src/java.base/share/classes/java/lang/Class.java

rev 17358 : 8182487: Add Unsafe.objectFieldOffset(Class, String)
Reviewed-by: dsimms

*** 2861,2882 ****
          private static final long annotationTypeOffset;
          // offset of Class.annotationData instance field
          private static final long annotationDataOffset;
  
          static {
!             Field[] fields = Class.class.getDeclaredFields0(false); // bypass caches
!             reflectionDataOffset = objectFieldOffset(fields, "reflectionData");
!             annotationTypeOffset = objectFieldOffset(fields, "annotationType");
!             annotationDataOffset = objectFieldOffset(fields, "annotationData");
          }
  
!         private static long objectFieldOffset(Field[] fields, String fieldName) {
!             Field field = searchFields(fields, fieldName);
!             if (field == null) {
!                 throw new Error("No " + fieldName + " field found in java.lang.Class");
!             }
!             return unsafe.objectFieldOffset(field);
          }
  
          static <T> boolean casReflectionData(Class<?> clazz,
                                               SoftReference<ReflectionData<T>> oldData,
                                               SoftReference<ReflectionData<T>> newData) {
--- 2861,2877 ----
          private static final long annotationTypeOffset;
          // offset of Class.annotationData instance field
          private static final long annotationDataOffset;
  
          static {
!             reflectionDataOffset = objectFieldOffset("reflectionData");
!             annotationTypeOffset = objectFieldOffset("annotationType");
!             annotationDataOffset = objectFieldOffset("annotationData");
          }
  
!         private static long objectFieldOffset(String fieldName) {
!             return unsafe.objectFieldOffset(Class.class, fieldName);
          }
  
          static <T> boolean casReflectionData(Class<?> clazz,
                                               SoftReference<ReflectionData<T>> oldData,
                                               SoftReference<ReflectionData<T>> newData) {