JDK14/Java14源码在线阅读
/*
* Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*
*/
#include "precompiled.hpp"
#include "jvm.h"
#include "jimage.hpp"
#include "classfile/classFileStream.hpp"
#include "classfile/classLoader.inline.hpp"
#include "classfile/classLoaderData.inline.hpp"
#include "classfile/classLoaderExt.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/moduleEntry.hpp"
#include "classfile/modules.hpp"
#include "classfile/packageEntry.hpp"
#include "classfile/klassFactory.hpp"
#include "classfile/symbolTable.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/systemDictionaryShared.hpp"
#include "classfile/vmSymbols.hpp"
#include "compiler/compileBroker.hpp"
#include "interpreter/bytecodeStream.hpp"
#include "interpreter/oopMapCache.hpp"
#include "logging/log.hpp"
#include "logging/logStream.hpp"
#include "logging/logTag.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/filemap.hpp"
#include "memory/oopFactory.hpp"
#include "memory/resourceArea.hpp"
#include "memory/universe.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/instanceRefKlass.hpp"
#include "oops/method.inline.hpp"
#include "oops/objArrayOop.inline.hpp"
#include "oops/oop.inline.hpp"
#include "oops/symbol.hpp"
#include "prims/jvm_misc.hpp"
#include "runtime/arguments.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/init.hpp"
#include "runtime/interfaceSupport.inline.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/os.inline.hpp"
#include "runtime/threadCritical.hpp"
#include "runtime/timer.hpp"
#include "runtime/vm_version.hpp"
#include "services/management.hpp"
#include "services/threadService.hpp"
#include "utilities/classpathStream.hpp"
#include "utilities/events.hpp"
#include "utilities/hashtable.inline.hpp"
#include "utilities/macros.hpp"
// Entry point in java.dll for path canonicalization
typedef int (*canonicalize_fn_t)(const char *orig, char *out, int len);
static canonicalize_fn_t CanonicalizeEntry = NULL;
// Entry points in zip.dll for loading zip/jar file entries
typedef void * * (*ZipOpen_t)(const char *name, char **pmsg);
typedef void (*ZipClose_t)(jzfile *zip);
typedef jzentry* (*FindEntry_t)(jzfile *zip, const char *name, jint *sizeP, jint *nameLen);
typedef jboolean (*ReadEntry_t)(jzfile *zip, jzentry *entry, unsigned char *buf, char *namebuf);
typedef jzentry* (*GetNextEntry_t)(jzfile *zip, jint n);
typedef jint (*Crc32_t)(jint crc, const jbyte *buf, jint len);
static ZipOpen_t ZipOpen = NULL;
static ZipClose_t ZipClose = NULL;
static FindEntry_t FindEntry = NULL;
static ReadEntry_t ReadEntry = NULL;
static GetNextEntry_t GetNextEntry = NULL;
static Crc32_t Crc32 = NULL;
// Entry points for jimage.dll for loading jimage file entries
static JImageOpen_t JImageOpen = NULL;
static JImageClose_t JImageClose = NULL;
static JImagePackageToModule_t JImagePackageToModule = NULL;
static JImageFindResource_t JImageFindResource = NULL;
static JImageGetResource_t JImageGetResource = NULL;
static JImageResourceIterator_t JImageResourceIterator = NULL;
// Globals
PerfCounter* ClassLoader::_perf_accumulated_time = NULL;
PerfCounter* ClassLoader::_perf_classes_inited = NULL;
PerfCounter* ClassLoader::_perf_class_init_time = NULL;
PerfCounter* ClassLoader::_perf_class_init_selftime = NULL;
PerfCounter* ClassLoader::_perf_classes_verified = NULL;
PerfCounter* ClassLoader::_perf_class_verify_time = NULL;
PerfCounter* ClassLoader::_perf_class_verify_selftime = NULL;
PerfCounter* ClassLoader::_perf_classes_linked = NULL;
PerfCounter* ClassLoader::_perf_class_link_time = NULL;
PerfCounter* ClassLoader::_perf_class_link_selftime = NULL;
PerfCounter* ClassLoader::_perf_class_parse_time = NULL;
PerfCounter* ClassLoader::_perf_class_parse_selftime = NULL;
PerfCounter* ClassLoader::_perf_sys_class_lookup_time = NULL;
PerfCounter* ClassLoader::_perf_shared_classload_time = NULL;
PerfCounter* ClassLoader::_perf_sys_classload_time = NULL;
PerfCounter* ClassLoader::_perf_app_classload_time = NULL;
PerfCounter* ClassLoader::_perf_app_classload_selftime = NULL;
PerfCounter* ClassLoader::_perf_app_classload_count = NULL;
PerfCounter* ClassLoader::_perf_define_appclasses = NULL;
PerfCounter* ClassLoader::_perf_define_appclass_time = NULL;
PerfCounter* ClassLoader::_perf_define_appclass_selftime = NULL;
PerfCounter* ClassLoader::_perf_app_classfile_bytes_read = NULL;
PerfCounter* ClassLoader::_perf_sys_classfile_bytes_read = NULL;
PerfCounter* ClassLoader::_sync_systemLoaderLockContentionRate = NULL;
PerfCounter* ClassLoader::_sync_nonSystemLoaderLockContentionRate = NULL;
PerfCounter* ClassLoader::_sync_JVMFindLoadedClassLockFreeCounter = NULL;
PerfCounter* ClassLoader::_sync_JVMDefineClassLockFreeCounter = NULL;
PerfCounter* ClassLoader::_sync_JNIDefineClassLockFreeCounter = NULL;
PerfCounter* ClassLoader::_unsafe_defineClassCallCounter = NULL;
GrowableArray<ModuleClassPathList*>* ClassLoader::_patch_mod_entries = NULL;
GrowableArray<ModuleClassPathList*>* ClassLoader::_exploded_entries = NULL;
ClassPathEntry* ClassLoader::_jrt_entry = NULL;
ClassPathEntry* ClassLoader::_first_append_entry = NULL;
ClassPathEntry* ClassLoader::_last_append_entry = NULL;
#if INCLUDE_CDS
ClassPathEntry* ClassLoader::_app_classpath_entries = NULL;
ClassPathEntry* ClassLoader::_last_app_classpath_entry = NULL;
ClassPathEntry* ClassLoader::_module_path_entries = NULL;
ClassPathEntry* ClassLoader::_last_module_path_entry = NULL;
#endif
// helper routines
bool string_starts_with(const char* str, const char* str_to_find) {
size_t str_len = strlen(str);
size_t str_to_find_len = strlen(str_to_find);
if (str_to_find_len > str_len) {
return false;
}
return (strncmp(str, str_to_find, str_to_find_len) == 0);
}
static const char* get_jimage_version_string() {
static char version_string[10] = "";
if (version_string[0] == '\0') {
jio_snprintf(version_string, sizeof(version_string), "%d.%d",
VM_Version::vm_major_version(), VM_Version::vm_minor_version());
}
return (const char*)version_string;
}
bool ClassLoader::string_ends_with(const char* str, const char* str_to_find) {
size_t str_len = strlen(str);
size_t str_to_find_len = strlen(str_to_find);
if (str_to_find_len > str_len) {
return false;
}
return (strncmp(str + (str_len - str_to_find_len), str_to_find, str_to_find_len) == 0);
}
// Used to obtain the package name from a fully qualified class name.
// It is the responsibility of the caller to establish a ResourceMark.
const char* ClassLoader::package_from_name(const char* const class_name, bool* bad_class_name) {
if (class_name == NULL) {
if (bad_class_name != NULL) {
*bad_class_name = true;
}
return NULL;
}
if (bad_class_name != NULL) {
*bad_class_name = false;
}
const char* const last_slash = strrchr(class_name, JVM_SIGNATURE_SLASH);
if (last_slash == NULL) {
// No package name
return NULL;
}
char* class_name_ptr = (char*) class_name;
// Skip over '['s
if (*class_name_ptr == JVM_SIGNATURE_ARRAY) {
do {
class_name_ptr++;
} while (*class_name_ptr == JVM_SIGNATURE_ARRAY);
// Fully qualified class names should not contain a 'L'.
// Set bad_class_name to true to indicate that the package name
// could not be obtained due to an error condition.
// In this situation, is_same_class_package returns false.
if (*class_name_ptr == JVM_SIGNATURE_CLASS) {
if (bad_class_name != NULL) {
*bad_class_name = true;
}
return NULL;
}
}
int length = last_slash - class_name_ptr;
// A class name could have just the slash character in the name.
if (length <= 0) {
// No package name
if (bad_class_name != NULL) {
*bad_class_name = true;
}
return NULL;
}
// drop name after last slash (including slash)
// Ex., "java/lang/String.class" => "java/lang"
char* pkg_name = NEW_RESOURCE_ARRAY(char, length + 1);
strncpy(pkg_name, class_name_ptr, length);
*(pkg_name+length) = '\0';
return (const char *)pkg_name;
}
// Given a fully qualified class name, find its defining package in the class loader's
// package entry table.
PackageEntry* ClassLoader::get_package_entry(const char* class_name, ClassLoaderData* loader_data, TRAPS) {
ResourceMark rm(THREAD);
const char *pkg_name = ClassLoader::package_from_name(class_name);
if (pkg_name == NULL) {
return NULL;
}
PackageEntryTable* pkgEntryTable = loader_data->packages();
TempNewSymbol pkg_symbol = SymbolTable::new_symbol(pkg_name);
return pkgEntryTable->lookup_only(pkg_symbol);
}
const char* ClassPathEntry::copy_path(const char* path) {
char* copy = NEW_C_HEAP_ARRAY(char, strlen(path)+1, mtClass);
strcpy(copy, path);
return copy;
}
ClassFileStream* ClassPathDirEntry::open_stream(const char* name, TRAPS) {
// construct full path name
assert((_dir != NULL) && (name != NULL), "sanity");
size_t path_len = strlen(_dir) + strlen(name) + strlen(os::file_separator()) + 1;
char* path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, path_len);
int len = jio_snprintf(path, path_len, "%s%s%s", _dir, os::file_separator(), name);
assert(len == (int)(path_len - 1), "sanity");
// check if file exists
struct stat st;
if (os::stat(path, &st) == 0) {
// found file, open it
int file_handle = os::open(path, 0, 0);
if (file_handle != -1) {
// read contents into resource array
u1* buffer = NEW_RESOURCE_ARRAY(u1, st.st_size);
size_t num_read = os::read(file_handle, (char*) buffer, st.st_size);
// close file
os::close(file_handle);
// construct ClassFileStream
if (num_read == (size_t)st.st_size) {
if (UsePerfData) {
ClassLoader::perf_sys_classfile_bytes_read()->inc(num_read);
}
FREE_RESOURCE_ARRAY(char, path, path_len);
// Resource allocated
return new ClassFileStream(buffer,
st.st_size,
_dir,
ClassFileStream::verify);
}
}
}
FREE_RESOURCE_ARRAY(char, path, path_len);
return NULL;
}
ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name,
bool is_boot_append, bool from_class_path_attr) : ClassPathEntry() {
_zip = zip;
_zip_name = copy_path(zip_name);
_from_class_path_attr = from_class_path_attr;
}
ClassPathZipEntry::~ClassPathZipEntry() {
(*ZipClose)(_zip);
FREE_C_HEAP_ARRAY(char, _zip_name);
}
u1* ClassPathZipEntry::open_entry(const char* name, jint* filesize, bool nul_terminate, TRAPS) {
// enable call to C land
JavaThread* thread = JavaThread::current();
ThreadToNativeFromVM ttn(thread);
// check whether zip archive contains name
jint name_len;
jzentry* entry = (*FindEntry)(_zip, name, filesize, &name_len);
if (entry == NULL) return NULL;
u1* buffer;
char name_buf[128];
char* filename;
if (name_len < 128) {
filename = name_buf;
} else {
filename = NEW_RESOURCE_ARRAY(char, name_len + 1);
}
// read contents into resource array
int size = (*filesize) + ((nul_terminate) ? 1 : 0);
buffer = NEW_RESOURCE_ARRAY(u1, size);
if (!(*ReadEntry)(_zip, entry, buffer, filename)) return NULL;
// return result
if (nul_terminate) {
buffer[*filesize] = 0;
}
return buffer;
}
ClassFileStream* ClassPathZipEntry::open_stream(const char* name, TRAPS) {
jint filesize;
u1* buffer = open_entry(name, &filesize, false, CHECK_NULL);
if (buffer == NULL) {
return NULL;
}
if (UsePerfData) {
ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
}
// Resource allocated
return new ClassFileStream(buffer,
filesize,
_zip_name,
ClassFileStream::verify);
}
// invoke function for each entry in the zip file
void ClassPathZipEntry::contents_do(void f(const char* name, void* context), void* context) {
JavaThread* thread = JavaThread::current();
HandleMark handle_mark(thread);
ThreadToNativeFromVM ttn(thread);
for (int n = 0; ; n++) {
jzentry * ze = ((*GetNextEntry)(_zip, n));
if (ze == NULL) break;
(*f)(ze->name, context);
}
}
DEBUG_ONLY(ClassPathImageEntry* ClassPathImageEntry::_singleton = NULL;)
void ClassPathImageEntry::close_jimage() {
if (_jimage != NULL) {
(*JImageClose)(_jimage);
_jimage = NULL;
}
}
ClassPathImageEntry::ClassPathImageEntry(JImageFile* jimage, const char* name) :
ClassPathEntry(),
_jimage(jimage) {
guarantee(jimage != NULL, "jimage file is null");
guarantee(name != NULL, "jimage file name is null");
assert(_singleton == NULL, "VM supports only one jimage");
DEBUG_ONLY(_singleton = this);
size_t len = strlen(name) + 1;
_name = copy_path(name);
}
ClassPathImageEntry::~ClassPathImageEntry() {
assert(_singleton == this, "must be");
DEBUG_ONLY(_singleton = NULL);
FREE_C_HEAP_ARRAY(const char, _name);
if (_jimage != NULL) {
(*JImageClose)(_jimage);
_jimage = NULL;
}
}
ClassFileStream* ClassPathImageEntry::open_stream(const char* name, TRAPS) {
return open_stream_for_loader(name, ClassLoaderData::the_null_class_loader_data(), THREAD);
}
// For a class in a named module, look it up in the jimage file using this syntax:
// /<module-name>/<package-name>/<base-class>
//
// Assumptions:
// 1. There are no unnamed modules in the jimage file.
// 2. A package is in at most one module in the jimage file.
//
ClassFileStream* ClassPathImageEntry::open_stream_for_loader(const char* name, ClassLoaderData* loader_data, TRAPS) {
jlong size;
JImageLocationRef location = (*JImageFindResource)(_jimage, "", get_jimage_version_string(), name, &size);
if (location == 0) {
ResourceMark rm;
const char* pkg_name = ClassLoader::package_from_name(name);
if (pkg_name != NULL) {
if (!Universe::is_module_initialized()) {
location = (*JImageFindResource)(_jimage, JAVA_BASE_NAME, get_jimage_version_string(), name, &size);
} else {
PackageEntry* package_entry = ClassLoader::get_package_entry(name, loader_data, CHECK_NULL);
if (package_entry != NULL) {
ResourceMark rm;
// Get the module name
ModuleEntry* module = package_entry->module();
assert(module != NULL, "Boot classLoader package missing module");
assert(module->is_named(), "Boot classLoader package is in unnamed module");
const char* module_name = module->name()->as_C_string();
if (module_name != NULL) {
location = (*JImageFindResource)(_jimage, module_name, get_jimage_version_string(), name, &size);
}
}
}
}
}
if (location != 0) {
if (UsePerfData) {
ClassLoader::perf_sys_classfile_bytes_read()->inc(size);
}
char* data = NEW_RESOURCE_ARRAY(char, size);
(*JImageGetResource)(_jimage, location, data, size);
// Resource allocated
assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be");
return new ClassFileStream((u1*)data,
(int)size,
_name,
ClassFileStream::verify,
true); // from_boot_loader_modules_image
}
return NULL;
}
JImageLocationRef ClassLoader::jimage_find_resource(JImageFile* jf,
const char* module_name,
const char* file_name,
jlong &size) {
return ((*JImageFindResource)(jf, module_name, get_jimage_version_string(), file_name, &size));
}
bool ClassPathImageEntry::is_modules_image() const {
assert(this == _singleton, "VM supports a single jimage");
assert(this == (ClassPathImageEntry*)ClassLoader::get_jrt_entry(), "must be used for jrt entry");
return true;
}
#if INCLUDE_CDS
void ClassLoader::exit_with_path_failure(const char* error, const char* message) {
Arguments::assert_is_dumping_archive();
tty->print_cr("Hint: enable -Xlog:class+path=info to diagnose the failure");
vm_exit_during_initialization(error, message);
}
#endif
ModuleClassPathList::ModuleClassPathList(Symbol* module_name) {
_module_name = module_name;
_module_first_entry = NULL;
_module_last_entry = NULL;
}
ModuleClassPathList::~ModuleClassPathList() {
// Clean out each ClassPathEntry on list
ClassPathEntry* e = _module_first_entry;
while (e != NULL) {
ClassPathEntry* next_entry = e->next();
delete e;
e = next_entry;
}
}
void ModuleClassPathList::add_to_list(ClassPathEntry* new_entry) {
if (new_entry != NULL) {
if (_module_last_entry == NULL) {
_module_first_entry = _module_last_entry = new_entry;
} else {
_module_last_entry->set_next(new_entry);
_module_last_entry = new_entry;
}
}
}
void ClassLoader::trace_class_path(const char* msg, const char* name) {
LogTarget(Info, class, path) lt;
if (lt.is_enabled()) {
LogStream ls(lt);
if (msg) {
ls.print("%s", msg);
}
if (name) {
if (strlen(name) < 256) {
ls.print("%s", name);
} else {
// For very long paths, we need to print each character separately,
// as print_cr() has a length limit
while (name[0] != '\0') {
ls.print("%c", name[0]);
name++;
}
}
}
ls.cr();
}
}
void ClassLoader::setup_bootstrap_search_path() {
const char* sys_class_path = Arguments::get_sysclasspath();
assert(sys_class_path != NULL, "System boot class path must not be NULL");
if (PrintSharedArchiveAndExit) {
// Don't print sys_class_path - this is the bootcp of this current VM process, not necessarily
// the same as the bootcp of the shared archive.
} else {
trace_class_path("bootstrap loader class path=", sys_class_path);
}
setup_boot_search_path(sys_class_path);
}
#if INCLUDE_CDS
void ClassLoader::setup_app_search_path(const char *class_path) {
Arguments::assert_is_dumping_archive();
ResourceMark rm;
ClasspathStream cp_stream(class_path);
while (cp_stream.has_next()) {
const char* path = cp_stream.get_next();
update_class_path_entry_list(path, false, false, false);
}
}
void ClassLoader::add_to_module_path_entries(const char* path,
ClassPathEntry* entry) {
assert(entry != NULL, "ClassPathEntry should not be NULL");
Arguments::assert_is_dumping_archive();
// The entry does not exist, add to the list
if (_module_path_entries == NULL) {
assert(_last_module_path_entry == NULL, "Sanity");
_module_path_entries = _last_module_path_entry = entry;
} else {
_last_module_path_entry->set_next(entry);
_last_module_path_entry = entry;
}
}
// Add a module path to the _module_path_entries list.
void ClassLoader::update_module_path_entry_list(const char *path, TRAPS) {
Arguments::assert_is_dumping_archive();
struct stat st;
if (os::stat(path, &st) != 0) {
tty->print_cr("os::stat error %d (%s). CDS dump aborted (path was \"%s\").",
errno, os::errno_name(errno), path);
vm_exit_during_initialization();
}
// File or directory found
ClassPathEntry* new_entry = NULL;
new_entry = create_class_path_entry(path, &st, true /* throw_exception */,
false /*is_boot_append */, false /* from_class_path_attr */, CHECK);
if (new_entry == NULL) {
return;
}
add_to_module_path_entries(path, new_entry);
return;
}
void ClassLoader::setup_module_search_path(const char* path, TRAPS) {
update_module_path_entry_list(path, THREAD);
}
#endif // INCLUDE_CDS
void ClassLoader::close_jrt_image() {
// Not applicable for exploded builds
if (!ClassLoader::has_jrt_entry()) return;
_jrt_entry->close_jimage();
}
// Construct the array of module/path pairs as specified to --patch-module
// for the boot loader to search ahead of the jimage, if the class being
// loaded is defined to a module that has been specified to --patch-module.
void ClassLoader::setup_patch_mod_entries() {
Thread* THREAD = Thread::current();
GrowableArray<ModulePatchPath*>* patch_mod_args = Arguments::get_patch_mod_prefix();
int num_of_entries = patch_mod_args->length();
// Set up the boot loader's _patch_mod_entries list
_patch_mod_entries = new (ResourceObj::C_HEAP, mtModule) GrowableArray<ModuleClassPathList*>(num_of_entries, true);
for (int i = 0; i < num_of_entries; i++) {
const char* module_name = (patch_mod_args->at(i))->module_name();
Symbol* const module_sym = SymbolTable::new_symbol(module_name);
assert(module_sym != NULL, "Failed to obtain Symbol for module name");
ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
char* class_path = (patch_mod_args->at(i))->path_string();
ResourceMark rm(THREAD);
ClasspathStream cp_stream(class_path);
while (cp_stream.has_next()) {
const char* path = cp_stream.get_next();
struct stat st;
if (os::stat(path, &st) == 0) {
// File or directory found
ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
// If the path specification is valid, enter it into this module's list
if (new_entry != NULL) {
module_cpl->add_to_list(new_entry);
}
}
}
// Record the module into the list of --patch-module entries only if
// valid ClassPathEntrys have been created
if (module_cpl->module_first_entry() != NULL) {
_patch_mod_entries->push(module_cpl);
}
}
}
// Determine whether the module has been patched via the command-line
// option --patch-module
bool ClassLoader::is_in_patch_mod_entries(Symbol* module_name) {
if (_patch_mod_entries != NULL && _patch_mod_entries->is_nonempty()) {
int table_len = _patch_mod_entries->length();
for (int i = 0; i < table_len; i++) {
ModuleClassPathList* patch_mod = _patch_mod_entries->at(i);
if (module_name->fast_compare(patch_mod->module_name()) == 0) {
return true;
}
}
}
return false;
}
// Set up the _jrt_entry if present and boot append path
void ClassLoader::setup_boot_search_path(const char *class_path) {
EXCEPTION_MARK;
ResourceMark rm(THREAD);
ClasspathStream cp_stream(class_path);
bool set_base_piece = true;
#if INCLUDE_CDS
if (Arguments::is_dumping_archive()) {
if (!Arguments::has_jimage()) {
vm_exit_during_initialization("CDS is not supported in exploded JDK build", NULL);
}
}
#endif
while (cp_stream.has_next()) {
const char* path = cp_stream.get_next();
if (set_base_piece) {
// The first time through the bootstrap_search setup, it must be determined
// what the base or core piece of the boot loader search is. Either a java runtime
// image is present or this is an exploded module build situation.
assert(string_ends_with(path, MODULES_IMAGE_NAME) || string_ends_with(path, JAVA_BASE_NAME),
"Incorrect boot loader search path, no java runtime image or " JAVA_BASE_NAME " exploded build");
struct stat st;
if (os::stat(path, &st) == 0) {
// Directory found
ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
// Check for a jimage
if (Arguments::has_jimage()) {
assert(_jrt_entry == NULL, "should not setup bootstrap class search path twice");
_jrt_entry = new_entry;
assert(new_entry != NULL && new_entry->is_modules_image(), "No java runtime image present");
assert(_jrt_entry->jimage() != NULL, "No java runtime image");
}
} else {
// If path does not exist, exit
vm_exit_during_initialization("Unable to establish the boot loader search path", path);
}
set_base_piece = false;
} else {
// Every entry on the system boot class path after the initial base piece,
// which is set by os::set_boot_path(), is considered an appended entry.
update_class_path_entry_list(path, false, true, false);
}
}
}
// During an exploded modules build, each module defined to the boot loader
// will be added to the ClassLoader::_exploded_entries array.
void ClassLoader::add_to_exploded_build_list(Symbol* module_sym, TRAPS) {
assert(!ClassLoader::has_jrt_entry(), "Exploded build not applicable");
assert(_exploded_entries != NULL, "_exploded_entries was not initialized");
// Find the module's symbol
ResourceMark rm(THREAD);
const char *module_name = module_sym->as_C_string();
const char *home = Arguments::get_java_home();
const char file_sep = os::file_separator()[0];
// 10 represents the length of "modules" + 2 file separators + \0
size_t len = strlen(home) + strlen(module_name) + 10;
char *path = NEW_RESOURCE_ARRAY(char, len);
jio_snprintf(path, len, "%s%cmodules%c%s", home, file_sep, file_sep, module_name);
struct stat st;
if (os::stat(path, &st) == 0) {
// Directory found
ClassPathEntry* new_entry = create_class_path_entry(path, &st, false, false, false, CHECK);
// If the path specification is valid, enter it into this module's list.
// There is no need to check for duplicate modules in the exploded entry list,
// since no two modules with the same name can be defined to the boot loader.
// This is checked at module definition time in Modules::define_module.
if (new_entry != NULL) {
ModuleClassPathList* module_cpl = new ModuleClassPathList(module_sym);
module_cpl->add_to_list(new_entry);
{
MutexLocker ml(Module_lock, THREAD);
_exploded_entries->push(module_cpl);
}
log_info(class, load)("path: %s", path);
}
}
}
ClassPathEntry* ClassLoader::create_class_path_entry(const char *path, const struct stat* st,
bool throw_exception,
bool is_boot_append,
bool from_class_path_attr,
TRAPS) {
JavaThread* thread = JavaThread::current();
ClassPathEntry* new_entry = NULL;
if ((st->st_mode & S_IFMT) == S_IFREG) {
ResourceMark rm(thread);
// Regular file, should be a zip or jimage file
// Canonicalized filename
char* canonical_path = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, JVM_MAXPATHLEN);
if (!get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
// This matches the classic VM
if (throw_exception) {
THROW_MSG_(vmSymbols::java_io_IOException(), "Bad pathname", NULL);
} else {
return NULL;
}
}
jint error;
JImageFile* jimage =(*JImageOpen)(canonical_path, &error);
if (jimage != NULL) {
new_entry = new ClassPathImageEntry(jimage, canonical_path);
} else {
char* error_msg = NULL;
jzfile* zip;
{
// enable call to C land
ThreadToNativeFromVM ttn(thread);
HandleMark hm(thread);
zip = (*ZipOpen)(canonical_path, &error_msg);
}
if (zip != NULL && error_msg == NULL) {
new_entry = new ClassPathZipEntry(zip, path, is_boot_append, from_class_path_attr);
} else {
char *msg;
if (error_msg == NULL) {
msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, strlen(path) + 128); ;
jio_snprintf(msg, strlen(path) + 127, "error in opening JAR file %s", path);
} else {
int len = (int)(strlen(path) + strlen(error_msg) + 128);
msg = NEW_RESOURCE_ARRAY_IN_THREAD(thread, char, len); ;
jio_snprintf(msg, len - 1, "error in opening JAR file <%s> %s", error_msg, path);
}
// Don't complain about bad jar files added via -Xbootclasspath/a:.
if (throw_exception && is_init_completed()) {
THROW_MSG_(vmSymbols::java_lang_ClassNotFoundException(), msg, NULL);
} else {
return NULL;
}
}
}
log_info(class, path)("opened: %s", path);
log_info(class, load)("opened: %s", path);
} else {
// Directory
new_entry = new ClassPathDirEntry(path);
log_info(class, load)("path: %s", path);
}
return new_entry;
}
// Create a class path zip entry for a given path (return NULL if not found
// or zip/JAR file cannot be opened)
ClassPathZipEntry* ClassLoader::create_class_path_zip_entry(const char *path, bool is_boot_append) {
// check for a regular file
struct stat st;
if (os::stat(path, &st) == 0) {
if ((st.st_mode & S_IFMT) == S_IFREG) {
char canonical_path[JVM_MAXPATHLEN];
if (get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
char* error_msg = NULL;
jzfile* zip;
{
// enable call to C land
JavaThread* thread = JavaThread::current();
ThreadToNativeFromVM ttn(thread);
HandleMark hm(thread);
zip = (*ZipOpen)(canonical_path, &error_msg);
}
if (zip != NULL && error_msg == NULL) {
// create using canonical path
return new ClassPathZipEntry(zip, canonical_path, is_boot_append, false);
}
}
}
}
return NULL;
}
// returns true if entry already on class path
bool ClassLoader::contains_append_entry(const char* name) {
ClassPathEntry* e = _first_append_entry;
while (e != NULL) {
// assume zip entries have been canonicalized
if (strcmp(name, e->name()) == 0) {
return true;
}
e = e->next();
}
return false;
}
void ClassLoader::add_to_boot_append_entries(ClassPathEntry *new_entry) {
if (new_entry != NULL) {
if (_last_append_entry == NULL) {
assert(_first_append_entry == NULL, "boot loader's append class path entry list not empty");
_first_append_entry = _last_append_entry = new_entry;
} else {
_last_append_entry->set_next(new_entry);
_last_append_entry = new_entry;
}
}
}
// Record the path entries specified in -cp during dump time. The recorded
// information will be used at runtime for loading the archived app classes.
//
// Note that at dump time, ClassLoader::_app_classpath_entries are NOT used for
// loading app classes. Instead, the app class are loaded by the
// jdk/internal/loader/ClassLoaders$AppClassLoader instance.
void ClassLoader::add_to_app_classpath_entries(const char* path,
ClassPathEntry* entry,
bool check_for_duplicates) {
#if INCLUDE_CDS
assert(entry != NULL, "ClassPathEntry should not be NULL");
ClassPathEntry* e = _app_classpath_entries;
if (check_for_duplicates) {
while (e != NULL) {
if (strcmp(e->name(), entry->name()) == 0) {
// entry already exists
return;
}
e = e->next();
}
}
// The entry does not exist, add to the list
if (_app_classpath_entries == NULL) {
assert(_last_app_classpath_entry == NULL, "Sanity");
_app_classpath_entries = _last_app_classpath_entry = entry;
} else {
_last_app_classpath_entry->set_next(entry);
_last_app_classpath_entry = entry;
}
if (entry->is_jar_file()) {
ClassLoaderExt::process_jar_manifest(entry, check_for_duplicates);
}
#endif
}
// Returns true IFF the file/dir exists and the entry was successfully created.
bool ClassLoader::update_class_path_entry_list(const char *path,
bool check_for_duplicates,
bool is_boot_append,
bool from_class_path_attr,
bool throw_exception) {
struct stat st;
if (os::stat(path, &st) == 0) {
// File or directory found
ClassPathEntry* new_entry = NULL;
Thread* THREAD = Thread::current();
new_entry = create_class_path_entry(path, &st, throw_exception, is_boot_append, from_class_path_attr, CHECK_(false));
if (new_entry == NULL) {
return false;
}
// Do not reorder the bootclasspath which would break get_system_package().
// Add new entry to linked list
if (is_boot_append) {
add_to_boot_append_entries(new_entry);
} else {
add_to_app_classpath_entries(path, new_entry, check_for_duplicates);
}
return true;
} else {
return false;
}
}
static void print_module_entry_table(const GrowableArray<ModuleClassPathList*>* const module_list) {
ResourceMark rm;
int num_of_entries = module_list->length();
for (int i = 0; i < num_of_entries; i++) {
ClassPathEntry* e;
ModuleClassPathList* mpl = module_list->at(i);
tty->print("%s=", mpl->module_name()->as_C_string());
e = mpl->module_first_entry();
while (e != NULL) {
tty->print("%s", e->name());
e = e->next();
if (e != NULL) {
tty->print("%s", os::path_separator());
}
}
tty->print(" ;");
}
}
void ClassLoader::print_bootclasspath() {
ClassPathEntry* e;
tty->print("[bootclasspath= ");
// Print --patch-module module/path specifications first
if (_patch_mod_entries != NULL) {
print_module_entry_table(_patch_mod_entries);
}
// [jimage | exploded modules build]
if (has_jrt_entry()) {
// Print the location of the java runtime image
tty->print("%s ;", _jrt_entry->name());
} else {
// Print exploded module build path specifications
if (_exploded_entries != NULL) {
print_module_entry_table(_exploded_entries);
}
}
// appended entries
e = _first_append_entry;
while (e != NULL) {
tty->print("%s ;", e->name());
e = e->next();
}
tty->print_cr("]");
}
void* ClassLoader::dll_lookup(void* lib, const char* name, const char* path) {
void* func = os::dll_lookup(lib, name);
if (func == NULL) {
char msg[256] = "";
jio_snprintf(msg, sizeof(msg), "Could not resolve \"%s\"", name);
vm_exit_during_initialization(msg, path);
}
return func;
}
void ClassLoader::load_java_library() {
assert(CanonicalizeEntry == NULL, "should not load java library twice");
void *javalib_handle = os::native_java_library();
if (javalib_handle == NULL) {
vm_exit_during_initialization("Unable to load java library", NULL);
}
CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, dll_lookup(javalib_handle, "JDK_Canonicalize", NULL));
}
void ClassLoader::load_zip_library() {
assert(ZipOpen == NULL, "should not load zip library twice");
char path[JVM_MAXPATHLEN];
char ebuf[1024];
void* handle = NULL;
if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "zip")) {
handle = os::dll_load(path, ebuf, sizeof ebuf);
}
if (handle == NULL) {
vm_exit_during_initialization("Unable to load zip library", path);
}
ZipOpen = CAST_TO_FN_PTR(ZipOpen_t, dll_lookup(handle, "ZIP_Open", path));
ZipClose = CAST_TO_FN_PTR(ZipClose_t, dll_lookup(handle, "ZIP_Close", path));
FindEntry = CAST_TO_FN_PTR(FindEntry_t, dll_lookup(handle, "ZIP_FindEntry", path));
ReadEntry = CAST_TO_FN_PTR(ReadEntry_t, dll_lookup(handle, "ZIP_ReadEntry", path));
GetNextEntry = CAST_TO_FN_PTR(GetNextEntry_t, dll_lookup(handle, "ZIP_GetNextEntry", path));
Crc32 = CAST_TO_FN_PTR(Crc32_t, dll_lookup(handle, "ZIP_CRC32", path));
}
void ClassLoader::load_jimage_library() {
assert(JImageOpen == NULL, "should not load jimage library twice");
char path[JVM_MAXPATHLEN];
char ebuf[1024];
void* handle = NULL;
if (os::dll_locate_lib(path, sizeof(path), Arguments::get_dll_dir(), "jimage")) {
handle = os::dll_load(path, ebuf, sizeof ebuf);
}
if (handle == NULL) {
vm_exit_during_initialization("Unable to load jimage library", path);
}
JImageOpen = CAST_TO_FN_PTR(JImageOpen_t, dll_lookup(handle, "JIMAGE_Open", path));
JImageClose = CAST_TO_FN_PTR(JImageClose_t, dll_lookup(handle, "JIMAGE_Close", path));
JImagePackageToModule = CAST_TO_FN_PTR(JImagePackageToModule_t, dll_lookup(handle, "JIMAGE_PackageToModule", path));
JImageFindResource = CAST_TO_FN_PTR(JImageFindResource_t, dll_lookup(handle, "JIMAGE_FindResource", path));
JImageGetResource = CAST_TO_FN_PTR(JImageGetResource_t, dll_lookup(handle, "JIMAGE_GetResource", path));
JImageResourceIterator = CAST_TO_FN_PTR(JImageResourceIterator_t, dll_lookup(handle, "JIMAGE_ResourceIterator", path));
}
int ClassLoader::crc32(int crc, const char* buf, int len) {
return (*Crc32)(crc, (const jbyte*)buf, len);
}
// Function add_package extracts the package from the fully qualified class name
// and checks if the package is in the boot loader's package entry table. If so,
// then it sets the classpath_index in the package entry record.
//
// The classpath_index field is used to find the entry on the boot loader class
// path for packages with classes loaded by the boot loader from -Xbootclasspath/a
// in an unnamed module. It is also used to indicate (for all packages whose
// classes are loaded by the boot loader) that at least one of the package's
// classes has been loaded.
bool ClassLoader::add_package(const char *fullq_class_name, s2 classpath_index, TRAPS) {
assert(fullq_class_name != NULL, "just checking");
// Get package name from fully qualified class name.
ResourceMark rm(THREAD);
const char *cp = package_from_name(fullq_class_name);
if (cp != NULL) {
PackageEntryTable* pkg_entry_tbl = ClassLoaderData::the_null_class_loader_data()->packages();
TempNewSymbol pkg_symbol = SymbolTable::new_symbol(cp);
PackageEntry* pkg_entry = pkg_entry_tbl->lookup_only(pkg_symbol);
if (pkg_entry != NULL) {
assert(classpath_index != -1, "Unexpected classpath_index");
pkg_entry->set_classpath_index(classpath_index);
} else {
return false;
}
}
return true;
}
oop ClassLoader::get_system_package(const char* name, TRAPS) {
// Look up the name in the boot loader's package entry table.
if (name != NULL) {
TempNewSymbol package_sym = SymbolTable::new_symbol(name);
// Look for the package entry in the boot loader's package entry table.
PackageEntry* package =
ClassLoaderData::the_null_class_loader_data()->packages()->lookup_only(package_sym);
// Return NULL if package does not exist or if no classes in that package
// have been loaded.
if (package != NULL && package->has_loaded_class()) {
ModuleEntry* module = package->module();
if (module->location() != NULL) {
ResourceMark rm(THREAD);
Handle ml = java_lang_String::create_from_str(
module->location()->as_C_string(), THREAD);
return ml();
}
// Return entry on boot loader class path.
Handle cph = java_lang_String::create_from_str(
ClassLoader::classpath_entry(package->classpath_index())->name(), THREAD);
return cph();
}
}
return NULL;
}
objArrayOop ClassLoader::get_system_packages(TRAPS) {
ResourceMark rm(THREAD);
// List of pointers to PackageEntrys that have loaded classes.
GrowableArray<PackageEntry*>* loaded_class_pkgs = new GrowableArray<PackageEntry*>(50);
{
MutexLocker ml(Module_lock, THREAD);
PackageEntryTable* pe_table =
ClassLoaderData::the_null_class_loader_data()->packages();
// Collect the packages that have at least one loaded class.
for (int x = 0; x < pe_table->table_size(); x++) {
for (PackageEntry* package_entry = pe_table->bucket(x);
package_entry != NULL;
package_entry = package_entry->next()) {
if (package_entry->has_loaded_class()) {
loaded_class_pkgs->append(package_entry);
}
}
}
}
// Allocate objArray and fill with java.lang.String
objArrayOop r = oopFactory::new_objArray(SystemDictionary::String_klass(),
loaded_class_pkgs->length(), CHECK_NULL);
objArrayHandle result(THREAD, r);
for (int x = 0; x < loaded_class_pkgs->length(); x++) {
PackageEntry* package_entry = loaded_class_pkgs->at(x);
Handle str = java_lang_String::create_from_symbol(package_entry->name(), CHECK_NULL);
result->obj_at_put(x, str());
}
return result();
}
// caller needs ResourceMark
const char* ClassLoader::file_name_for_class_name(const char* class_name,
int class_name_len) {
assert(class_name != NULL, "invariant");
assert((int)strlen(class_name) == class_name_len, "invariant");
static const char class_suffix[] = ".class";
size_t class_suffix_len = sizeof(class_suffix);
char* const file_name = NEW_RESOURCE_ARRAY(char,
class_name_len +
class_suffix_len); // includes term NULL
strncpy(file_name, class_name, class_name_len);
strncpy(&file_name[class_name_len], class_suffix, class_suffix_len);
return file_name;
}
ClassPathEntry* find_first_module_cpe(ModuleEntry* mod_entry,
const GrowableArray<ModuleClassPathList*>* const module_list) {
int num_of_entries = module_list->length();
const Symbol* class_module_name = mod_entry->name();
// Loop through all the modules in either the patch-module or exploded entries looking for module
for (int i = 0; i < num_of_entries; i++) {
ModuleClassPathList* module_cpl = module_list->at(i);
Symbol* module_cpl_name = module_cpl->module_name();
if (module_cpl_name->fast_compare(class_module_name) == 0) {
// Class' module has been located.
return module_cpl->module_first_entry();
}
}
return NULL;
}
// Search either the patch-module or exploded build entries for class.
ClassFileStream* ClassLoader::search_module_entries(const GrowableArray<ModuleClassPathList*>* const module_list,
const char* const class_name,
const char* const file_name,
TRAPS) {
ClassFileStream* stream = NULL;
// Find the class' defining module in the boot loader's module entry table
PackageEntry* pkg_entry = get_package_entry(class_name, ClassLoaderData::the_null_class_loader_data(), CHECK_NULL);
ModuleEntry* mod_entry = (pkg_entry != NULL) ? pkg_entry->module() : NULL;
// If the module system has not defined java.base yet, then
// classes loaded are assumed to be defined to java.base.
// When java.base is eventually defined by the module system,
// all packages of classes that have been previously loaded
// are verified in ModuleEntryTable::verify_javabase_packages().
if (!Universe::is_module_initialized() &&
!ModuleEntryTable::javabase_defined() &&
mod_entry == NULL) {
mod_entry = ModuleEntryTable::javabase_moduleEntry();
}
// The module must be a named module
ClassPathEntry* e = NULL;
if (mod_entry != NULL && mod_entry->is_named()) {
if (module_list == _exploded_entries) {
// The exploded build entries can be added to at any time so a lock is
// needed when searching them.
assert(!ClassLoader::has_jrt_entry(), "Must be exploded build");
MutexLocker ml(Module_lock, THREAD);
e = find_first_module_cpe(mod_entry, module_list);
} else {
e = find_first_module_cpe(mod_entry, module_list);
}
}
// Try to load the class from the module's ClassPathEntry list.
while (e != NULL) {
stream = e->open_stream(file_name, CHECK_NULL);
// No context.check is required since CDS is not supported
// for an exploded modules build or if --patch-module is specified.
if (NULL != stream) {
return stream;
}
e = e->next();
}
// If the module was located, break out even if the class was not
// located successfully from that module's ClassPathEntry list.
// There will not be another valid entry for that module.
return NULL;
}
// Called by the boot classloader to load classes
InstanceKlass* ClassLoader::load_class(Symbol* name, bool search_append_only, TRAPS) {
assert(name != NULL, "invariant");
assert(THREAD->is_Java_thread(), "must be a JavaThread");
ResourceMark rm(THREAD);
HandleMark hm(THREAD);
const char* const class_name = name->as_C_string();
EventMark m("loading class %s", class_name);
const char* const file_name = file_name_for_class_name(class_name,
name->utf8_length());
assert(file_name != NULL, "invariant");
// Lookup stream for parsing .class file
ClassFileStream* stream = NULL;
s2 classpath_index = 0;
ClassPathEntry* e = NULL;
// If search_append_only is true, boot loader visibility boundaries are
// set to be _first_append_entry to the end. This includes:
// [-Xbootclasspath/a]; [jvmti appended entries]
//
// If search_append_only is false, boot loader visibility boundaries are
// set to be the --patch-module entries plus the base piece. This includes:
// [--patch-module=<module>=<file>(<pathsep><file>)*]; [jimage | exploded module build]
//
// Load Attempt #1: --patch-module
// Determine the class' defining module. If it appears in the _patch_mod_entries,
// attempt to load the class from those locations specific to the module.
// Specifications to --patch-module can contain a partial number of classes
// that are part of the overall module definition. So if a particular class is not
// found within its module specification, the search should continue to Load Attempt #2.
// Note: The --patch-module entries are never searched if the boot loader's
// visibility boundary is limited to only searching the append entries.
if (_patch_mod_entries != NULL && !search_append_only) {
// At CDS dump time, the --patch-module entries are ignored. That means a
// class is still loaded from the runtime image even if it might
// appear in the _patch_mod_entries. The runtime shared class visibility
// check will determine if a shared class is visible based on the runtime
// environemnt, including the runtime --patch-module setting.
//
// DynamicDumpSharedSpaces requires UseSharedSpaces to be enabled. Since --patch-module
// is not supported with UseSharedSpaces, it is not supported with DynamicDumpSharedSpaces.
assert(!DynamicDumpSharedSpaces, "sanity");
if (!DumpSharedSpaces) {
stream = search_module_entries(_patch_mod_entries, class_name, file_name, CHECK_NULL);
}
}
// Load Attempt #2: [jimage | exploded build]
if (!search_append_only && (NULL == stream)) {
if (has_jrt_entry()) {
e = _jrt_entry;
stream = _jrt_entry->open_stream(file_name, CHECK_NULL);
} else {
// Exploded build - attempt to locate class in its defining module's location.
assert(_exploded_entries != NULL, "No exploded build entries present");
stream = search_module_entries(_exploded_entries, class_name, file_name, CHECK_NULL);
}
}
// Load Attempt #3: [-Xbootclasspath/a]; [jvmti appended entries]
if (search_append_only && (NULL == stream)) {
// For the boot loader append path search, the starting classpath_index
// for the appended piece is always 1 to account for either the
// _jrt_entry or the _exploded_entries.
assert(classpath_index == 0, "The classpath_index has been incremented incorrectly");
classpath_index = 1;
e = _first_append_entry;
while (e != NULL) {
stream = e->open_stream(file_name, CHECK_NULL);
if (NULL != stream) {
break;
}
e = e->next();
++classpath_index;
}
}
if (NULL == stream) {
return NULL;
}
stream->set_verify(ClassLoaderExt::should_verify(classpath_index));
ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
Handle protection_domain;
InstanceKlass* result = KlassFactory::create_from_stream(stream,
name,
loader_data,
protection_domain,
NULL, // unsafe_anonymous_host
NULL, // cp_patches
THREAD);
if (HAS_PENDING_EXCEPTION) {
if (DumpSharedSpaces) {
log_error(cds)("Preload Error: Failed to load %s", class_name);
}
return NULL;
}
if (!add_package(file_name, classpath_index, THREAD)) {
return NULL;
}
return result;
}
#if INCLUDE_CDS
char* ClassLoader::skip_uri_protocol(char* source) {
if (strncmp(source, "file:", 5) == 0) {
// file: protocol path could start with file:/ or file:///
// locate the char after all the forward slashes
int offset = 5;
while (*(source + offset) == '/') {
offset++;
}
source += offset;
// for non-windows platforms, move back one char as the path begins with a '/'
#ifndef _WINDOWS
source -= 1;
#endif
} else if (strncmp(source, "jrt:/", 5) == 0) {
source += 5;
}
return source;
}
// Record the shared classpath index and loader type for classes loaded
// by the builtin loaders at dump time.
void ClassLoader::record_result(InstanceKlass* ik, const ClassFileStream* stream, TRAPS) {
Arguments::assert_is_dumping_archive();
assert(stream != NULL, "sanity");
if (ik->is_unsafe_anonymous()) {
// We do not archive unsafe anonymous classes.
return;
}
oop loader = ik->class_loader();
char* src = (char*)stream->source();
if (src == NULL) {
if (loader == NULL) {
// JFR classes
ik->set_shared_classpath_index(0);
ik->set_class_loader_type(ClassLoader::BOOT_LOADER);
}
return;
}
assert(has_jrt_entry(), "CDS dumping does not support exploded JDK build");
ResourceMark rm(THREAD);
int classpath_index = -1;
PackageEntry* pkg_entry = ik->package();
if (FileMapInfo::get_number_of_shared_paths() > 0) {
char* canonical_path_table_entry = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
// save the path from the file: protocol or the module name from the jrt: protocol
// if no protocol prefix is found, path is the same as stream->source()
char* path = skip_uri_protocol(src);
char* canonical_class_src_path = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, JVM_MAXPATHLEN);
bool success = get_canonical_path(path, canonical_class_src_path, JVM_MAXPATHLEN);
// The path is from the ClassFileStream. Since a ClassFileStream has been created successfully in functions
// such as ClassLoader::load_class(), its source path must be valid.
assert(success, "must be valid path");
for (int i = 0; i < FileMapInfo::get_number_of_shared_paths(); i++) {
SharedClassPathEntry* ent = FileMapInfo::shared_path(i);
success = get_canonical_path(ent->name(), canonical_path_table_entry, JVM_MAXPATHLEN);
// A shared path has been validated during its creation in ClassLoader::create_class_path_entry(),
// it must be valid here.
assert(success, "must be valid path");
// If the path (from the class stream source) is the same as the shared
// class or module path, then we have a match.
if (strcmp(canonical_path_table_entry, canonical_class_src_path) == 0) {
// NULL pkg_entry and pkg_entry in an unnamed module implies the class
// is from the -cp or boot loader append path which consists of -Xbootclasspath/a
// and jvmti appended entries.
if ((pkg_entry == NULL) || (pkg_entry->in_unnamed_module())) {
// Ensure the index is within the -cp range before assigning
// to the classpath_index.
if (SystemDictionary::is_system_class_loader(loader) &&
(i >= ClassLoaderExt::app_class_paths_start_index()) &&
(i < ClassLoaderExt::app_module_paths_start_index())) {
classpath_index = i;
break;
} else {
if ((i >= 1) &&
(i < ClassLoaderExt::app_class_paths_start_index())) {
// The class must be from boot loader append path which consists of
// -Xbootclasspath/a and jvmti appended entries.
assert(loader == NULL, "sanity");
classpath_index = i;
break;
}
}
} else {
// A class from a named module from the --module-path. Ensure the index is
// within the --module-path range before assigning to the classpath_index.
if ((pkg_entry != NULL) && !(pkg_entry->in_unnamed_module()) && (i > 0)) {
if (i >= ClassLoaderExt::app_module_paths_start_index() &&
i < FileMapInfo::get_number_of_shared_paths()) {
classpath_index = i;
break;
}
}
}
}
// for index 0 and the stream->source() is the modules image or has the jrt: protocol.
// The class must be from the runtime modules image.
if (i == 0 && (stream->from_boot_loader_modules_image() || string_starts_with(src, "jrt:"))) {
classpath_index = i;
break;
}
}
// No path entry found for this class. Must be a shared class loaded by the
// user defined classloader.
if (classpath_index < 0) {
assert(ik->shared_classpath_index() < 0, "Sanity");
ik->set_shared_classpath_index(UNREGISTERED_INDEX);
SystemDictionaryShared::set_shared_class_misc_info(ik, (ClassFileStream*)stream);
return;
}
} else {
// The shared path table is set up after module system initialization.
// The path table contains no entry before that. Any classes loaded prior
// to the setup of the shared path table must be from the modules image.
assert(stream->from_boot_loader_modules_image(), "stream must be loaded by boot loader from modules image");
assert(FileMapInfo::get_number_of_shared_paths() == 0, "shared path table must not have been setup");
classpath_index = 0;
}
const char* const class_name = ik->name()->as_C_string();
const char* const file_name = file_name_for_class_name(class_name,
ik->name()->utf8_length());
assert(file_name != NULL, "invariant");
ClassLoaderExt::record_result(classpath_index, ik, THREAD);
}
#endif // INCLUDE_CDS
// Initialize the class loader's access to methods in libzip. Parse and
// process the boot classpath into a list ClassPathEntry objects. Once
// this list has been created, it must not change order (see class PackageInfo)
// it can be appended to and is by jvmti and the kernel vm.
void ClassLoader::initialize() {
EXCEPTION_MARK;
if (UsePerfData) {
// jvmstat performance counters
NEWPERFTICKCOUNTER(_perf_accumulated_time, SUN_CLS, "time");
NEWPERFTICKCOUNTER(_perf_class_init_time, SUN_CLS, "classInitTime");
NEWPERFTICKCOUNTER(_perf_class_init_selftime, SUN_CLS, "classInitTime.self");
NEWPERFTICKCOUNTER(_perf_class_verify_time, SUN_CLS, "classVerifyTime");
NEWPERFTICKCOUNTER(_perf_class_verify_selftime, SUN_CLS, "classVerifyTime.self");
NEWPERFTICKCOUNTER(_perf_class_link_time, SUN_CLS, "classLinkedTime");
NEWPERFTICKCOUNTER(_perf_class_link_selftime, SUN_CLS, "classLinkedTime.self");
NEWPERFEVENTCOUNTER(_perf_classes_inited, SUN_CLS, "initializedClasses");
NEWPERFEVENTCOUNTER(_perf_classes_linked, SUN_CLS, "linkedClasses");
NEWPERFEVENTCOUNTER(_perf_classes_verified, SUN_CLS, "verifiedClasses");
NEWPERFTICKCOUNTER(_perf_class_parse_time, SUN_CLS, "parseClassTime");
NEWPERFTICKCOUNTER(_perf_class_parse_selftime, SUN_CLS, "parseClassTime.self");
NEWPERFTICKCOUNTER(_perf_sys_class_lookup_time, SUN_CLS, "lookupSysClassTime");
NEWPERFTICKCOUNTER(_perf_shared_classload_time, SUN_CLS, "sharedClassLoadTime");
NEWPERFTICKCOUNTER(_perf_sys_classload_time, SUN_CLS, "sysClassLoadTime");
NEWPERFTICKCOUNTER(_perf_app_classload_time, SUN_CLS, "appClassLoadTime");
NEWPERFTICKCOUNTER(_perf_app_classload_selftime, SUN_CLS, "appClassLoadTime.self");
NEWPERFEVENTCOUNTER(_perf_app_classload_count, SUN_CLS, "appClassLoadCount");
NEWPERFTICKCOUNTER(_perf_define_appclasses, SUN_CLS, "defineAppClasses");
NEWPERFTICKCOUNTER(_perf_define_appclass_time, SUN_CLS, "defineAppClassTime");
NEWPERFTICKCOUNTER(_perf_define_appclass_selftime, SUN_CLS, "defineAppClassTime.self");
NEWPERFBYTECOUNTER(_perf_app_classfile_bytes_read, SUN_CLS, "appClassBytes");
NEWPERFBYTECOUNTER(_perf_sys_classfile_bytes_read, SUN_CLS, "sysClassBytes");
// The following performance counters are added for measuring the impact
// of the bug fix of 6365597. They are mainly focused on finding out
// the behavior of system & user-defined classloader lock, whether
// ClassLoader.loadClass/findClass is being called synchronized or not.
NEWPERFEVENTCOUNTER(_sync_systemLoaderLockContentionRate, SUN_CLS,
"systemLoaderLockContentionRate");
NEWPERFEVENTCOUNTER(_sync_nonSystemLoaderLockContentionRate, SUN_CLS,
"nonSystemLoaderLockContentionRate");
NEWPERFEVENTCOUNTER(_sync_JVMFindLoadedClassLockFreeCounter, SUN_CLS,
"jvmFindLoadedClassNoLockCalls");
NEWPERFEVENTCOUNTER(_sync_JVMDefineClassLockFreeCounter, SUN_CLS,
"jvmDefineClassNoLockCalls");
NEWPERFEVENTCOUNTER(_sync_JNIDefineClassLockFreeCounter, SUN_CLS,
"jniDefineClassNoLockCalls");
NEWPERFEVENTCOUNTER(_unsafe_defineClassCallCounter, SUN_CLS,
"unsafeDefineClassCalls");
}
// lookup java library entry points
load_java_library();
// lookup zip library entry points
load_zip_library();
// jimage library entry points are loaded below, in lookup_vm_options
setup_bootstrap_search_path();
}
char* lookup_vm_resource(JImageFile *jimage, const char *jimage_version, const char *path) {
jlong size;
JImageLocationRef location = (*JImageFindResource)(jimage, "java.base", jimage_version, path, &size);
if (location == 0)
return NULL;
char *val = NEW_C_HEAP_ARRAY(char, size+1, mtClass);
(*JImageGetResource)(jimage, location, val, size);
val[size] = '\0';
return val;
}
// Lookup VM options embedded in the modules jimage file
char* ClassLoader::lookup_vm_options() {
jint error;
char modules_path[JVM_MAXPATHLEN];
const char* fileSep = os::file_separator();
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