>>>> Alan’s point is that traversing using entries()/stream() always returns
>>>> the versioned entries (if any) rather than all entries, thus in a sense
>>>> filters.
>>>>
>>>> My assumption was the traversal should by default be consistent with a
>>>> calls to getEntry, thus:
>>>>
>>>> jarFile.stream().forEach(e -> {
>>>> JarEntry je = jarFile.getJarEntry(e.getName());
>>>> assert e.equals(je);
>>>> });
>>>>
>>>> There might need to be another stream method that returns all entries.
>>>>
>>> Right, I'm mostly just wondering if entries()/streams() should override the
>>> entries in the stream with versioned entries and filter out the
>>> META-INF/versions/ tree.
>> I don’t think so. That kind of behavior might be difficult to understand.
>> Returning all the entries provides some flexibility. One can write code
>> like this:
>>
>> jarfile.stream().map(JarEntry::getName).filter(s ->
>> !s.startsWith(“META-INF”)).map(JarFile::getJarEntry).etc
>>
>> to get the versioned results for any version you specify when constructing
>> the JarFile.
>
> The current specification treats those class files under meta-inf/releases
> like
> kind of "metadata" of those base entries. Ideally those files should not even
> be individual "files", but part of their corresponding entries. The consumer
> of
> the MR-Jar should not need to be aware of these version-ed entries at all to
> use
> this MR-jar file to load classes/resources. From this point of view, these
> entries
> probably should be "invisible" from entries()/stream(), when the jar file is
> opened
> with "version-enabled". And all returned entries should have all their "data"
> (size, csize, timestamps, crc ...) pointed to the corresponding version-ed
> entries,
> withe the only exception is the "name".
>
> On the other hand it might be desired to keep JarFile.entries()/stream() asis
> to
> match their "zip file" perspective, to return "all" raw entries. Then it
> might also
> be desired to have an alternative "versioned streamVersion()" …
It seems to that we have two reasonable alternatives: (1) return all entries,
and (2) return all entries except those under the “META-INF/versions/“
directory and for any entries returned, return their versioned equivalent if it
exists. If we choose alternative 2, we can still get alternative 1 by asking
for JarFile.super.entries() and JarFile.super.stream().
Or we can do it both ways, leaving entries()/stream() as is and adding two new
methods, versionedEntries() and versionedStream().
>
> something like
>
> public Stream<JarEntry> stream(Release r); ?
We should not parametrize the methods with a Release, because what does it mean
if we construct the JarFile with one Release but specify a different Release
for the stream argument. Parameterizing methods with a Release object feels
like we’re starting to slide down a slippery slope.
I think adding the two new methods is the “right” solution, but I’d like some
consensus here.
>
> -sherman
>
>
>
>
>>> If I've gone to trouble of specifying the a Release then it seems the right
>>> thing to do. On the other hand, it comes at a cost and there will be
>>> use-cases like "get the names of all entries" that would be more efficient
>>> to just build on the current entries()/stream(). I'm loath to suggest this
>>> might need a new method but it might be one of the options to consider
>>> here. Minimally there is a javadoc to specify on how these methods behave
>>> when the JAR is multi-release and opened by specifying a release.
>> How’s this?
>>
>> diff -r 68867430065b src/java.base/share/classes/java/util/jar/JarFile.java
>> --- a/src/java.base/share/classes/java/util/jar/JarFile.java Fri Jan 29
>> 12:34:44 2016 -0800
>> +++ b/src/java.base/share/classes/java/util/jar/JarFile.java Mon Feb 01
>> 09:48:05 2016 -0800
>> @@ -576,9 +576,11 @@
>> }
>>
>> /**
>> - * Returns an enumeration of the jar file entries.
>> + * Returns an enumeration of all the jar file entries. Constructing
>> this
>> + * JarFile with the {@link JarFile#JarFile(File, boolean, int, Release)}
>> + * constructor does not modify the behavior of this method.
>> *
>> - * @return an enumeration of the jar file entries
>> + * @return an enumeration of the all jar file entries
>> * @throws IllegalStateException
>> * may be thrown if the jar file has been closed
>> */
>> @@ -587,11 +589,13 @@
>> }
>>
>> /**
>> - * Returns an ordered {@code Stream} over the jar file entries.
>> + * Returns an ordered {@code Stream} over all the jar file entries.
>> * Entries appear in the {@code Stream} in the order they appear in
>> - * the central directory of the jar file.
>> + * the central directory of the jar file. Constructing this
>> + * JarFile with the {@link JarFile#JarFile(File, boolean, int, Release)}
>> + * constructor does not modify the behavior of this method.
>> *
>> - * @return an ordered {@code Stream} of entries in this jar file
>> + * @return an ordered {@code Stream} of all entries in this jar file
>> * @throws IllegalStateException if the jar file has been closed
>> * @since 1.8
>> */
