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

rev 7573 : 8015315: Stream.concat methods
Contributed-by: brian.goetz@oracle.com, henry.jen@oracle.com

*** 798,803 ****
--- 798,825 ----
          } else {
              return StreamSupport.intStream(
                      new Streams.RangeIntSpliterator(startInclusive, endInclusive, true));
          }
      }
+ 
+     /**
+      * Creates a lazy concatenated {@code IntStream} whose elements are all the
+      * elements of a first {@code IntStream} succeeded by all the elements of the
+      * second {@code IntStream}. The resulting stream is ordered if both
+      * of the input streams are ordered, and parallel if either of the input
+      * streams is parallel.
+      *
+      * @param a the first stream
+      * @param b the second stream to concatenate on to end of the first stream
+      * @return the concatenation of the two streams
+      */
+     public static IntStream concat(IntStream a, IntStream b) {
+         Objects.requireNonNull(a);
+         Objects.requireNonNull(b);
+ 
+         Spliterator.OfInt split = new Streams.ConcatSpliterator.OfInt(
+                 a.spliterator(), b.spliterator());
+         return (a.isParallel() || b.isParallel())
+                ? StreamSupport.intParallelStream(split)
+                : StreamSupport.intStream(split);
+     }
  }