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

@@ -65,16 +65,23 @@
  * } catch (java.util.zip.DataFormatException ex) {
  *     // handle
  * }
  * </pre></blockquote>
  *
+ * @apiNote
+ * To release resources used by this {@code Deflater}, the {@link #end()} method
+ * should be called explicitly. Subclasses are responsible for the cleanup of resources
+ * acquired by the subclass. Subclasses that override {@link #finalize()} in order
+ * to perform cleanup should be modified to use alternative cleanup mechanisms such
+ * as {@link java.lang.ref.Cleaner} and remove the overriding {@code finalize} method.
+ *
  * @see         Inflater
  * @author      David Connelly
  * @since 1.1
  */
-public
-class Deflater {
+
+public class Deflater {
 
     private final ZStreamRef zsRef;
     private byte[] buf = new byte[0];
     private int off, len;
     private int level, strategy;

@@ -167,11 +174,13 @@
      * @param nowrap if true then use GZIP compatible compression
      */
     public Deflater(int level, boolean nowrap) {
         this.level = level;
         this.strategy = DEFAULT_STRATEGY;
-        this.zsRef = new ZStreamRef(init(level, DEFAULT_STRATEGY, nowrap));
+        this.zsRef = ZStreamRef.get(this,
+                () -> init(level, DEFAULT_STRATEGY, nowrap),
+                Deflater::end);
     }
 
     /**
      * Creates a new compressor using the specified compression level.
      * Compressed data will be generated in ZLIB format.

@@ -532,42 +541,41 @@
         }
     }
 
     /**
      * Closes the compressor and discards any unprocessed input.
+     *
      * This method should be called when the compressor is no longer
-     * being used, but will also be called automatically by the
-     * finalize() method. Once this method is called, the behavior
-     * of the Deflater object is undefined.
+     * being used. Once this method is called, the behavior of the
+     * Deflater object is undefined.
      */
     public void end() {
         synchronized (zsRef) {
-            long addr = zsRef.address();
-            zsRef.clear();
-            if (addr != 0) {
-                end(addr);
+            zsRef.clean();
                 buf = null;
             }
         }
-    }
 
     /**
      * Closes the compressor when garbage is collected.
      *
-     * @deprecated The {@code finalize} method has been deprecated.
-     *     Subclasses that override {@code finalize} in order to perform cleanup
-     *     should be modified to use alternative cleanup mechanisms and
-     *     to remove the overriding {@code finalize} method.
-     *     When overriding the {@code finalize} method, its implementation must explicitly
-     *     ensure that {@code super.finalize()} is invoked as described in {@link Object#finalize}.
-     *     See the specification for {@link Object#finalize()} for further
-     *     information about migration options.
-     */
-    @Deprecated(since="9")
-    protected void finalize() {
-        end();
-    }
+     * @implSpec
+     * If this {@code Deflater} has been subclassed and the {@code end} method
+     * has been overridden, the {@code end} method will be called when the
+     * inflater is unreachable.
+     *
+     * @deprecated The {@code finalize} method has been deprecated and
+     *     implemented as a no-op. Subclasses that override {@code finalize}
+     *     in order to perform cleanup should be modified to use alternative
+     *     cleanup mechanisms and to remove the overriding {@code finalize}
+     *     method. The recommended cleanup for compressor is to explicitly
+     *     call {@code end} method when it is no longer in use. If the
+     *     {@code end} is not invoked explicitly the resource of the compressor
+     *     will be released when the instance becomes phantom-reachable.
+     */
+    @Deprecated(since="9", forRemoval=true)
+    protected void finalize() {}
 
     private void ensureOpen() {
         assert Thread.holdsLock(zsRef);
         if (zsRef.address() == 0)
             throw new NullPointerException("Deflater has been closed");