--- old/src/hotspot/share/classfile/javaClasses.hpp	2018-04-20 00:46:45.000000000 +0100
+++ new/src/hotspot/share/classfile/javaClasses.hpp	2018-04-20 00:46:45.000000000 +0100
@@ -309,6 +309,7 @@
   static int _stillborn_offset;
   static int _stackSize_offset;
   static int _tid_offset;
+  static int _continuation_offset;
   static int _thread_status_offset;
   static int _park_blocker_offset;
   static int _park_event_offset ;
@@ -349,6 +350,9 @@
   static jlong stackSize(oop java_thread);
   // Thread ID
   static jlong thread_id(oop java_thread);
+  // Continuation
+  static oop  continuation(oop java_thread);
+  static void set_continuation(oop java_thread, oop continuation);
 
   // Blocker object responsible for thread parking
   static oop park_blocker(oop java_thread);
@@ -944,6 +948,60 @@
   static void serialize(SerializeClosure* f) NOT_CDS_RETURN;
 };
 
+// Interface to java.lang.Continuation objects
+class java_lang_Continuation: AllStatic {
+  friend class JavaClasses;
+ private:
+  static void compute_offsets();
+  static Method* get_stack_method();
+public:
+ enum {
+  hc_fp_offset   = 0,
+  hc_sp_offset   = 11,
+  hc_entrySP_offset = 1,
+  hc_entryFP_offset = 3,
+  hc_target_offset   = 13,
+  hc_parent_offset   = 14,
+  hc_stack_offset    = 15,
+ };
+ static int scope_offset;
+ static int target_offset;
+ static int parent_offset;
+ static int entrySP_offset;
+ static int entryFP_offset;
+ static int entryPC_offset;
+ static int stack_offset;
+ static int refStack_offset;
+ static int stackSize_offset;
+ static int fp_offset;
+ static int sp_offset;
+ static int pc_offset;
+ static int refSP_offset;
+ static Method* stack_method;
+ // Accessors
+ static inline oop scope(oop ref);
+ static inline oop target(oop ref);
+ static inline oop parent(oop ref);
+ static inline typeArrayOop stack(oop ref);
+ static inline objArrayOop refStack(oop ref);
+ static inline jint fp(oop ref);
+ static inline void set_fp(oop ref, const jint i);
+ static inline jint sp(oop ref);
+ static inline void set_sp(oop ref, const jint i);
+ static inline void* pc(oop ref);
+ static inline void  set_pc(oop ref, const void* pc);
+ static inline jint refSP(oop ref);
+ static inline void set_refSP(oop ref, jint i);
+ static inline address entryFP(oop ref);
+ static inline address entrySP(oop ref);
+ static inline address entryPC(oop ref);
+ static inline int stack_size(oop ref);
+ static inline void* stack_base(oop ref);
+ static inline HeapWord* refStack_base(oop ref);
+ static bool on_local_stack(oop ref, address adr);
+
+};
+
 // Interface to java.lang.invoke.MethodHandle objects
 
 class MethodHandleEntry;