src/java.base/share/classes/java/util/zip/ZStreamRef.java

*** 23,46 ****
   * questions.
   */
  
  package java.util.zip;
  
  /**
!  * A reference to the native zlib's z_stream structure.
   */
  
! class ZStreamRef {
! 
!     private volatile long address;
!     ZStreamRef (long address) {
!         this.address = address;
      }
  
      long address() {
          return address;
      }
  
!     void clear() {
          address = 0;
      }
  }
--- 23,113 ----
   * questions.
   */
  
  package java.util.zip;
  
+ import java.util.function.LongConsumer;
+ import java.util.function.LongSupplier;
+ import java.lang.ref.Cleaner.Cleanable;
+ import jdk.internal.ref.CleanerFactory;
+ 
  /**
!  * A reference to the native zlib's z_stream structure. It also
!  * serves as the "cleaner" to clean up the native resource when
!  * the deflater or infalter is ended, closed or cleaned.
   */
+ class ZStreamRef implements Runnable {
  
!     private LongConsumer end;
!     private long address;
!     private final Cleanable cleanable;
! 
!     private ZStreamRef (Object owner, LongSupplier addr, LongConsumer end) {
!         this.cleanable = CleanerFactory.cleaner().register(owner, this);
!         this.end = end;
!         this.address = addr.getAsLong();
      }
  
      long address() {
          return address;
      }
  
!     void clean() {
!         cleanable.clean();
!     }
! 
!     public synchronized void run() {
!         long addr = address;
          address = 0;
+         if (addr != 0) {
+             end.accept(addr);
+         }
+     }
+ 
+     private ZStreamRef (LongSupplier addr, LongConsumer end) {
+         this.cleanable = null;
+         this.end = end;
+         this.address = addr.getAsLong();
+     }
+ 
+     /*
+      * If {@code Inflater/Deflater} has been subclassed and the {@code end} method
+      * is overridden, uses {@code finalizer} mechanism for resource cleanup. So
+      * {@code end} method can be called when the {@code Inflater/Deflater} is
+      * unreachable. This mechanism will be removed when the {@code finalize} method
+      * is removed from {@code Inflater/Deflater}.
+      */
+     static ZStreamRef get(Object owner, LongSupplier addr, LongConsumer end) {
+         Class<?> clz = owner.getClass();
+         while (clz != Deflater.class && clz != Inflater.class) {
+             try {
+                 clz.getDeclaredMethod("end");
+                 return new FinalizableZStreamRef(owner, addr, end);
+             } catch (NoSuchMethodException nsme) {}
+             clz = clz.getSuperclass();
+         }
+         return new ZStreamRef(owner, addr, end);
+     }
+ 
+     private static class FinalizableZStreamRef extends ZStreamRef {
+         Object owner;
+ 
+         FinalizableZStreamRef (Object owner, LongSupplier addr, LongConsumer end) {
+             super(addr, end);
+             this.owner = owner;
+         }
+ 
+         @Override
+         void clean() {
+             run();
+         }
+ 
+         @Override
+         @SuppressWarnings("deprecation")
+         protected void finalize() {
+             if (owner instanceof Inflater)
+                 ((Inflater)owner).end();
+             else
+                 ((Deflater)owner).end();
+         }
      }
  }