src/java.base/share/classes/jdk/internal/reflect/UnsafeFieldAccessorImpl.java

*** 25,34 ****
--- 25,36 ----
  
  package jdk.internal.reflect;
  
  import java.lang.reflect.Field;
  import java.lang.reflect.Modifier;
+ import java.util.Objects;
+ 
  import jdk.internal.misc.Unsafe;
  
  /** Base class for jdk.internal.misc.Unsafe-based FieldAccessors. The
      observation is that there are only nine types of fields from the
      standpoint of reflection code: the eight primitive types and
*** 36,68 ****
      memory and loading time for the dynamically-generated
      FieldAccessors. */
  
  abstract class UnsafeFieldAccessorImpl extends FieldAccessorImpl {
      static final Unsafe unsafe = Unsafe.getUnsafe();
  
      protected final Field   field;
      protected final long    fieldOffset;
      protected final boolean isFinal;
!     protected final boolean isFlattened;
  
      UnsafeFieldAccessorImpl(Field field) {
          this.field = field;
          if (Modifier.isStatic(field.getModifiers()))
!             fieldOffset = unsafe.staticFieldOffset(field);
          else
!             fieldOffset = unsafe.objectFieldOffset(field);
!         isFinal = Modifier.isFinal(field.getModifiers());
!         isFlattened = ReflectionFactory.langReflectAccess().isFlattened(field);
      }
  
      protected void ensureObj(Object o) {
          // NOTE: will throw NullPointerException, as specified, if o is null
          if (!field.getDeclaringClass().isAssignableFrom(o.getClass())) {
              throwSetIllegalArgumentException(o);
          }
      }
  
      private String getQualifiedFieldName() {
        return field.getDeclaringClass().getName() + "." +field.getName();
      }
  
      protected IllegalArgumentException newGetIllegalArgumentException(String type) {
--- 38,105 ----
      memory and loading time for the dynamically-generated
      FieldAccessors. */
  
  abstract class UnsafeFieldAccessorImpl extends FieldAccessorImpl {
      static final Unsafe unsafe = Unsafe.getUnsafe();
+     private static final int FLATTENABLE = 0x01;
+     private static final int FLATTENED   = 0x10;
+     private static final int NULLABLE    = 0x100;
  
      protected final Field   field;
      protected final long    fieldOffset;
      protected final boolean isFinal;
!     protected final int     flags;
  
      UnsafeFieldAccessorImpl(Field field) {
          this.field = field;
          if (Modifier.isStatic(field.getModifiers()))
!             this.fieldOffset = unsafe.staticFieldOffset(field);
          else
!             this.fieldOffset = unsafe.objectFieldOffset(field);
!         this.isFinal = Modifier.isFinal(field.getModifiers());
! 
!         int flags = 0;
!         if (ReflectionFactory.langReflectAccess().isFlattenable(field))
!             flags |= FLATTENABLE;
!         if (ReflectionFactory.langReflectAccess().isFlattened(field))
!             flags |= FLATTENED;
!         if (ReflectionFactory.langReflectAccess().isNullable(field))
!             flags |= NULLABLE;
!         this.flags = flags;
      }
  
      protected void ensureObj(Object o) {
          // NOTE: will throw NullPointerException, as specified, if o is null
          if (!field.getDeclaringClass().isAssignableFrom(o.getClass())) {
              throwSetIllegalArgumentException(o);
          }
      }
  
+     protected boolean isFlattenable() {
+         return (flags & FLATTENABLE) == FLATTENABLE;
+     }
+ 
+     protected boolean isFlattened() {
+         return (flags & FLATTENED) == FLATTENED;
+     }
+ 
+     protected boolean isNullable() {
+         return (flags & NULLABLE) == NULLABLE;
+     }
+ 
+     protected Object checkValue(Object value) {
+         if (!isNullable() && value == null)
+             throw new NullPointerException(field + " cannot be set to null");
+ 
+         if (value != null) {
+             if (!field.getType().isAssignableFrom(value.getClass())) {
+                 throwSetIllegalArgumentException(value);
+             }
+         }
+         return value;
+     }
+ 
      private String getQualifiedFieldName() {
        return field.getDeclaringClass().getName() + "." +field.getName();
      }
  
      protected IllegalArgumentException newGetIllegalArgumentException(String type) {