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Java example source code file (classLoader.cpp)

This example Java source code file (classLoader.cpp) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

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cast_to_fn_ptr, classpathentry, compiletheworld, has_pending_exception, newperfeventcounter, newperftickcounter, null, packagehashtable, packageinfo, perfcounter, sun_cls, thread, traps, useperfdata

The classLoader.cpp Java example source code

/*
 * Copyright (c) 1997, 2013, 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 "classfile/classFileParser.hpp"
#include "classfile/classFileStream.hpp"
#include "classfile/classLoader.hpp"
#include "classfile/classLoaderData.inline.hpp"
#include "classfile/javaClasses.hpp"
#include "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "compiler/compileBroker.hpp"
#include "gc_interface/collectedHeap.inline.hpp"
#include "interpreter/bytecodeStream.hpp"
#include "interpreter/oopMapCache.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/generation.hpp"
#include "memory/oopFactory.hpp"
#include "memory/universe.inline.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/instanceRefKlass.hpp"
#include "oops/oop.inline.hpp"
#include "oops/symbol.hpp"
#include "prims/jvm_misc.hpp"
#include "runtime/arguments.hpp"
#include "runtime/compilationPolicy.hpp"
#include "runtime/fprofiler.hpp"
#include "runtime/handles.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/init.hpp"
#include "runtime/interfaceSupport.hpp"
#include "runtime/java.hpp"
#include "runtime/javaCalls.hpp"
#include "runtime/threadCritical.hpp"
#include "runtime/timer.hpp"
#include "services/management.hpp"
#include "services/threadService.hpp"
#include "utilities/events.hpp"
#include "utilities/hashtable.hpp"
#include "utilities/hashtable.inline.hpp"
#ifdef TARGET_OS_FAMILY_linux
# include "os_linux.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_solaris
# include "os_solaris.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_windows
# include "os_windows.inline.hpp"
#endif
#ifdef TARGET_OS_FAMILY_bsd
# include "os_bsd.inline.hpp"
#endif


// Entry points in zip.dll for loading zip/jar file entries

typedef void * * (JNICALL *ZipOpen_t)(const char *name, char **pmsg);
typedef void (JNICALL *ZipClose_t)(jzfile *zip);
typedef jzentry* (JNICALL *FindEntry_t)(jzfile *zip, const char *name, jint *sizeP, jint *nameLen);
typedef jboolean (JNICALL *ReadEntry_t)(jzfile *zip, jzentry *entry, unsigned char *buf, char *namebuf);
typedef jboolean (JNICALL *ReadMappedEntry_t)(jzfile *zip, jzentry *entry, unsigned char **buf, char *namebuf);
typedef jzentry* (JNICALL *GetNextEntry_t)(jzfile *zip, jint n);

static ZipOpen_t         ZipOpen            = NULL;
static ZipClose_t        ZipClose           = NULL;
static FindEntry_t       FindEntry          = NULL;
static ReadEntry_t       ReadEntry          = NULL;
static ReadMappedEntry_t ReadMappedEntry    = NULL;
static GetNextEntry_t    GetNextEntry       = NULL;
static canonicalize_fn_t CanonicalizeEntry  = 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;
PerfCounter*    ClassLoader::_isUnsyncloadClass = NULL;
PerfCounter*    ClassLoader::_load_instance_class_failCounter = NULL;

ClassPathEntry* ClassLoader::_first_entry         = NULL;
ClassPathEntry* ClassLoader::_last_entry          = NULL;
PackageHashtable* ClassLoader::_package_hash_table = NULL;

// 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);
}

bool 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);
}


MetaIndex::MetaIndex(char** meta_package_names, int num_meta_package_names) {
  if (num_meta_package_names == 0) {
    _meta_package_names = NULL;
    _num_meta_package_names = 0;
  } else {
    _meta_package_names = NEW_C_HEAP_ARRAY(char*, num_meta_package_names, mtClass);
    _num_meta_package_names = num_meta_package_names;
    memcpy(_meta_package_names, meta_package_names, num_meta_package_names * sizeof(char*));
  }
}


MetaIndex::~MetaIndex() {
  FREE_C_HEAP_ARRAY(char*, _meta_package_names, mtClass);
}


bool MetaIndex::may_contain(const char* class_name) {
  if ( _num_meta_package_names == 0) {
    return false;
  }
  size_t class_name_len = strlen(class_name);
  for (int i = 0; i < _num_meta_package_names; i++) {
    char* pkg = _meta_package_names[i];
    size_t pkg_len = strlen(pkg);
    size_t min_len = MIN2(class_name_len, pkg_len);
    if (!strncmp(class_name, pkg, min_len)) {
      return true;
    }
  }
  return false;
}


ClassPathEntry::ClassPathEntry() {
  set_next(NULL);
}


bool ClassPathEntry::is_lazy() {
  return false;
}

ClassPathDirEntry::ClassPathDirEntry(char* dir) : ClassPathEntry() {
  _dir = NEW_C_HEAP_ARRAY(char, strlen(dir)+1, mtClass);
  strcpy(_dir, dir);
}


ClassFileStream* ClassPathDirEntry::open_stream(const char* name, TRAPS) {
  // construct full path name
  char path[JVM_MAXPATHLEN];
  if (jio_snprintf(path, sizeof(path), "%s%s%s", _dir, os::file_separator(), name) == -1) {
    return NULL;
  }
  // 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);
        }
        return new ClassFileStream(buffer, st.st_size, _dir);    // Resource allocated
      }
    }
  }
  return NULL;
}


ClassPathZipEntry::ClassPathZipEntry(jzfile* zip, const char* zip_name) : ClassPathEntry() {
  _zip = zip;
  _zip_name = NEW_C_HEAP_ARRAY(char, strlen(zip_name)+1, mtClass);
  strcpy(_zip_name, zip_name);
}

ClassPathZipEntry::~ClassPathZipEntry() {
  if (ZipClose != NULL) {
    (*ZipClose)(_zip);
  }
  FREE_C_HEAP_ARRAY(char, _zip_name, mtClass);
}

ClassFileStream* ClassPathZipEntry::open_stream(const char* name, TRAPS) {
  // enable call to C land
  JavaThread* thread = JavaThread::current();
  ThreadToNativeFromVM ttn(thread);
  // check whether zip archive contains name
  jint filesize, 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);
  }

  // file found, get pointer to class in mmaped jar file.
  if (ReadMappedEntry == NULL ||
      !(*ReadMappedEntry)(_zip, entry, &buffer, filename)) {
      // mmaped access not available, perhaps due to compression,
      // read contents into resource array
      buffer     = NEW_RESOURCE_ARRAY(u1, filesize);
      if (!(*ReadEntry)(_zip, entry, buffer, filename)) return NULL;
  }
  if (UsePerfData) {
    ClassLoader::perf_sys_classfile_bytes_read()->inc(filesize);
  }
  // return result
  return new ClassFileStream(buffer, filesize, _zip_name);    // Resource allocated
}

// 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);
  }
}

LazyClassPathEntry::LazyClassPathEntry(char* path, const struct stat* st) : ClassPathEntry() {
  _path = strdup(path);
  _st = *st;
  _meta_index = NULL;
  _resolved_entry = NULL;
  _has_error = false;
}

bool LazyClassPathEntry::is_jar_file() {
  return ((_st.st_mode & S_IFREG) == S_IFREG);
}

ClassPathEntry* LazyClassPathEntry::resolve_entry(TRAPS) {
  if (_resolved_entry != NULL) {
    return (ClassPathEntry*) _resolved_entry;
  }
  ClassPathEntry* new_entry = NULL;
  new_entry = ClassLoader::create_class_path_entry(_path, &_st, false, CHECK_NULL);
  {
    ThreadCritical tc;
    if (_resolved_entry == NULL) {
      _resolved_entry = new_entry;
      return new_entry;
    }
  }
  assert(_resolved_entry != NULL, "bug in MT-safe resolution logic");
  delete new_entry;
  return (ClassPathEntry*) _resolved_entry;
}

ClassFileStream* LazyClassPathEntry::open_stream(const char* name, TRAPS) {
  if (_meta_index != NULL &&
      !_meta_index->may_contain(name)) {
    return NULL;
  }
  if (_has_error) {
    return NULL;
  }
  ClassPathEntry* cpe = resolve_entry(THREAD);
  if (cpe == NULL) {
    _has_error = true;
    return NULL;
  } else {
    return cpe->open_stream(name, THREAD);
  }
}

bool LazyClassPathEntry::is_lazy() {
  return true;
}

static void print_meta_index(LazyClassPathEntry* entry,
                             GrowableArray<char*>& meta_packages) {
  tty->print("[Meta index for %s=", entry->name());
  for (int i = 0; i < meta_packages.length(); i++) {
    if (i > 0) tty->print(" ");
    tty->print(meta_packages.at(i));
  }
  tty->print_cr("]");
}


void ClassLoader::setup_meta_index() {
  // Set up meta index which allows us to open boot jars lazily if
  // class data sharing is enabled
  const char* known_version = "% VERSION 2";
  char* meta_index_path = Arguments::get_meta_index_path();
  char* meta_index_dir  = Arguments::get_meta_index_dir();
  FILE* file = fopen(meta_index_path, "r");
  int line_no = 0;
  if (file != NULL) {
    ResourceMark rm;
    LazyClassPathEntry* cur_entry = NULL;
    GrowableArray<char*> boot_class_path_packages(10);
    char package_name[256];
    bool skipCurrentJar = false;
    while (fgets(package_name, sizeof(package_name), file) != NULL) {
      ++line_no;
      // Remove trailing newline
      package_name[strlen(package_name) - 1] = '\0';
      switch(package_name[0]) {
        case '%':
        {
          if ((line_no == 1) && (strcmp(package_name, known_version) != 0)) {
            if (TraceClassLoading && Verbose) {
              tty->print("[Unsupported meta index version]");
            }
            fclose(file);
            return;
          }
        }

        // These directives indicate jar files which contain only
        // classes, only non-classfile resources, or a combination of
        // the two. See src/share/classes/sun/misc/MetaIndex.java and
        // make/tools/MetaIndex/BuildMetaIndex.java in the J2SE
        // workspace.
        case '#':
        case '!':
        case '@':
        {
          // Hand off current packages to current lazy entry (if any)
          if ((cur_entry != NULL) &&
              (boot_class_path_packages.length() > 0)) {
            if (TraceClassLoading && Verbose) {
              print_meta_index(cur_entry, boot_class_path_packages);
            }
            MetaIndex* index = new MetaIndex(boot_class_path_packages.adr_at(0),
                                             boot_class_path_packages.length());
            cur_entry->set_meta_index(index);
          }
          cur_entry = NULL;
          boot_class_path_packages.clear();

          // Find lazy entry corresponding to this jar file
          for (ClassPathEntry* entry = _first_entry; entry != NULL; entry = entry->next()) {
            if (entry->is_lazy() &&
                string_starts_with(entry->name(), meta_index_dir) &&
                string_ends_with(entry->name(), &package_name[2])) {
              cur_entry = (LazyClassPathEntry*) entry;
              break;
            }
          }

          // If the first character is '@', it indicates the following jar
          // file is a resource only jar file in which case, we should skip
          // reading the subsequent entries since the resource loading is
          // totally handled by J2SE side.
          if (package_name[0] == '@') {
            if (cur_entry != NULL) {
              cur_entry->set_meta_index(new MetaIndex(NULL, 0));
            }
            cur_entry = NULL;
            skipCurrentJar = true;
          } else {
            skipCurrentJar = false;
          }

          break;
        }

        default:
        {
          if (!skipCurrentJar && cur_entry != NULL) {
            char* new_name = strdup(package_name);
            boot_class_path_packages.append(new_name);
          }
        }
      }
    }
    // Hand off current packages to current lazy entry (if any)
    if ((cur_entry != NULL) &&
        (boot_class_path_packages.length() > 0)) {
      if (TraceClassLoading && Verbose) {
        print_meta_index(cur_entry, boot_class_path_packages);
      }
      MetaIndex* index = new MetaIndex(boot_class_path_packages.adr_at(0),
                                       boot_class_path_packages.length());
      cur_entry->set_meta_index(index);
    }
    fclose(file);
  }
}

void ClassLoader::setup_bootstrap_search_path() {
  assert(_first_entry == NULL, "should not setup bootstrap class search path twice");
  char* sys_class_path = os::strdup(Arguments::get_sysclasspath());
  if (TraceClassLoading && Verbose) {
    tty->print_cr("[Bootstrap loader class path=%s]", sys_class_path);
  }

  int len = (int)strlen(sys_class_path);
  int end = 0;

  // Iterate over class path entries
  for (int start = 0; start < len; start = end) {
    while (sys_class_path[end] && sys_class_path[end] != os::path_separator()[0]) {
      end++;
    }
    char* path = NEW_C_HEAP_ARRAY(char, end-start+1, mtClass);
    strncpy(path, &sys_class_path[start], end-start);
    path[end-start] = '\0';
    update_class_path_entry_list(path, false);
    FREE_C_HEAP_ARRAY(char, path, mtClass);
    while (sys_class_path[end] == os::path_separator()[0]) {
      end++;
    }
  }
}

ClassPathEntry* ClassLoader::create_class_path_entry(char *path, const struct stat* st, bool lazy, TRAPS) {
  JavaThread* thread = JavaThread::current();
  if (lazy) {
    return new LazyClassPathEntry(path, st);
  }
  ClassPathEntry* new_entry = NULL;
  if ((st->st_mode & S_IFREG) == S_IFREG) {
    // Regular file, should be a zip file
    // Canonicalized filename
    char canonical_path[JVM_MAXPATHLEN];
    if (!get_canonical_path(path, canonical_path, JVM_MAXPATHLEN)) {
      // This matches the classic VM
      THROW_MSG_(vmSymbols::java_io_IOException(), "Bad pathname", NULL);
    }
    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);
      if (TraceClassLoading) {
        tty->print_cr("[Opened %s]", path);
      }
    } else {
      ResourceMark rm(thread);
      char *msg;
      if (error_msg == NULL) {
        msg = NEW_RESOURCE_ARRAY(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(char, len); ;
        jio_snprintf(msg, len - 1, "error in opening JAR file <%s> %s", error_msg, path);
      }
      THROW_MSG_(vmSymbols::java_lang_ClassNotFoundException(), msg, NULL);
    }
  } else {
    // Directory
    new_entry = new ClassPathDirEntry(path);
    if (TraceClassLoading) {
      tty->print_cr("[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) {
  // check for a regular file
  struct stat st;
  if (os::stat(path, &st) == 0) {
    if ((st.st_mode & S_IFREG) == S_IFREG) {
      char orig_path[JVM_MAXPATHLEN];
      char canonical_path[JVM_MAXPATHLEN];

      strcpy(orig_path, path);
      if (get_canonical_path(orig_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);
        }
      }
    }
  }
  return NULL;
}

// returns true if entry already on class path
bool ClassLoader::contains_entry(ClassPathEntry *entry) {
  ClassPathEntry* e = _first_entry;
  while (e != NULL) {
    // assume zip entries have been canonicalized
    if (strcmp(entry->name(), e->name()) == 0) {
      return true;
    }
    e = e->next();
  }
  return false;
}

void ClassLoader::add_to_list(ClassPathEntry *new_entry) {
  if (new_entry != NULL) {
    if (_last_entry == NULL) {
      _first_entry = _last_entry = new_entry;
    } else {
      _last_entry->set_next(new_entry);
      _last_entry = new_entry;
    }
  }
}

void ClassLoader::update_class_path_entry_list(char *path,
                                               bool check_for_duplicates) {
  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, LazyBootClassLoader, CHECK);
    // The kernel VM adds dynamically to the end of the classloader path and
    // doesn't reorder the bootclasspath which would break java.lang.Package
    // (see PackageInfo).
    // Add new entry to linked list
    if (!check_for_duplicates || !contains_entry(new_entry)) {
      add_to_list(new_entry);
    }
  }
}

void ClassLoader::print_bootclasspath() {
  ClassPathEntry* e = _first_entry;
  tty->print("[bootclasspath= ");
  while (e != NULL) {
    tty->print("%s ;", e->name());
    e = e->next();
  }
  tty->print_cr("]");
}

void ClassLoader::load_zip_library() {
  assert(ZipOpen == NULL, "should not load zip library twice");
  // First make sure native library is loaded
  os::native_java_library();
  // Load zip library
  char path[JVM_MAXPATHLEN];
  char ebuf[1024];
  void* handle = NULL;
  if (os::dll_build_name(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);
  }
  // Lookup zip entry points
  ZipOpen      = CAST_TO_FN_PTR(ZipOpen_t, os::dll_lookup(handle, "ZIP_Open"));
  ZipClose     = CAST_TO_FN_PTR(ZipClose_t, os::dll_lookup(handle, "ZIP_Close"));
  FindEntry    = CAST_TO_FN_PTR(FindEntry_t, os::dll_lookup(handle, "ZIP_FindEntry"));
  ReadEntry    = CAST_TO_FN_PTR(ReadEntry_t, os::dll_lookup(handle, "ZIP_ReadEntry"));
  ReadMappedEntry = CAST_TO_FN_PTR(ReadMappedEntry_t, os::dll_lookup(handle, "ZIP_ReadMappedEntry"));
  GetNextEntry = CAST_TO_FN_PTR(GetNextEntry_t, os::dll_lookup(handle, "ZIP_GetNextEntry"));

  // ZIP_Close is not exported on Windows in JDK5.0 so don't abort if ZIP_Close is NULL
  if (ZipOpen == NULL || FindEntry == NULL || ReadEntry == NULL || GetNextEntry == NULL) {
    vm_exit_during_initialization("Corrupted ZIP library", path);
  }

  // Lookup canonicalize entry in libjava.dll
  void *javalib_handle = os::native_java_library();
  CanonicalizeEntry = CAST_TO_FN_PTR(canonicalize_fn_t, os::dll_lookup(javalib_handle, "Canonicalize"));
  // This lookup only works on 1.3. Do not check for non-null here
}

// PackageInfo data exists in order to support the java.lang.Package
// class.  A Package object provides information about a java package
// (version, vendor, etc.) which originates in the manifest of the jar
// file supplying the package.  For application classes, the ClassLoader
// object takes care of this.

// For system (boot) classes, the Java code in the Package class needs
// to be able to identify which source jar file contained the boot
// class, so that it can extract the manifest from it.  This table
// identifies java packages with jar files in the boot classpath.

// Because the boot classpath cannot change, the classpath index is
// sufficient to identify the source jar file or directory.  (Since
// directories have no manifests, the directory name is not required,
// but is available.)

// When using sharing -- the pathnames of entries in the boot classpath
// may not be the same at runtime as they were when the archive was
// created (NFS, Samba, etc.).  The actual files and directories named
// in the classpath must be the same files, in the same order, even
// though the exact name is not the same.

class PackageInfo: public BasicHashtableEntry<mtClass> {
public:
  const char* _pkgname;       // Package name
  int _classpath_index;       // Index of directory or JAR file loaded from

  PackageInfo* next() {
    return (PackageInfo*)BasicHashtableEntry<mtClass>::next();
  }

  const char* pkgname()           { return _pkgname; }
  void set_pkgname(char* pkgname) { _pkgname = pkgname; }

  const char* filename() {
    return ClassLoader::classpath_entry(_classpath_index)->name();
  }

  void set_index(int index) {
    _classpath_index = index;
  }
};


class PackageHashtable : public BasicHashtable<mtClass> {
private:
  inline unsigned int compute_hash(const char *s, int n) {
    unsigned int val = 0;
    while (--n >= 0) {
      val = *s++ + 31 * val;
    }
    return val;
  }

  PackageInfo* bucket(int index) {
    return (PackageInfo*)BasicHashtable<mtClass>::bucket(index);
  }

  PackageInfo* get_entry(int index, unsigned int hash,
                         const char* pkgname, size_t n) {
    for (PackageInfo* pp = bucket(index); pp != NULL; pp = pp->next()) {
      if (pp->hash() == hash &&
          strncmp(pkgname, pp->pkgname(), n) == 0 &&
          pp->pkgname()[n] == '\0') {
        return pp;
      }
    }
    return NULL;
  }

public:
  PackageHashtable(int table_size)
    : BasicHashtable<mtClass>(table_size, sizeof(PackageInfo)) {}

  PackageHashtable(int table_size, HashtableBucket<mtClass>* t, int number_of_entries)
    : BasicHashtable<mtClass>(table_size, sizeof(PackageInfo), t, number_of_entries) {}

  PackageInfo* get_entry(const char* pkgname, int n) {
    unsigned int hash = compute_hash(pkgname, n);
    return get_entry(hash_to_index(hash), hash, pkgname, n);
  }

  PackageInfo* new_entry(char* pkgname, int n) {
    unsigned int hash = compute_hash(pkgname, n);
    PackageInfo* pp;
    pp = (PackageInfo*)BasicHashtable<mtClass>::new_entry(hash);
    pp->set_pkgname(pkgname);
    return pp;
  }

  void add_entry(PackageInfo* pp) {
    int index = hash_to_index(pp->hash());
    BasicHashtable<mtClass>::add_entry(index, pp);
  }

  void copy_pkgnames(const char** packages) {
    int n = 0;
    for (int i = 0; i < table_size(); ++i) {
      for (PackageInfo* pp = bucket(i); pp != NULL; pp = pp->next()) {
        packages[n++] = pp->pkgname();
      }
    }
    assert(n == number_of_entries(), "just checking");
  }

  void copy_table(char** top, char* end, PackageHashtable* table);
};


void PackageHashtable::copy_table(char** top, char* end,
                                  PackageHashtable* table) {
  // Copy (relocate) the table to the shared space.
  BasicHashtable<mtClass>::copy_table(top, end);

  // Calculate the space needed for the package name strings.
  int i;
  int n = 0;
  for (i = 0; i < table_size(); ++i) {
    for (PackageInfo* pp = table->bucket(i);
                      pp != NULL;
                      pp = pp->next()) {
      n += (int)(strlen(pp->pkgname()) + 1);
    }
  }
  if (*top + n + sizeof(intptr_t) >= end) {
    report_out_of_shared_space(SharedMiscData);
  }

  // Copy the table data (the strings) to the shared space.
  n = align_size_up(n, sizeof(HeapWord));
  *(intptr_t*)(*top) = n;
  *top += sizeof(intptr_t);

  for (i = 0; i < table_size(); ++i) {
    for (PackageInfo* pp = table->bucket(i);
                      pp != NULL;
                      pp = pp->next()) {
      int n1 = (int)(strlen(pp->pkgname()) + 1);
      pp->set_pkgname((char*)memcpy(*top, pp->pkgname(), n1));
      *top += n1;
    }
  }
  *top = (char*)align_size_up((intptr_t)*top, sizeof(HeapWord));
}


void ClassLoader::copy_package_info_buckets(char** top, char* end) {
  _package_hash_table->copy_buckets(top, end);
}

void ClassLoader::copy_package_info_table(char** top, char* end) {
  _package_hash_table->copy_table(top, end, _package_hash_table);
}


PackageInfo* ClassLoader::lookup_package(const char *pkgname) {
  const char *cp = strrchr(pkgname, '/');
  if (cp != NULL) {
    // Package prefix found
    int n = cp - pkgname + 1;
    return _package_hash_table->get_entry(pkgname, n);
  }
  return NULL;
}


bool ClassLoader::add_package(const char *pkgname, int classpath_index, TRAPS) {
  assert(pkgname != NULL, "just checking");
  // Bootstrap loader no longer holds system loader lock obj serializing
  // load_instance_class and thereby add_package
  {
    MutexLocker ml(PackageTable_lock, THREAD);
    // First check for previously loaded entry
    PackageInfo* pp = lookup_package(pkgname);
    if (pp != NULL) {
      // Existing entry found, check source of package
      pp->set_index(classpath_index);
      return true;
    }

    const char *cp = strrchr(pkgname, '/');
    if (cp != NULL) {
      // Package prefix found
      int n = cp - pkgname + 1;

      char* new_pkgname = NEW_C_HEAP_ARRAY(char, n + 1, mtClass);
      if (new_pkgname == NULL) {
        return false;
      }

      memcpy(new_pkgname, pkgname, n);
      new_pkgname[n] = '\0';
      pp = _package_hash_table->new_entry(new_pkgname, n);
      pp->set_index(classpath_index);

      // Insert into hash table
      _package_hash_table->add_entry(pp);
    }
    return true;
  }
}


oop ClassLoader::get_system_package(const char* name, TRAPS) {
  PackageInfo* pp;
  {
    MutexLocker ml(PackageTable_lock, THREAD);
    pp = lookup_package(name);
  }
  if (pp == NULL) {
    return NULL;
  } else {
    Handle p = java_lang_String::create_from_str(pp->filename(), THREAD);
    return p();
  }
}


objArrayOop ClassLoader::get_system_packages(TRAPS) {
  ResourceMark rm(THREAD);
  int nof_entries;
  const char** packages;
  {
    MutexLocker ml(PackageTable_lock, THREAD);
    // Allocate resource char* array containing package names
    nof_entries = _package_hash_table->number_of_entries();
    if ((packages = NEW_RESOURCE_ARRAY(const char*, nof_entries)) == NULL) {
      return NULL;
    }
    _package_hash_table->copy_pkgnames(packages);
  }
  // Allocate objArray and fill with java.lang.String
  objArrayOop r = oopFactory::new_objArray(SystemDictionary::String_klass(),
                                           nof_entries, CHECK_0);
  objArrayHandle result(THREAD, r);
  for (int i = 0; i < nof_entries; i++) {
    Handle str = java_lang_String::create_from_str(packages[i], CHECK_0);
    result->obj_at_put(i, str());
  }

  return result();
}


instanceKlassHandle ClassLoader::load_classfile(Symbol* h_name, TRAPS) {
  ResourceMark rm(THREAD);
  EventMark m("loading class %s", h_name->as_C_string());
  ThreadProfilerMark tpm(ThreadProfilerMark::classLoaderRegion);

  stringStream st;
  // st.print() uses too much stack space while handling a StackOverflowError
  // st.print("%s.class", h_name->as_utf8());
  st.print_raw(h_name->as_utf8());
  st.print_raw(".class");
  char* name = st.as_string();

  // Lookup stream for parsing .class file
  ClassFileStream* stream = NULL;
  int classpath_index = 0;
  {
    PerfClassTraceTime vmtimer(perf_sys_class_lookup_time(),
                               ((JavaThread*) THREAD)->get_thread_stat()->perf_timers_addr(),
                               PerfClassTraceTime::CLASS_LOAD);
    ClassPathEntry* e = _first_entry;
    while (e != NULL) {
      stream = e->open_stream(name, CHECK_NULL);
      if (stream != NULL) {
        break;
      }
      e = e->next();
      ++classpath_index;
    }
  }

  instanceKlassHandle h;
  if (stream != NULL) {

    // class file found, parse it
    ClassFileParser parser(stream);
    ClassLoaderData* loader_data = ClassLoaderData::the_null_class_loader_data();
    Handle protection_domain;
    TempNewSymbol parsed_name = NULL;
    instanceKlassHandle result = parser.parseClassFile(h_name,
                                                       loader_data,
                                                       protection_domain,
                                                       parsed_name,
                                                       false,
                                                       CHECK_(h));

    // add to package table
    if (add_package(name, classpath_index, THREAD)) {
      h = result;
    }
  }

  return h;
}


void ClassLoader::create_package_info_table(HashtableBucket<mtClass> *t, int length,
                                            int number_of_entries) {
  assert(_package_hash_table == NULL, "One package info table allowed.");
  assert(length == package_hash_table_size * sizeof(HashtableBucket<mtClass>),
         "bad shared package info size.");
  _package_hash_table = new PackageHashtable(package_hash_table_size, t,
                                             number_of_entries);
}


void ClassLoader::create_package_info_table() {
    assert(_package_hash_table == NULL, "shouldn't have one yet");
    _package_hash_table = new PackageHashtable(package_hash_table_size);
}


// 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() {
  assert(_package_hash_table == NULL, "should have been initialized by now.");
  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.
    // Also two additional counters are created to see whether 'UnsyncloadClass'
    // flag is being set or not and how many times load_instance_class call
    // fails with linkageError etc.
    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");

    NEWPERFEVENTCOUNTER(_isUnsyncloadClass, SUN_CLS, "isUnsyncloadClassSet");
    NEWPERFEVENTCOUNTER(_load_instance_class_failCounter, SUN_CLS,
                        "loadInstanceClassFailRate");

    // increment the isUnsyncloadClass counter if UnsyncloadClass is set.
    if (UnsyncloadClass) {
      _isUnsyncloadClass->inc();
    }
  }

  // lookup zip library entry points
  load_zip_library();
  // initialize search path
  setup_bootstrap_search_path();
  if (LazyBootClassLoader) {
    // set up meta index which makes boot classpath initialization lazier
    setup_meta_index();
  }
}


jlong ClassLoader::classloader_time_ms() {
  return UsePerfData ?
    Management::ticks_to_ms(_perf_accumulated_time->get_value()) : -1;
}

jlong ClassLoader::class_init_count() {
  return UsePerfData ? _perf_classes_inited->get_value() : -1;
}

jlong ClassLoader::class_init_time_ms() {
  return UsePerfData ?
    Management::ticks_to_ms(_perf_class_init_time->get_value()) : -1;
}

jlong ClassLoader::class_verify_time_ms() {
  return UsePerfData ?
    Management::ticks_to_ms(_perf_class_verify_time->get_value()) : -1;
}

jlong ClassLoader::class_link_count() {
  return UsePerfData ? _perf_classes_linked->get_value() : -1;
}

jlong ClassLoader::class_link_time_ms() {
  return UsePerfData ?
    Management::ticks_to_ms(_perf_class_link_time->get_value()) : -1;
}

int ClassLoader::compute_Object_vtable() {
  // hardwired for JDK1.2 -- would need to duplicate class file parsing
  // code to determine actual value from file
  // Would be value '11' if finals were in vtable
  int JDK_1_2_Object_vtable_size = 5;
  return JDK_1_2_Object_vtable_size * vtableEntry::size();
}


void classLoader_init() {
  ClassLoader::initialize();
}


bool ClassLoader::get_canonical_path(char* orig, char* out, int len) {
  assert(orig != NULL && out != NULL && len > 0, "bad arguments");
  if (CanonicalizeEntry != NULL) {
    JNIEnv* env = JavaThread::current()->jni_environment();
    if ((CanonicalizeEntry)(env, os::native_path(orig), out, len) < 0) {
      return false;
    }
  } else {
    // On JDK 1.2.2 the Canonicalize does not exist, so just do nothing
    strncpy(out, orig, len);
    out[len - 1] = '\0';
  }
  return true;
}

#ifndef PRODUCT

void ClassLoader::verify() {
  _package_hash_table->verify();
}


// CompileTheWorld
//
// Iterates over all class path entries and forces compilation of all methods
// in all classes found. Currently, only zip/jar archives are searched.
//
// The classes are loaded by the Java level bootstrap class loader, and the
// initializer is called. If DelayCompilationDuringStartup is true (default),
// the interpreter will run the initialization code. Note that forcing
// initialization in this way could potentially lead to initialization order
// problems, in which case we could just force the initialization bit to be set.


// We need to iterate over the contents of a zip/jar file, so we replicate the
// jzcell and jzfile definitions from zip_util.h but rename jzfile to real_jzfile,
// since jzfile already has a void* definition.
//
// Note that this is only used in debug mode.
//
// HotSpot integration note:
// Matches zip_util.h 1.14 99/06/01 from jdk1.3 beta H build


// JDK 1.3 version
typedef struct real_jzentry13 {         /* Zip file entry */
    char *name;                 /* entry name */
    jint time;                  /* modification time */
    jint size;                  /* size of uncompressed data */
    jint csize;                 /* size of compressed data (zero if uncompressed) */
    jint crc;                   /* crc of uncompressed data */
    char *comment;              /* optional zip file comment */
    jbyte *extra;               /* optional extra data */
    jint pos;                   /* position of LOC header (if negative) or data */
} real_jzentry13;

typedef struct real_jzfile13 {  /* Zip file */
    char *name;                 /* zip file name */
    jint refs;                  /* number of active references */
    jint fd;                    /* open file descriptor */
    void *lock;                 /* read lock */
    char *comment;              /* zip file comment */
    char *msg;                  /* zip error message */
    void *entries;              /* array of hash cells */
    jint total;                 /* total number of entries */
    unsigned short *table;      /* Hash chain heads: indexes into entries */
    jint tablelen;              /* number of hash eads */
    real_jzfile13 *next;        /* next zip file in search list */
    jzentry *cache;             /* we cache the most recently freed jzentry */
    /* Information on metadata names in META-INF directory */
    char **metanames;           /* array of meta names (may have null names) */
    jint metacount;             /* number of slots in metanames array */
    /* If there are any per-entry comments, they are in the comments array */
    char **comments;
} real_jzfile13;

// JDK 1.2 version
typedef struct real_jzentry12 {  /* Zip file entry */
    char *name;                  /* entry name */
    jint time;                   /* modification time */
    jint size;                   /* size of uncompressed data */
    jint csize;                  /* size of compressed data (zero if uncompressed) */
    jint crc;                    /* crc of uncompressed data */
    char *comment;               /* optional zip file comment */
    jbyte *extra;                /* optional extra data */
    jint pos;                    /* position of LOC header (if negative) or data */
    struct real_jzentry12 *next; /* next entry in hash table */
} real_jzentry12;

typedef struct real_jzfile12 {  /* Zip file */
    char *name;                 /* zip file name */
    jint refs;                  /* number of active references */
    jint fd;                    /* open file descriptor */
    void *lock;                 /* read lock */
    char *comment;              /* zip file comment */
    char *msg;                  /* zip error message */
    real_jzentry12 *entries;    /* array of zip entries */
    jint total;                 /* total number of entries */
    real_jzentry12 **table;     /* hash table of entries */
    jint tablelen;              /* number of buckets */
    jzfile *next;               /* next zip file in search list */
} real_jzfile12;


void ClassPathDirEntry::compile_the_world(Handle loader, TRAPS) {
  // For now we only compile all methods in all classes in zip/jar files
  tty->print_cr("CompileTheWorld : Skipped classes in %s", _dir);
  tty->cr();
}


bool ClassPathDirEntry::is_rt_jar() {
  return false;
}

void ClassPathZipEntry::compile_the_world(Handle loader, TRAPS) {
  if (JDK_Version::is_jdk12x_version()) {
    compile_the_world12(loader, THREAD);
  } else {
    compile_the_world13(loader, THREAD);
  }
  if (HAS_PENDING_EXCEPTION) {
    if (PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
      CLEAR_PENDING_EXCEPTION;
      tty->print_cr("\nCompileTheWorld : Ran out of memory\n");
      tty->print_cr("Increase class metadata storage if a limit was set");
    } else {
      tty->print_cr("\nCompileTheWorld : Unexpected exception occurred\n");
    }
  }
}

// Version that works for JDK 1.3.x
void ClassPathZipEntry::compile_the_world13(Handle loader, TRAPS) {
  real_jzfile13* zip = (real_jzfile13*) _zip;
  tty->print_cr("CompileTheWorld : Compiling all classes in %s", zip->name);
  tty->cr();
  // Iterate over all entries in zip file
  for (int n = 0; ; n++) {
    real_jzentry13 * ze = (real_jzentry13 *)((*GetNextEntry)(_zip, n));
    if (ze == NULL) break;
    ClassLoader::compile_the_world_in(ze->name, loader, CHECK);
  }
}


// Version that works for JDK 1.2.x
void ClassPathZipEntry::compile_the_world12(Handle loader, TRAPS) {
  real_jzfile12* zip = (real_jzfile12*) _zip;
  tty->print_cr("CompileTheWorld : Compiling all classes in %s", zip->name);
  tty->cr();
  // Iterate over all entries in zip file
  for (int n = 0; ; n++) {
    real_jzentry12 * ze = (real_jzentry12 *)((*GetNextEntry)(_zip, n));
    if (ze == NULL) break;
    ClassLoader::compile_the_world_in(ze->name, loader, CHECK);
  }
}

bool ClassPathZipEntry::is_rt_jar() {
  if (JDK_Version::is_jdk12x_version()) {
    return is_rt_jar12();
  } else {
    return is_rt_jar13();
  }
}

// JDK 1.3 version
bool ClassPathZipEntry::is_rt_jar13() {
  real_jzfile13* zip = (real_jzfile13*) _zip;
  int len = (int)strlen(zip->name);
  // Check whether zip name ends in "rt.jar"
  // This will match other archives named rt.jar as well, but this is
  // only used for debugging.
  return (len >= 6) && (strcasecmp(zip->name + len - 6, "rt.jar") == 0);
}

// JDK 1.2 version
bool ClassPathZipEntry::is_rt_jar12() {
  real_jzfile12* zip = (real_jzfile12*) _zip;
  int len = (int)strlen(zip->name);
  // Check whether zip name ends in "rt.jar"
  // This will match other archives named rt.jar as well, but this is
  // only used for debugging.
  return (len >= 6) && (strcasecmp(zip->name + len - 6, "rt.jar") == 0);
}

void LazyClassPathEntry::compile_the_world(Handle loader, TRAPS) {
  ClassPathEntry* cpe = resolve_entry(THREAD);
  if (cpe != NULL) {
    cpe->compile_the_world(loader, CHECK);
  }
}

bool LazyClassPathEntry::is_rt_jar() {
  Thread* THREAD = Thread::current();
  ClassPathEntry* cpe = resolve_entry(THREAD);
  return (cpe != NULL) ? cpe->is_jar_file() : false;
}

void ClassLoader::compile_the_world() {
  EXCEPTION_MARK;
  HandleMark hm(THREAD);
  ResourceMark rm(THREAD);
  // Make sure we don't run with background compilation
  BackgroundCompilation = false;
  // Find bootstrap loader
  Handle system_class_loader (THREAD, SystemDictionary::java_system_loader());
  // Iterate over all bootstrap class path entries
  ClassPathEntry* e = _first_entry;
  jlong start = os::javaTimeMillis();
  while (e != NULL) {
    // We stop at rt.jar, unless it is the first bootstrap path entry
    if (e->is_rt_jar() && e != _first_entry) break;
    e->compile_the_world(system_class_loader, CATCH);
    e = e->next();
  }
  jlong end = os::javaTimeMillis();
  tty->print_cr("CompileTheWorld : Done (%d classes, %d methods, %d ms)",
                _compile_the_world_class_counter, _compile_the_world_method_counter, (end - start));
  {
    // Print statistics as if before normal exit:
    extern void print_statistics();
    print_statistics();
  }
  vm_exit(0);
}

int ClassLoader::_compile_the_world_class_counter = 0;
int ClassLoader::_compile_the_world_method_counter = 0;
static int _codecache_sweep_counter = 0;

// Filter out all exceptions except OOMs
static void clear_pending_exception_if_not_oom(TRAPS) {
  if (HAS_PENDING_EXCEPTION &&
      !PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())) {
    CLEAR_PENDING_EXCEPTION;
  }
  // The CHECK at the caller will propagate the exception out
}

/**
 * Returns if the given method should be compiled when doing compile-the-world.
 *
 * TODO:  This should be a private method in a CompileTheWorld class.
 */
static bool can_be_compiled(methodHandle m, int comp_level) {
  assert(CompileTheWorld, "must be");

  // It's not valid to compile a native wrapper for MethodHandle methods
  // that take a MemberName appendix since the bytecode signature is not
  // correct.
  vmIntrinsics::ID iid = m->intrinsic_id();
  if (MethodHandles::is_signature_polymorphic(iid) && MethodHandles::has_member_arg(iid)) {
    return false;
  }

  return CompilationPolicy::can_be_compiled(m, comp_level);
}

void ClassLoader::compile_the_world_in(char* name, Handle loader, TRAPS) {
  int len = (int)strlen(name);
  if (len > 6 && strcmp(".class", name + len - 6) == 0) {
    // We have a .class file
    char buffer[2048];
    strncpy(buffer, name, len - 6);
    buffer[len-6] = 0;
    // If the file has a period after removing .class, it's not really a
    // valid class file.  The class loader will check everything else.
    if (strchr(buffer, '.') == NULL) {
      _compile_the_world_class_counter++;
      if (_compile_the_world_class_counter > CompileTheWorldStopAt) return;

      // Construct name without extension
      TempNewSymbol sym = SymbolTable::new_symbol(buffer, CHECK);
      // Use loader to load and initialize class
      Klass* ik = SystemDictionary::resolve_or_null(sym, loader, Handle(), THREAD);
      instanceKlassHandle k (THREAD, ik);
      if (k.not_null() && !HAS_PENDING_EXCEPTION) {
        k->initialize(THREAD);
      }
      bool exception_occurred = HAS_PENDING_EXCEPTION;
      clear_pending_exception_if_not_oom(CHECK);
      if (CompileTheWorldPreloadClasses && k.not_null()) {
        ConstantPool::preload_and_initialize_all_classes(k->constants(), THREAD);
        if (HAS_PENDING_EXCEPTION) {
          // If something went wrong in preloading we just ignore it
          clear_pending_exception_if_not_oom(CHECK);
          tty->print_cr("Preloading failed for (%d) %s", _compile_the_world_class_counter, buffer);
        }
      }

      if (_compile_the_world_class_counter >= CompileTheWorldStartAt) {
        if (k.is_null() || exception_occurred) {
          // If something went wrong (e.g. ExceptionInInitializerError) we skip this class
          tty->print_cr("CompileTheWorld (%d) : Skipping %s", _compile_the_world_class_counter, buffer);
        } else {
          tty->print_cr("CompileTheWorld (%d) : %s", _compile_the_world_class_counter, buffer);
          // Preload all classes to get around uncommon traps
          // Iterate over all methods in class
          int comp_level = CompilationPolicy::policy()->initial_compile_level();
          for (int n = 0; n < k->methods()->length(); n++) {
            methodHandle m (THREAD, k->methods()->at(n));
            if (can_be_compiled(m, comp_level)) {
              if (++_codecache_sweep_counter == CompileTheWorldSafepointInterval) {
                // Give sweeper a chance to keep up with CTW
                VM_ForceSafepoint op;
                VMThread::execute(&op);
                _codecache_sweep_counter = 0;
              }
              // Force compilation
              CompileBroker::compile_method(m, InvocationEntryBci, comp_level,
                                            methodHandle(), 0, "CTW", THREAD);
              if (HAS_PENDING_EXCEPTION) {
                clear_pending_exception_if_not_oom(CHECK);
                tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
              } else {
                _compile_the_world_method_counter++;
              }
              if (TieredCompilation && TieredStopAtLevel >= CompLevel_full_optimization) {
                // Clobber the first compile and force second tier compilation
                nmethod* nm = m->code();
                if (nm != NULL) {
                  // Throw out the code so that the code cache doesn't fill up
                  nm->make_not_entrant();
                  m->clear_code();
                }
                CompileBroker::compile_method(m, InvocationEntryBci, CompLevel_full_optimization,
                                              methodHandle(), 0, "CTW", THREAD);
                if (HAS_PENDING_EXCEPTION) {
                  clear_pending_exception_if_not_oom(CHECK);
                  tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
                } else {
                  _compile_the_world_method_counter++;
                }
              }
            } else {
              tty->print_cr("CompileTheWorld (%d) : Skipping method: %s", _compile_the_world_class_counter, m->name_and_sig_as_C_string());
            }

            nmethod* nm = m->code();
            if (nm != NULL) {
              // Throw out the code so that the code cache doesn't fill up
              nm->make_not_entrant();
              m->clear_code();
            }
          }
        }
      }
    }
  }
}

#endif //PRODUCT

// Please keep following two functions at end of this file. With them placed at top or in middle of the file,
// they could get inlined by agressive compiler, an unknown trick, see bug 6966589.
void PerfClassTraceTime::initialize() {
  if (!UsePerfData) return;

  if (_eventp != NULL) {
    // increment the event counter
    _eventp->inc();
  }

  // stop the current active thread-local timer to measure inclusive time
  _prev_active_event = -1;
  for (int i=0; i < EVENT_TYPE_COUNT; i++) {
     if (_timers[i].is_active()) {
       assert(_prev_active_event == -1, "should have only one active timer");
       _prev_active_event = i;
       _timers[i].stop();
     }
  }

  if (_recursion_counters == NULL || (_recursion_counters[_event_type])++ == 0) {
    // start the inclusive timer if not recursively called
    _t.start();
  }

  // start thread-local timer of the given event type
   if (!_timers[_event_type].is_active()) {
    _timers[_event_type].start();
  }
}

PerfClassTraceTime::~PerfClassTraceTime() {
  if (!UsePerfData) return;

  // stop the thread-local timer as the event completes
  // and resume the thread-local timer of the event next on the stack
  _timers[_event_type].stop();
  jlong selftime = _timers[_event_type].ticks();

  if (_prev_active_event >= 0) {
    _timers[_prev_active_event].start();
  }

  if (_recursion_counters != NULL && --(_recursion_counters[_event_type]) > 0) return;

  // increment the counters only on the leaf call
  _t.stop();
  _timep->inc(_t.ticks());
  if (_selftimep != NULL) {
    _selftimep->inc(selftime);
  }
  // add all class loading related event selftime to the accumulated time counter
  ClassLoader::perf_accumulated_time()->inc(selftime);

  // reset the timer
  _timers[_event_type].reset();
}

Other Java examples (source code examples)

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