[jira] [Created] (COMPRESS-375) Allow the clients of ParallelScatterZipCreator to provide ZipArchiveEntryRequestSupplier

["Plamen Totev (JIRA)" <ji...@apache.org>]

Plamen Totev created COMPRESS-375:
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             Summary: Allow the clients of ParallelScatterZipCreator to provide ZipArchiveEntryRequestSupplier
                 Key: COMPRESS-375
                 URL: https://issues.apache.org/jira/browse/COMPRESS-375
             Project: Commons Compress
          Issue Type: Improvement
          Components: Archivers
            Reporter: Plamen Totev


Currently clients of {{ParallelScatterZipCreator}} could provide {{ZipArchiveEntry}} and {{InputStreamSupplier}} through {{ParallelScatterZipCreator#addArchiveEntry}}. From those two a {{ZipArchiveEntryRequest}} is created. Providing {{InputStreamSupplier}} solves the problem with opening too many files - streams are opened just-in-time - when an entry is  compressed, not when it's submitted.

But there are use cases when the stream may contain information about the {{ZipArchiveEntry}}. In those cases creating {{ZipArchiveEntry}} before the {{InputStream}} is opened won't work. If there is an option to supply both {{ZipArchiveEntry}} and {{InputStreamSupplier}} ({{ZipArchiveEntryRequest}}), this will solve the issue.

There is a bug in Plexus Archiver (https://github.com/codehaus-plexus/plexus-archiver/issues/53) that is example for such use case. Plexus Archiver have option that allows entries that are already zip files to be stored instead of compressed ({{AbstractZipArchiver.recompressAddedZips}}). To detect if given entry is zip archive, {{AbstractZipArchiver}} should read the first several bytes of the stream. So creating {{ZipArchiveEntry}} before the stream is opened is not useful - the compress mode is not known. Opening the stream when the  {{ZipArchiveEntry}} is created won't work either. Because you can add entries to {{ParallelScatterZipCreator}} a lot faster than you could compress them you could open too many files very fast. And I don't think opening and closing the stream is an option as such operations could be relatively expensive in the general case. But if it could supply both the {{ZipArchiveEntry}} and the {{InputStream}} just-in-time (by passing {{ZipArchiveEntryRequestSupplier}} to {{ParallelScatterZipCreator}}) then the problem is solved.

What do you think. Does the addition of {{ParallelScatterZipCreator#addArchiveEntry(ZipArchiveEntryRequestSupplier)}} make sense?



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