> This change introduces a new terminal operation on Stream. This looks like a > convenience method for Stream.collect(Collectors.toList()) or > Stream.collect(Collectors.toUnmodifiableList()), but it's not. Having this > method directly on Stream enables it to do what can't easily by done by a > Collector. In particular, it allows the stream to deposit results directly > into a destination array (even in parallel) and have this array be wrapped in > an unmodifiable List without copying. > > In the past we've kept most things from the Collections Framework as > implementations of Collector, not directly on Stream, whereas only > fundamental things (like toArray) appear directly on Stream. This is true of > most Collections, but it does seem that List is special. It can be a thin > wrapper around an array; it can handle generics better than arrays; and > unlike an array, it can be made unmodifiable (shallowly immutable); and it > can be value-based. See John Rose's comments in the bug report: > > https://bugs.openjdk.java.net/browse/JDK-8180352?focusedCommentId=14133065&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14133065 > > This operation is null-tolerant, which matches the rest of Streams. This > isn't specified, though; a general statement about null handling in Streams > is probably warranted at some point. > > Finally, this method is indeed quite convenient (if the caller can deal with > what this operation returns), as collecting into a List is the most common > stream terminal operation.
Stuart Marks has updated the pull request incrementally with one additional commit since the last revision: Add comment and assert regarding array class; use switch expression. ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/1026/files - new: https://git.openjdk.java.net/jdk/pull/1026/files/15beacd2..bd890ae5 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=1026&range=03 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=1026&range=02-03 Stats: 20 lines in 1 file changed: 4 ins; 4 del; 12 mod Patch: https://git.openjdk.java.net/jdk/pull/1026.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/1026/head:pull/1026 PR: https://git.openjdk.java.net/jdk/pull/1026
