Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.com if you need additional information or

  * have any questions.

  *

  */

 // Interface for manipulating the basic Java classes.

 //

 // All dependencies on layout of actual Java classes should be kept here.

 // If the layout of any of the classes above changes the offsets must be adjusted.

 //

 // For most classes we hardwire the offsets for performance reasons. In certain

 // cases (e.g. java.security.AccessControlContext) we compute the offsets at

 // startup since the layout here differs between JDK1.2 and JDK1.3.

 //

 // Note that fields (static and non-static) are arranged with oops before non-oops

 // on a per class basis. The offsets below have to reflect this ordering.

 //

 // When editing the layouts please update the check_offset verification code

 // correspondingly. The names in the enums must be identical to the actual field

 // names in order for the verification code to work.

 // Interface to java.lang.String objects

 class java_lang_String : AllStatic {

  private:

   enum {

     hc_value_offset  = 0,

     hc_offset_offset = 1

     //hc_count_offset = 2  -- not a word-scaled offset

     //hc_hash_offset  = 3  -- not a word-scaled offset

   };

   static int value_offset;

   static int offset_offset;

   static int count_offset;

   static int hash_offset;

   static Handle basic_create(int length, bool tenured, TRAPS);

   static Handle basic_create_from_unicode(jchar* unicode, int length, bool tenured, TRAPS);

   static void set_value( oop string, typeArrayOop buffer) { string->obj_field_put(value_offset,  (oop)buffer); }

   static void set_offset(oop string, int offset)          { string->int_field_put(offset_offset, offset); }

   static void set_count( oop string, int count)           { string->int_field_put(count_offset,  count);  }

  public:

   // Instance creation

   static Handle create_from_unicode(jchar* unicode, int len, TRAPS);

   static Handle create_tenured_from_unicode(jchar* unicode, int len, TRAPS);

   static oop    create_oop_from_unicode(jchar* unicode, int len, TRAPS);

   static Handle create_from_str(const char* utf8_str, TRAPS);

   static oop    create_oop_from_str(const char* utf8_str, TRAPS);

   static Handle create_from_symbol(symbolHandle symbol, TRAPS);

   static Handle create_from_platform_dependent_str(const char* str, TRAPS);

   static Handle char_converter(Handle java_string, jchar from_char, jchar to_char, TRAPS);

   static int value_offset_in_bytes()  { return value_offset;  }

   static int count_offset_in_bytes()  { return count_offset;  }

   static int offset_offset_in_bytes() { return offset_offset; }

   static int hash_offset_in_bytes()   { return hash_offset;   }

   // Accessors

   static typeArrayOop value(oop java_string) {

     assert(is_instance(java_string), "must be java_string");

     return (typeArrayOop) java_string->obj_field(value_offset);

   }

   static int offset(oop java_string) {

     assert(is_instance(java_string), "must be java_string");

     return java_string->int_field(offset_offset);

   }

   static int length(oop java_string) {

     assert(is_instance(java_string), "must be java_string");

     return java_string->int_field(count_offset);

   }

   static int utf8_length(oop java_string);

   // String converters

   static char*  as_utf8_string(oop java_string);

   static char*  as_utf8_string(oop java_string, int start, int len);

   static char*  as_platform_dependent_str(Handle java_string, TRAPS);

   static jchar* as_unicode_string(oop java_string, int& length);

   static bool equals(oop java_string, jchar* chars, int len);

   // Conversion between '.' and '/' formats

   static Handle externalize_classname(Handle java_string, TRAPS) { return char_converter(java_string, '/', '.', THREAD); }

   static Handle internalize_classname(Handle java_string, TRAPS) { return char_converter(java_string, '.', '/', THREAD); }

   // Conversion

   static symbolHandle as_symbol(Handle java_string, TRAPS);

   static symbolOop as_symbol_or_null(oop java_string);

   // Testers

   static bool is_instance(oop obj) {

     return obj != NULL && obj->klass() == SystemDictionary::string_klass();

   }

   // Debugging

   static void print(Handle java_string, outputStream* st);

   friend class JavaClasses;

 };

 // Interface to java.lang.Class objects

 class java_lang_Class : AllStatic {

    friend class VMStructs;

  private:

   // The fake offsets are added by the class loader when java.lang.Class is loaded

   enum {

     hc_klass_offset                = 0,

     hc_array_klass_offset          = 1,

     hc_resolved_constructor_offset = 2,

     hc_number_of_fake_oop_fields   = 3

   };

   static int klass_offset;

   static int resolved_constructor_offset;

   static int array_klass_offset;

   static int number_of_fake_oop_fields;

   static void compute_offsets();

   static bool offsets_computed;

   static int classRedefinedCount_offset;

   static int parallelCapable_offset;

  public:

   // Instance creation

   static oop  create_mirror(KlassHandle k, TRAPS);

   static oop  create_basic_type_mirror(const char* basic_type_name, BasicType type, TRAPS);

   // Conversion

   static klassOop as_klassOop(oop java_class);

   static BasicType as_BasicType(oop java_class, klassOop* reference_klass = NULL);

   static symbolOop as_signature(oop java_class, bool intern_if_not_found, TRAPS);

   static void print_signature(oop java_class, outputStream *st);

   // Testing

   static bool is_instance(oop obj) {

     return obj != NULL && obj->klass() == SystemDictionary::class_klass();

   }

   static bool is_primitive(oop java_class);

   static BasicType primitive_type(oop java_class);

   static oop primitive_mirror(BasicType t);

   // JVM_NewInstance support

   static methodOop resolved_constructor(oop java_class);

   static void set_resolved_constructor(oop java_class, methodOop constructor);

   // JVM_NewArray support

   static klassOop array_klass(oop java_class);

   static void set_array_klass(oop java_class, klassOop klass);

   // compiler support for class operations

   static int klass_offset_in_bytes() { return klass_offset; }

   static int resolved_constructor_offset_in_bytes() { return resolved_constructor_offset; }

   static int array_klass_offset_in_bytes() { return array_klass_offset; }

   // Support for classRedefinedCount field

   static int classRedefinedCount(oop the_class_mirror);

   static void set_classRedefinedCount(oop the_class_mirror, int value);

   // Support for parallelCapable field

   static bool parallelCapable(oop the_class_mirror);

   // Debugging

   friend class JavaClasses;

   friend class instanceKlass;   // verification code accesses offsets

   friend class ClassFileParser; // access to number_of_fake_fields

 };

 // Interface to java.lang.Thread objects

 class java_lang_Thread : AllStatic {

  private:

   // Note that for this class the layout changed between JDK1.2 and JDK1.3,

   // so we compute the offsets at startup rather than hard-wiring them.

   static int _name_offset;

   static int _group_offset;

   static int _contextClassLoader_offset;

   static int _inheritedAccessControlContext_offset;

   static int _priority_offset;

   static int _eetop_offset;

   static int _daemon_offset;

   static int _stillborn_offset;

   static int _stackSize_offset;

   static int _tid_offset;

   static int _thread_status_offset;

   static int _park_blocker_offset;

   static int _park_event_offset ;

   static void compute_offsets();

  public:

   // Instance creation

   static oop create();

   // Returns the JavaThread associated with the thread obj

   static JavaThread* thread(oop java_thread);

   // Set JavaThread for instance

   static void set_thread(oop java_thread, JavaThread* thread);

   // Name

   static typeArrayOop name(oop java_thread);

   static void set_name(oop java_thread, typeArrayOop name);

   // Priority

   static ThreadPriority priority(oop java_thread);

   static void set_priority(oop java_thread, ThreadPriority priority);

   // Thread group

   static oop  threadGroup(oop java_thread);

   // Stillborn

   static bool is_stillborn(oop java_thread);

   static void set_stillborn(oop java_thread);

   // Alive (NOTE: this is not really a field, but provides the correct

   // definition without doing a Java call)

   static bool is_alive(oop java_thread);

   // Daemon

   static bool is_daemon(oop java_thread);

   static void set_daemon(oop java_thread);

   // Context ClassLoader

   static oop context_class_loader(oop java_thread);

   // Control context

   static oop inherited_access_control_context(oop java_thread);

   // Stack size hint

   static jlong stackSize(oop java_thread);

   // Thread ID

   static jlong thread_id(oop java_thread);

   // Blocker object responsible for thread parking

   static oop park_blocker(oop java_thread);

   // Pointer to type-stable park handler, encoded as jlong.

   // Should be set when apparently null

   // For details, see unsafe.cpp Unsafe_Unpark

   static jlong park_event(oop java_thread);

   static bool set_park_event(oop java_thread, jlong ptr);

   // Java Thread Status for JVMTI and M&M use.

   // This thread status info is saved in threadStatus field of

   // java.lang.Thread java class.

   enum ThreadStatus {

     NEW                      = 0,

     RUNNABLE                 = JVMTI_THREAD_STATE_ALIVE +          // runnable / running

                                JVMTI_THREAD_STATE_RUNNABLE,

     SLEEPING                 = JVMTI_THREAD_STATE_ALIVE +          // Thread.sleep()

                                JVMTI_THREAD_STATE_WAITING +

                                JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT +

                                JVMTI_THREAD_STATE_SLEEPING,

     IN_OBJECT_WAIT           = JVMTI_THREAD_STATE_ALIVE +          // Object.wait()

                                JVMTI_THREAD_STATE_WAITING +

                                JVMTI_THREAD_STATE_WAITING_INDEFINITELY +

                                JVMTI_THREAD_STATE_IN_OBJECT_WAIT,

     IN_OBJECT_WAIT_TIMED     = JVMTI_THREAD_STATE_ALIVE +          // Object.wait(long)

                                JVMTI_THREAD_STATE_WAITING +

                                JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT +

                                JVMTI_THREAD_STATE_IN_OBJECT_WAIT,

     PARKED                   = JVMTI_THREAD_STATE_ALIVE +          // LockSupport.park()

                                JVMTI_THREAD_STATE_WAITING +

                                JVMTI_THREAD_STATE_WAITING_INDEFINITELY +

                                JVMTI_THREAD_STATE_PARKED,

     PARKED_TIMED             = JVMTI_THREAD_STATE_ALIVE +          // LockSupport.park(long)

                                JVMTI_THREAD_STATE_WAITING +

                                JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT +

                                JVMTI_THREAD_STATE_PARKED,

     BLOCKED_ON_MONITOR_ENTER = JVMTI_THREAD_STATE_ALIVE +          // (re-)entering a synchronization block

                                JVMTI_THREAD_STATE_BLOCKED_ON_MONITOR_ENTER,

     TERMINATED               = JVMTI_THREAD_STATE_TERMINATED

   };

   // Write thread status info to threadStatus field of java.lang.Thread.

   static void set_thread_status(oop java_thread_oop, ThreadStatus status);

   // Read thread status info from threadStatus field of java.lang.Thread.

   static ThreadStatus get_thread_status(oop java_thread_oop);

   static const char*  thread_status_name(oop java_thread_oop);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.ThreadGroup objects

 class java_lang_ThreadGroup : AllStatic {

  private:

   static int _parent_offset;

   static int _name_offset;

   static int _threads_offset;

   static int _groups_offset;

   static int _maxPriority_offset;

   static int _destroyed_offset;

   static int _daemon_offset;

   static int _vmAllowSuspension_offset;

   static int _nthreads_offset;

   static int _ngroups_offset;

   static void compute_offsets();

  public:

   // parent ThreadGroup

   static oop  parent(oop java_thread_group);

   // name

   static typeArrayOop name(oop java_thread_group);

   // ("name as oop" accessor is not necessary)

   // Number of threads in group

   static int nthreads(oop java_thread_group);

   // threads

   static objArrayOop threads(oop java_thread_group);

   // Number of threads in group

   static int ngroups(oop java_thread_group);

   // groups

   static objArrayOop groups(oop java_thread_group);

   // maxPriority in group

   static ThreadPriority maxPriority(oop java_thread_group);

   // Destroyed

   static bool is_destroyed(oop java_thread_group);

   // Daemon

   static bool is_daemon(oop java_thread_group);

   // vmAllowSuspension

   static bool is_vmAllowSuspension(oop java_thread_group);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.Throwable objects

 class java_lang_Throwable: AllStatic {

   friend class BacktraceBuilder;

  private:

   // Offsets

   enum {

     hc_backtrace_offset     =  0,

     hc_detailMessage_offset =  1,

     hc_cause_offset         =  2,  // New since 1.4

     hc_stackTrace_offset    =  3   // New since 1.4

   };

   // Trace constants

   enum {

     trace_methods_offset = 0,

     trace_bcis_offset    = 1,

     trace_next_offset    = 2,

     trace_size           = 3,

     trace_chunk_size     = 32

   };

   static int backtrace_offset;

   static int detailMessage_offset;

   static int cause_offset;

   static int stackTrace_offset;

   // Printing

   static char* print_stack_element_to_buffer(methodOop method, int bci);

   static void print_to_stream(Handle stream, const char* str);

   // StackTrace (programmatic access, new since 1.4)

   static void clear_stacktrace(oop throwable);

   // No stack trace available

   static const char* no_stack_trace_message();

  public:

   // Backtrace

   static oop backtrace(oop throwable);

   static void set_backtrace(oop throwable, oop value);

   // Needed by JVMTI to filter out this internal field.

   static int get_backtrace_offset() { return backtrace_offset;}

   static int get_detailMessage_offset() { return detailMessage_offset;}

   // Message

   static oop message(oop throwable);

   static oop message(Handle throwable);

   static void set_message(oop throwable, oop value);

   // Print stack trace stored in exception by call-back to Java

   // Note: this is no longer used in Merlin, but we still suppport

   // it for compatibility.

   static void print_stack_trace(oop throwable, oop print_stream);

   static void print_stack_element(Handle stream, methodOop method, int bci);

   static void print_stack_element(outputStream *st, methodOop method, int bci);

   static void print_stack_usage(Handle stream);

   // Allocate space for backtrace (created but stack trace not filled in)

   static void allocate_backtrace(Handle throwable, TRAPS);

   // Fill in current stack trace for throwable with preallocated backtrace (no GC)

   static void fill_in_stack_trace_of_preallocated_backtrace(Handle throwable);

   // Fill in current stack trace, can cause GC

   static void fill_in_stack_trace(Handle throwable, TRAPS);

   static void fill_in_stack_trace(Handle throwable);

   // Programmatic access to stack trace

   static oop  get_stack_trace_element(oop throwable, int index, TRAPS);

   static int  get_stack_trace_depth(oop throwable, TRAPS);

   // Printing

   static void print(oop throwable, outputStream* st);

   static void print(Handle throwable, outputStream* st);

   static void print_stack_trace(oop throwable, outputStream* st);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.reflect.AccessibleObject objects

 class java_lang_reflect_AccessibleObject: AllStatic {

  private:

   // Note that to reduce dependencies on the JDK we compute these

   // offsets at run-time.

   static int override_offset;

   static void compute_offsets();

  public:

   // Accessors

   static jboolean override(oop reflect);

   static void set_override(oop reflect, jboolean value);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.reflect.Method objects

 class java_lang_reflect_Method : public java_lang_reflect_AccessibleObject {

  private:

   // Note that to reduce dependencies on the JDK we compute these

   // offsets at run-time.

   static int clazz_offset;

   static int name_offset;

   static int returnType_offset;

   static int parameterTypes_offset;

   static int exceptionTypes_offset;

   static int slot_offset;

   static int modifiers_offset;

   static int signature_offset;

   static int annotations_offset;

   static int parameter_annotations_offset;

   static int annotation_default_offset;

   static void compute_offsets();

  public:

   // Allocation

   static Handle create(TRAPS);

   // Accessors

   static oop clazz(oop reflect);

   static void set_clazz(oop reflect, oop value);

   static oop name(oop method);

   static void set_name(oop method, oop value);

   static oop return_type(oop method);

   static void set_return_type(oop method, oop value);

   static oop parameter_types(oop method);

   static void set_parameter_types(oop method, oop value);

   static oop exception_types(oop method);

   static void set_exception_types(oop method, oop value);

   static int slot(oop reflect);

   static void set_slot(oop reflect, int value);

   static int modifiers(oop method);

   static void set_modifiers(oop method, int value);

   static bool has_signature_field();

   static oop signature(oop method);

   static void set_signature(oop method, oop value);

   static bool has_annotations_field();

   static oop annotations(oop method);

   static void set_annotations(oop method, oop value);

   static bool has_parameter_annotations_field();

   static oop parameter_annotations(oop method);

   static void set_parameter_annotations(oop method, oop value);

   static bool has_annotation_default_field();

   static oop annotation_default(oop method);

   static void set_annotation_default(oop method, oop value);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.reflect.Constructor objects

 class java_lang_reflect_Constructor : public java_lang_reflect_AccessibleObject {

  private:

   // Note that to reduce dependencies on the JDK we compute these

   // offsets at run-time.

   static int clazz_offset;

   static int parameterTypes_offset;

   static int exceptionTypes_offset;

   static int slot_offset;

   static int modifiers_offset;

   static int signature_offset;

   static int annotations_offset;

   static int parameter_annotations_offset;

   static void compute_offsets();

  public:

   // Allocation

   static Handle create(TRAPS);

   // Accessors

   static oop clazz(oop reflect);

   static void set_clazz(oop reflect, oop value);

   static oop parameter_types(oop constructor);

   static void set_parameter_types(oop constructor, oop value);

   static oop exception_types(oop constructor);

   static void set_exception_types(oop constructor, oop value);

   static int slot(oop reflect);

   static void set_slot(oop reflect, int value);

   static int modifiers(oop constructor);

   static void set_modifiers(oop constructor, int value);

   static bool has_signature_field();

   static oop signature(oop constructor);

   static void set_signature(oop constructor, oop value);

   static bool has_annotations_field();

   static oop annotations(oop constructor);

   static void set_annotations(oop constructor, oop value);

   static bool has_parameter_annotations_field();

   static oop parameter_annotations(oop method);

   static void set_parameter_annotations(oop method, oop value);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.reflect.Field objects

 class java_lang_reflect_Field : public java_lang_reflect_AccessibleObject {

  private:

   // Note that to reduce dependencies on the JDK we compute these

   // offsets at run-time.

   static int clazz_offset;

   static int name_offset;

   static int type_offset;

   static int slot_offset;

   static int modifiers_offset;

   static int signature_offset;

   static int annotations_offset;

   static void compute_offsets();

  public:

   // Allocation

   static Handle create(TRAPS);

   // Accessors

   static oop clazz(oop reflect);

   static void set_clazz(oop reflect, oop value);

   static oop name(oop field);

   static void set_name(oop field, oop value);

   static oop type(oop field);

   static void set_type(oop field, oop value);

   static int slot(oop reflect);

   static void set_slot(oop reflect, int value);

   static int modifiers(oop field);

   static void set_modifiers(oop field, int value);

   static bool has_signature_field();

   static oop signature(oop constructor);

   static void set_signature(oop constructor, oop value);

   static bool has_annotations_field();

   static oop annotations(oop constructor);

   static void set_annotations(oop constructor, oop value);

   static bool has_parameter_annotations_field();

   static oop parameter_annotations(oop method);

   static void set_parameter_annotations(oop method, oop value);

   static bool has_annotation_default_field();

   static oop annotation_default(oop method);

   static void set_annotation_default(oop method, oop value);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to sun.reflect.ConstantPool objects

 class sun_reflect_ConstantPool {

  private:

   // Note that to reduce dependencies on the JDK we compute these

   // offsets at run-time.

   static int _cp_oop_offset;

   static void compute_offsets();

  public:

   // Allocation

   static Handle create(TRAPS);

   // Accessors

   static oop cp_oop(oop reflect);

   static void set_cp_oop(oop reflect, oop value);

   static int cp_oop_offset() {

     return _cp_oop_offset;

   }

   // Debugging

   friend class JavaClasses;

 };

 // Interface to sun.reflect.UnsafeStaticFieldAccessorImpl objects

 class sun_reflect_UnsafeStaticFieldAccessorImpl {

  private:

   static int _base_offset;

   static void compute_offsets();

  public:

   static int base_offset() {

     return _base_offset;

   }

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang primitive type boxing objects:

 //  - java.lang.Boolean

 //  - java.lang.Character

 //  - java.lang.Float

 //  - java.lang.Double

 //  - java.lang.Byte

 //  - java.lang.Short

 //  - java.lang.Integer

 //  - java.lang.Long

 // This could be separated out into 8 individual classes.

 class java_lang_boxing_object: AllStatic {

  private:

   enum {

    hc_value_offset = 0

   };

   static int value_offset;

   static int long_value_offset;

   static oop initialize_and_allocate(BasicType type, TRAPS);

  public:

   // Allocation. Returns a boxed value, or NULL for invalid type.

   static oop create(BasicType type, jvalue* value, TRAPS);

   // Accessors. Returns the basic type being boxed, or T_ILLEGAL for invalid oop.

   static BasicType get_value(oop box, jvalue* value);

   static BasicType set_value(oop box, jvalue* value);

   static BasicType basic_type(oop box);

   static bool is_instance(oop box)                 { return basic_type(box) != T_ILLEGAL; }

   static bool is_instance(oop box, BasicType type) { return basic_type(box) == type; }

   static void print(oop box, outputStream* st)     { jvalue value;  print(get_value(box, &value), &value, st); }

   static void print(BasicType type, jvalue* value, outputStream* st);

   static int value_offset_in_bytes(BasicType type) {

     return ( type == T_LONG || type == T_DOUBLE ) ? long_value_offset :

                                                     value_offset;

   }

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.ref.Reference objects

 class java_lang_ref_Reference: AllStatic {

  public:

   enum {

    hc_referent_offset   = 0,

    hc_queue_offset      = 1,

    hc_next_offset       = 2,

    hc_discovered_offset = 3  // Is not last, see SoftRefs.

   };

   enum {

    hc_static_lock_offset    = 0,

    hc_static_pending_offset = 1

   };

   static int referent_offset;

   static int queue_offset;

   static int next_offset;

   static int discovered_offset;

   static int static_lock_offset;

   static int static_pending_offset;

   static int number_of_fake_oop_fields;

   // Accessors

   static oop referent(oop ref) {

     return ref->obj_field(referent_offset);

   }

   static void set_referent(oop ref, oop value) {

     ref->obj_field_put(referent_offset, value);

   }

   static void set_referent_raw(oop ref, oop value) {

     ref->obj_field_raw_put(referent_offset, value);

   }

   static HeapWord* referent_addr(oop ref) {

     return ref->obj_field_addr<HeapWord>(referent_offset);

   }

   static oop next(oop ref) {

     return ref->obj_field(next_offset);

   }

   static void set_next(oop ref, oop value) {

     ref->obj_field_put(next_offset, value);

   }

   static void set_next_raw(oop ref, oop value) {

     ref->obj_field_raw_put(next_offset, value);

   }

   static HeapWord* next_addr(oop ref) {

     return ref->obj_field_addr<HeapWord>(next_offset);

   }

   static oop discovered(oop ref) {

     return ref->obj_field(discovered_offset);

   }

   static void set_discovered(oop ref, oop value) {

     ref->obj_field_put(discovered_offset, value);

   }

   static void set_discovered_raw(oop ref, oop value) {

     ref->obj_field_raw_put(discovered_offset, value);

   }

   static HeapWord* discovered_addr(oop ref) {

     return ref->obj_field_addr<HeapWord>(discovered_offset);

   }

   // Accessors for statics

   static oop  pending_list_lock();

   static oop  pending_list();

   static HeapWord*  pending_list_addr();

 };

 // Interface to java.lang.ref.SoftReference objects

 class java_lang_ref_SoftReference: public java_lang_ref_Reference {

  public:

   enum {

    // The timestamp is a long field and may need to be adjusted for alignment.

    hc_timestamp_offset  = hc_discovered_offset + 1

   };

   enum {

    hc_static_clock_offset = 0

   };

   static int timestamp_offset;

   static int static_clock_offset;

   // Accessors

   static jlong timestamp(oop ref);

   // Accessors for statics

   static jlong clock();

   static void set_clock(jlong value);

 };

 // Interface to java.security.AccessControlContext objects

 class java_security_AccessControlContext: AllStatic {

  private:

   // Note that for this class the layout changed between JDK1.2 and JDK1.3,

   // so we compute the offsets at startup rather than hard-wiring them.

   static int _context_offset;

   static int _privilegedContext_offset;

   static int _isPrivileged_offset;

   static void compute_offsets();

  public:

   static oop create(objArrayHandle context, bool isPrivileged, Handle privileged_context, TRAPS);

   // Debugging/initialization

   friend class JavaClasses;

 };

 // Interface to java.lang.ClassLoader objects

 class java_lang_ClassLoader : AllStatic {

  private:

   enum {

    hc_parent_offset = 0

   };

   static int parent_offset;

  public:

   static oop parent(oop loader);

   static bool is_trusted_loader(oop loader);

   // Fix for 4474172

   static oop  non_reflection_class_loader(oop loader);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.System objects

 class java_lang_System : AllStatic {

  private:

   enum {

    hc_static_in_offset  = 0,

    hc_static_out_offset = 1,

    hc_static_err_offset = 2

   };

   static int offset_of_static_fields;

   static int  static_in_offset;

   static int static_out_offset;

   static int static_err_offset;

   static void compute_offsets();

  public:

   static int  in_offset_in_bytes();

   static int out_offset_in_bytes();

   static int err_offset_in_bytes();

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.StackTraceElement objects

 class java_lang_StackTraceElement: AllStatic {

  private:

   enum {

     hc_declaringClass_offset  = 0,

     hc_methodName_offset = 1,

     hc_fileName_offset   = 2,

     hc_lineNumber_offset = 3

   };

   static int declaringClass_offset;

   static int methodName_offset;

   static int fileName_offset;

   static int lineNumber_offset;

  public:

   // Setters

   static void set_declaringClass(oop element, oop value);

   static void set_methodName(oop element, oop value);

   static void set_fileName(oop element, oop value);

   static void set_lineNumber(oop element, int value);

   // Create an instance of StackTraceElement

   static oop create(methodHandle m, int bci, TRAPS);

   // Debugging

   friend class JavaClasses;

 };

 // Interface to java.lang.AssertionStatusDirectives objects

 class java_lang_AssertionStatusDirectives: AllStatic {

  private:

   enum {

     hc_classes_offset,

     hc_classEnabled_offset,

     hc_packages_offset,

     hc_packageEnabled_offset,

     hc_deflt_offset

   };

   static int classes_offset;

   static int classEnabled_offset;

   static int packages_offset;

   static int packageEnabled_offset;

   static int deflt_offset;

  public:

   // Setters

   static void set_classes(oop obj, oop val);

   static void set_classEnabled(oop obj, oop val);

   static void set_packages(oop obj, oop val);

   static void set_packageEnabled(oop obj, oop val);

   static void set_deflt(oop obj, bool val);

   // Debugging

   friend class JavaClasses;

 };

 class java_nio_Buffer: AllStatic {

  private:

   static int _limit_offset;

  public:

   static int  limit_offset();

   static void compute_offsets();

 };

 class sun_misc_AtomicLongCSImpl: AllStatic {

  private:

   static int _value_offset;

  public:

   static int  value_offset();

   static void compute_offsets();

 };

 class java_util_concurrent_locks_AbstractOwnableSynchronizer : AllStatic {

  private:

   static int  _owner_offset;

  public:

   static void initialize(TRAPS);

   static oop  get_owner_threadObj(oop obj);

 };

 // Interface to hard-coded offset checking

 class JavaClasses : AllStatic {

  private:

   static bool check_offset(const char *klass_name, int offset, const char *field_name, const char* field_sig) PRODUCT_RETURN0;

   static bool check_static_offset(const char *klass_name, int hardcoded_offset, const char *field_name, const char* field_sig) PRODUCT_RETURN0;

   static bool check_constant(const char *klass_name, int constant, const char *field_name, const char* field_sig) PRODUCT_RETURN0;

  public:

   static void compute_hard_coded_offsets();

   static void compute_offsets();

   static void check_offsets() PRODUCT_RETURN;

 };