULL pkg_entry and pkg_entry in an unnamed module implies the class
1396 // is from the -cp or boot loader append path which consists of -Xbootclasspath/a
1397 // and jvmti appended entries.
1398 if ((pkg_entry == NULL) || (pkg_entry->in_unnamed_module())) {
1399 // Ensure the index is within the -cp range before assigning
1400 // to the classpath_index.
1401 if (SystemDictionary::is_system_class_loader(loader) &&
1402 (i >= ClassLoaderExt::app_class_paths_start_index()) &&
1403 (i < ClassLoaderExt::app_module_paths_start_index())) {
1404 classpath_index = i;
1405 break;
1406 } else {
1407 if ((i >= 1) &&
1408 (i < ClassLoaderExt::app_class_paths_start_index())) {
1409 // The class must be from boot loader append path which consists of
1410 // -Xbootclasspath/a and jvmti appended entries.
1411 assert(loader == NULL, "sanity");
1412 classpath_index = i;
1413 break;
1414 }
1415 }
1416 } else {
1417 // A class from a named module from the --module-path. Ensure the index is
1418 // within the --module-path range before assigning to the classpath_index.
1419 if ((pkg_entry != NULL) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
1420 if (i >= ClassLoaderExt::app_module_paths_start_index() &&
1421 i < FileMapInfo::get_number_of_shared_paths()) {
1422 classpath_index = i;
1423 break;
1424 }
1425 }
1426 }
1427 }
1428 // for index 0 and the stream->source() is the modules image or has the jrt: protocol.
1429 // The class must be from the runtime modules image.
1430 if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
1431 classpath_index = i;
1432 break;
1433 }
1434 }
1435
1436 // No path entry found for this class. Must be a shared class loaded by the
1437 // user defined classloader.
1438 if (classpath_index < 0) {
1439 assert(ik->shared_classpath_index() < 0, "Sanity");
1440 ik->set_shared_classpath_index(UNREGISTERED_INDEX);
1441 SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
1442 return;
1443 }
1444 } else {
1445 // The shared path table is set up after module system initialization.
1446 // The path table contains no entry before that. Any classes loaded prior
1447 // to the setup of the shared path table must be from the modules image.
1448 assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
1449 assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
1450 classpath_index = 0;
1451 }
1452
1453 const char* const class_name = ik->name()->as_C_string();
1454 const char* const file_name = file_name_for_class_name(class_name,
1455 ik->name()->utf8_length());
1456 assert(file_name != NULL, "invariant");
1457
1458 ClassLoaderExt::record_result(classpath_index, ik, THREAD);
1459 }
1460 #endif // INCLUDE_CDS
1461
1462 // Initialize the class loader's access to methods in libzip. Parse and
1463 // process the boot classpath into a list ClassPathEntry objects. Once
1464 // this list has been created, it must not change order (see class PackageInfo)
1465 // it can be appended to and is by jvmti and the kernel vm.
1466
1467 void ClassLoader::initialize() {
1468 EXCEPTION_MARK;
1469
1470 if (UsePerfData) {
1471 // jvmstat performance counters
1472 NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
1473 NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
1474 NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
1475 NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
1476 NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
1477 NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
1478 NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
1479 NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
1480 NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
1481 NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
1482
1483 NEWPERFTICKCOUNTER(_perf_class_parse_time, SUN_CLS, "parseClassTime");
1484 NEWPERFTICKCOUNTER(_perf_class_parse_selftime, SUN_CLS, "parseClassTime.self");
1485 NEWPERFTICKCOUNTER(_perf_sys_class_lookup_time, SUN_CLS, "lookupSysClassTime");
1486 NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
1487 NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
1488 NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
1489 NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
1490 NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
1491 NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
1492 NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
1493 NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
1494 NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
1495 NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
1496
1497
1498 // The following performance counters are added for measuring the impact
1499 // of the bug fix of 6365597. They are mainly focused on finding out
1500 // the behavior of system & user-defined classloader lock, whether
1501 // ClassLoader.loadClass/findClass is being called synchronized or not.
1502 NEWPERFEVENTCOUNTER(_sync_systemLoaderLockContentionRate, SUN_CLS,
1503 "systemLoaderLockContentionRate");
1504 NEWPERFEVENTCOUNTER(_sync_nonSystemLoaderLockContentionRate, SUN_CLS,
1505 "nonSystemLoaderLockContentionRate");
1506 NEWPERFEVENTCOUNTER(_sync_JVMFindLoadedClassLockFreeCounter, SUN_CLS,
1507 "jvmFindLoadedClassNoLockCalls");
1508 NEWPERFEVENTCOUNTER(_sync_JVMDefineClassLockFreeCounter, SUN_CLS,
1509 "jvmDefineClassNoLockCalls");
1510
1511 NEWPERFEVENTCOUNTER(_sync_JNIDefineClassLockFreeCounter, SUN_CLS,
1512 "jniDefineClassNoLockCalls");
1513
1514 NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS,
1515 "unsafeDefineClassCalls");
1516 }
1517
1518 // lookup java library entry points
1519 load_java_library();
1520 // lookup zip library entry points
1521 load_zip_library();
1522 // jimage library entry points are loaded below, in lookup_vm_options
1523 setup_bootstrap_search_path();
1524 }
1525
1526 char* lookup_vm_resource(JImageFile *jimage, const char *jimage_version, const char *path) {
1527 jlong size;
1528 JImageLocationRef location = (*JImageFindResource)(jimage, "java.base", jimage_version, path, &size);
1529 if (location == 0)
1530 return NULL;
1531 char *val = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
1532 (*JImageGetResource)(jimage, location, val, size);
1533 val[size] = '\0';
1534 return val;
1535 }
1536
1537 // Lookup VM options embedded in the modules jimage file
1538 char* ClassLoader::lookup_vm_options() {
1539 jint error;
1540 char modules_path[JVM_MAXPATHLEN];
1541 const char* fileSep = os::file_separator();
1542
1543 // Initialize jimage library entry points
1544 load_jimage_library();
1545
1546 jio_snprintf(modules_path, JVM_MAXPATHLEN, "%s%slib%smodules", Arguments::get_java_home(), fileSep, fileSep);
1547 JImageFile* jimage =(*JImageOpen)(modules_path, &error);
1548 if (jimage == NULL) {
1549 return NULL;
1550 }
1551
1552 const char *jimage_version = get_jimage_version_string();
1553 char *options = lookup_vm_resource(jimage, jimage_version, "jdk/internal/vm/options");
1554
1555 (*JImageClose)(jimage);
1556 return options;
1557 }
1558
1559 #if INCLUDE_CDS
1560 void ClassLoader::initialize_shared_path() {
1561 if (Arguments::is_dumping_archive()) {
1562 ClassLoaderExt::setup_search_paths();
1563 }
1564 }
1565
1566 void ClassLoader::initialize_module_path(TRAPS) {
1567 if (Arguments::is_dumping_archive()) {
1568 ClassLoaderExt::setup_module_paths(THREAD);
1569 FileMapInfo::allocate_shared_path_table();
1570 }
1571 }
1572 #endif
1573
1574 jlong ClassLoader::classloader_time_ms() {
1575 return UsePerfData ?
1576 Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
1577 }
1578
1579 jlong ClassLoader::class_init_count() {
1580 return UsePerfData ? _perf_classes_inited->get_value() : -1;
1581 }
1582
1583 jlong ClassLoader::class_init_time_ms() {
1584 return UsePerfData ?
1585 Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
1586 }
1587
1588 jlong ClassLoader::class_verify_time_ms() {
1589 return UsePerfData ?
1590 Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
1591 }
1592
1593 jlong ClassLoader::class_link_count() {
1594 return UsePerfData ? _perf_classes_linked->get_value() : -1;
1595 }
1596
1597 jlong ClassLoader::class_link_time_ms() {
1598 return UsePerfData ?
1599 Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
1600 }
1601
1602 int ClassLoader::compute_Object_vtable() {
1603 // hardwired for JDK1.2 -- would need to duplicate class file parsing
1604 // code to determine actual value from file
1605 // Would be value '11' if finals were in vtable
1606 int JDK_1_2_Object_vtable_size = 5;
1607 return JDK_1_2_Object_vtable_size * vtableEntry::size();
1608 }
1609
1610
1611 void classLoader_init1() {
1612 ClassLoader::initialize();
1613 }
1614
1615 // Complete the ClassPathEntry setup for the boot loader
1616 void ClassLoader::classLoader_init2(TRAPS) {
1617 // Setup the list of module/path pairs for --patch-module processing
1618 // This must be done after the SymbolTable is created in order
1619 // to use fast_compare on module names instead of a string compare.
1620 if (Arguments::get_patch_mod_prefix() != NULL) {
1621 setup_patch_mod_entries();
1622 }
1623
1624 // Create the ModuleEntry for java.base (must occur after setup_patch_mod_entries
1625 // to successfully determine if java.base has been patched)
1626 create_javabase();
1627
1628 // Setup the initial java.base/path pair for the exploded build entries.
1629 // As more modules are defined during module system initialization, more
1630 // entries will be added to the exploded build array.
1631 if (!has_jrt_entry()) {
1632 assert(!DumpSharedSpaces, "DumpSharedSpaces not supported with exploded module builds");
1633 assert(!DynamicDumpSharedSpaces, "DynamicDumpSharedSpaces not supported with exploded module builds");
1634 assert(!UseSharedSpaces, "UsedSharedSpaces not supported with exploded module builds");
1635 // Set up the boot loader's _exploded_entries list. Note that this gets
1636 // done before loading any classes, by the same thread that will
1637 // subsequently do the first class load. So, no lock is needed for this.
1638 assert(_exploded_entries == NULL, "Should only get initialized once");
1639 _exploded_entries = new (ResourceObj::C_HEAP, mtModule)
1640 GrowableArray<ModuleClassPathList*>(EXPLODED_ENTRY_SIZE, true);
1641 add_to_exploded_build_list(vmSymbols::java_base(), CHECK);
1642 }
1643 }
1644
1645 bool ClassLoader::get_canonical_path(const char* orig, char* out, int len) {
1646 assert(orig != NULL && out != NULL && len > 0, "bad arguments");
1647 JavaThread* THREAD = JavaThread::current();
1648 ResourceMark rm(THREAD);
1649
1650 // os::native_path writes into orig_copy
1651 char* orig_copy = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, strlen(orig)+1);
1652 strcpy(orig_copy, orig);
1653 if ((CanonicalizeEntry)(os::native_path(orig_copy), out, len) < 0) {
1654 return false;
1655 }
1656 return true;
1657 }
1658
1659 void ClassLoader::create_javabase() {
1660 Thread* THREAD = Thread::current();
1661
1662 // Create java.base's module entry for the boot
1663 // class loader prior to loading j.l.Ojbect.
1664 ClassLoaderData* null_cld = ClassLoaderData::the_null_class_loader_data();
1665
1666 // Get module entry table
1667 ModuleEntryTable* null_cld_modules = null_cld->modules();
1668 if (null_cld_modules == NULL) {
1669 vm_exit_during_initialization("No ModuleEntryTable for the boot class loader");
1670 }
1671
1672 {
1673 MutexLocker ml(THREAD, Module_lock);
1674 ModuleEntry* jb_module = null_cld_modules->locked_create_entry(Handle(),
1675 false, vmSymbols::java_base(), NULL, NULL, null_cld);
1676 if (jb_module == NULL) {
1677 vm_exit_during_initialization("Unable to create ModuleEntry for " JAVA_BASE_NAME);
1678 }
1679 ModuleEntryTable::set_javabase_moduleEntry(jb_module);
1680 }
1681 }
1682
1683 // Please keep following two functions at end of this file. With them placed at top or in middle of the file,
1684 // they could get inlined by agressive compiler, an unknown trick, see bug 6966589.
1685 void PerfClassTraceTime::initialize() {
1686 if (!UsePerfData) return;
1687
1688 if (_eventp != NULL) {
1689 // increment the event counter
1690 _eventp->inc();
1691 }
1692
1693 // stop the current active thread-local timer to measure inclusive time
1694 _prev_active_event = -1;
1695 for (int i=0; i < EVENT_TYPE_COUNT; i++) {
1696 if (_timers[i].is_active()) {
1697 assert(_prev_active_event == -1, "should have only one active timer");
1698 _prev_active_event = i;
1699 _timers[i].stop();
1700 }
1701 }
1702
1703 if (_recursion_counters == NULL || (_recursion_counters[_event_type])++ == 0) {
1704 // start the inclusive timer if not recursively called
1705 _t.start();
1706 }
1707
1708 // start thread-local timer of the given event type
1709 if (!_timers[_event_type].is_active()) {
1710 _timers[_event_type].start();
1711 }
1712 }
1713
1714 PerfClassTraceTime::~PerfClassTraceTime() {
1715 if (!UsePerfData) return;
1716
1717 // stop the thread-local timer as the event completes
1718 // and resume the thread-local timer of the event next on the stack
1719 _timers[_event_type].stop();
1720 jlong selftime = _timers[_event_type].ticks();
1721
1722 if (_prev_active_event >= 0) {
1723 _timers[_prev_active_event].start();
1724 }
1725
1726 if (_recursion_counters != NULL && --(_recursion_counters[_event_type]) > 0) return;
1727
1728 // increment the counters only on the leaf call
1729 _t.stop();
1730 _timep->inc(_t.ticks());
1731 if (_selftimep != NULL) {
1732 _selftimep->inc(selftime);
1733 }
1734 // add all class loading related event selftime to the accumulated time counter
1735 ClassLoader::perf_accumulated_time()->inc(selftime);
1736
1737 // reset the timer
1738 _timers[_event_type].reset();
1739 }