--- old/src/share/classes/java/util/stream/DoubleStream.java 2014-07-15 17:26:42.000000000 -0700 +++ new/src/share/classes/java/util/stream/DoubleStream.java 2014-07-15 17:26:42.000000000 -0700 @@ -1,5 +1,5 @@ /* - * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved. + * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it @@ -470,10 +470,7 @@ * code is not necessarily equivalent to the summation computation * done by this method. * - *

If any stream element is a NaN or the sum is at any point a NaN - * then the sum will be NaN. - * - * The value of a floating-point sum is a function both + *

The value of a floating-point sum is a function both * of the input values as well as the order of addition * operations. The order of addition operations of this method is * intentionally not defined to allow for implementation @@ -485,6 +482,23 @@ * numerical sum compared to a simple summation of {@code double} * values. * + *

If any stream element is a NaN or the intermediate sum is at + * any point a NaN, then the final sum will be NaN. + * + * If the stream elements contain infinities of opposite sign, the + * final sum will be NaN. + * + * It is possible for intermediate sums of finite values to + * overflow into opposite-signed infinities; if that occurs, the + * final sum will be NaN even if the stream elements are all + * finite. + * + * If the exact sum is infinite, a properly-signed infinity is + * returned. + * + * If all the stream elements are zero, the sign of zero is + * not guaranteed to be preserved in the final sum. + * *

This is a terminal * operation. * @@ -555,9 +569,6 @@ * mean of elements of this stream, or an empty optional if this * stream is empty. * - * If any recorded value is a NaN or the sum is at any point a NaN - * then the average will be NaN. - * *

The average returned can vary depending upon the order in * which values are recorded. * @@ -565,6 +576,10 @@ * other technique to reduce the error bound in the {@link #sum * numerical sum} used to compute the average. * + *

This method can return a NaN or infinite result in the same + * kind of numerical situations as {@linkplain #sum() the sum} can + * be NaN or infinite, respectively. + * *

The average is a special case of a reduction. *