RFR: JDK-8080511 - Refresh of jimage support

[Jean-Francois Denise]

Hi Paul,

On 19 Jun 2015, at 16:39, Paul Sandoz <paul.sandoz at oracle.com> wrote:

> 
> On Jun 18, 2015, at 2:08 AM, Jim Laskey (Oracle) <james.laskey at oracle.com> wrote:
> 
>> https://bugs.openjdk.java.net/browse/JDK-8080511
>> 
>> This is an long overdue refresh of the jimage support in the JDK9-dev repo.  This includes native support for reading jimage files, improved jrt-fs (java runtime file system) support for retrieving modules and packages from the runtime, and improved performance for langtools in the presence of jrt-fs.
>> 
>> http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-top <http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-top>
>> http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-jdk <http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-jdk>
> 
> I eyeballed the JDK changes. Just two thing:
> 
> make/src/classes/build/tools/module/ModuleArchive.java
> 
>  90     @Override
>  91     public Stream<Entry> entries() {
>  92         List<Entry> entries = new ArrayList<>();
>  93         try {
>  94             if (classes != null)
>  95                 Files.walk(classes)
>  96                         .sorted()
>  97                         .filter(p -> !Files.isDirectory(p)
>  98                                 && !classes.relativize(p).toString().startsWith("_the.")
>  99                                 && !classes.relativize(p).toString().equals("javac_state"))
> 100                         .map(p -> toEntry(p, classes, EntryType.CLASS_OR_RESOURCE))
> 101                         .forEach(entries::add);
> 102             if (cmds != null)
> 103                 Files.walk(cmds)
> 104                         .filter(p -> !Files.isDirectory(p))
> 105                         .map(p -> toEntry(p, cmds, EntryType.NATIVE_CMD))
> 106                         .forEach(entries::add);
> 107             if (libs != null)
> 108                 Files.walk(libs)
> 109                         .filter(p -> !Files.isDirectory(p))
> 110                         .map(p -> toEntry(p, libs, EntryType.NATIVE_LIB))
> 111                         .forEach(entries::add);
> 112             if (configs != null)
> 113                 Files.walk(configs)
> 114                         .filter(p -> !Files.isDirectory(p))
> 115                         .map(p -> toEntry(p, configs, EntryType.CONFIG))
> 116                         .forEach(entries::add);
> 117         } catch (IOException ioe) {
> 118             throw new UncheckedIOException(ioe);
> 119         }
> 120         return entries.stream();
> 121     }
> 
> You can use collect(toList())

==> OK collect used. In addition, filter first then sort, tryWithResource for 4 Files stream.

> 
> In general the contract for Archive.entries probably has to say the stream needs to be closed after use since it might cover lazy I/O based resources, so callers will need to use a try-with-resources block.

==> Added a note in javadoc, implemented explicit close for non lazy streams, added missing tryWithResource. Added a comment on what should be done in ModuleArchive to keep laziness.
> 
> Paul.

Thanks.

> 
>> http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-hotspot <http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-hotspot>
>> http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-langtools <http://cr.openjdk.java.net/~jlaskey/hs-rt-jimage/webrev-langtools>
>> 
>> 
>> Details:
>> 
>> - jrt-fs provides access, via the nio FileSystem API, to the classes in a .jimage file, organized by module or by package.
>> - Shared code for jimage support converted to native.  Currently residing in hotspot, but will migrate to it’s own jdk library https://bugs.openjdk.java.net/browse/JDK-8087181 <https://bugs.openjdk.java.net/browse/JDK-8087181>
>> - A new archive abstraction for class/resource sources.
>> - java based implementation layer for jimage reading to allow backport to JDK8 (jrt-fs.jar - IDE support.)
>> - JNI support for jimage into hotspot.
>> - White box tests written to exercise native jimage support.
>> 
>