src/share/classes/java/util/stream/BaseStream.java

rev 7633 : 8017513: Support for closeable streams
Reviewed-by:
Contributed-by: brian.goetz@oracle.com

*** 22,31 ****
--- 22,32 ----
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  package java.util.stream;
  
+ import java.util.MayHoldCloseableResource;
  import java.util.Iterator;
  import java.util.Spliterator;
  
  /**
   * Base interface for stream types such as {@link Stream}, {@link IntStream},
*** 33,43 ****
   *
   * @param <T> type of stream elements
   * @param <S> type of stream implementing {@code BaseStream}
   * @since 1.8
   */
! public interface BaseStream<T, S extends BaseStream<T, S>> {
      /**
       * Returns an iterator for the elements of this stream.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
--- 34,45 ----
   *
   * @param <T> type of stream elements
   * @param <S> type of stream implementing {@code BaseStream}
   * @since 1.8
   */
! public interface BaseStream<T, S extends BaseStream<T, S>>
!         extends MayHoldCloseableResource {
      /**
       * Returns an iterator for the elements of this stream.
       *
       * <p>This is a <a href="package-summary.html#StreamOps">terminal
       * operation</a>.
*** 101,106 ****
--- 103,122 ----
       * operation</a>.
       *
       * @return an unordered stream
       */
      S unordered();
+ 
+     /**
+      * Returns an equivalent stream with an additional close handler.  Close
+      * handlers are run when the {@link MayHoldCloseableResource#close()} method
+      * is called on the stream, and are executed in the order they were
+      * added.  All close handlers are run, even if earlier close handlers throw
+      * exceptions.  If any close handler throws an exception, the first
+      * exception thrown will be relayed to the caller of {@code close()}, with
+      * any remaining exceptions added to that exception as suppressed exceptions.
+      *
+      * @param closeHandler A task to execute when the stream is closed
+      * @return a stream with a handler that is run if the stream is closed
+      */
+     S onClose(Runnable closeHandler);
  }