RFR: 8276764: Enable deterministic file content ordering for Jar and Jmod

[Mandy Chung]

On Mon, 15 Nov 2021 18:47:34 GMT, Andrew Leonard <aleonard at openjdk.org> wrote:

> Both jar and jmod utilise java.io file operations whose methods define no ordering of the return file lists, and in fact rely on OS query file ordering, which can differ by underlying OS architecture.
> This PR adds sort processing to the creation of such jar's and jmod's to enable a deterministic content ordering.
> 
> Signed-off-by: Andrew Leonard <anleonar at redhat.com>

src/jdk.jartool/share/classes/sun/tools/jar/Main.java line 131:

> 129:     // There's also a files array per version
> 130:     // Use a LinkedHashMap to keep original insertion ordering
> 131:     Map<Integer,String[]> filesMap = new LinkedHashMap<>();

The entries of `filesMap` is sorted by the version.   Is the value of each entry already sorted?  Does that matter?   It's unclear to me since `expand` is called for each entry's value:


    private void expand() throws IOException {
        for (int version : filesMap.keySet()) {
            String[] files = filesMap.get(version);
            expand(null, files, pathsMap.get(version), version);
        }
    }

src/jdk.jlink/share/classes/jdk/tools/jmod/JmodTask.java line 803:

> 801:                     out.writeEntry(in, section, name);
> 802:                 }
> 803:             }

jmod change is okay.

test/jdk/tools/jar/ContentOrder.java line 79:

> 77:     @Test
> 78:     public void test1() throws IOException {
> 79:         mkdir("testjar/Ctest1 testjar/Btest2/subdir1 testjar/Atest3");

I suggest to make `mkdir` and `touch` to take a vararg of String or Path and the method body concatenates the input strings to build the command line.

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PR: https://git.openjdk.java.net/jdk/pull/6395