src/java.base/share/classes/jdk/internal/misc/Unsafe.java

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

*** 952,961 ****
--- 952,980 ----
  
          return objectFieldOffset0(f);
      }
  
      /**
+      * Reports the location of the field with a given name in the storage
+      * allocation of its class.
+      *
+      * @throws NullPointerException if any parameter is {@code null}.
+      * @throws InternalError if there is no field named {@code name} declared
+      *         in class {@code c}, i.e., if {@code c.getDeclaredField(name)}
+      *         would throw {@code java.lang.NoSuchFieldException}.
+      *
+      * @see #objectFieldOffset(Field)
+      */
+     public long objectFieldOffset(Class<?> c, String name) {
+         if (c == null || name == null) {
+             throw new NullPointerException();
+         }
+ 
+         return objectFieldOffset1(c, name);
+     }
+ 
+     /**
       * Reports the location of a given static field, in conjunction with {@link
       * #staticFieldBase}.
       * <p>Do not expect to perform any sort of arithmetic on this offset;
       * it is just a cookie which is passed to the unsafe heap memory accessors.
       *
*** 3683,3692 ****
--- 3702,3712 ----
      private native void setMemory0(Object o, long offset, long bytes, byte value);
      @HotSpotIntrinsicCandidate
      private native void copyMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes);
      private native void copySwapMemory0(Object srcBase, long srcOffset, Object destBase, long destOffset, long bytes, long elemSize);
      private native long objectFieldOffset0(Field f);
+     private native long objectFieldOffset1(Class<?> c, String name);
      private native long staticFieldOffset0(Field f);
      private native Object staticFieldBase0(Field f);
      private native boolean shouldBeInitialized0(Class<?> c);
      private native void ensureClassInitialized0(Class<?> c);
      private native int arrayBaseOffset0(Class<?> arrayClass);