RFR: 8306914: Implement JEP 458: Launch Multi-File Source-Code Programs [v7]

Fri Dec 1 13:02:38 UTC 2023

On Fri, 1 Dec 2023 12:41:16 GMT, Christian Stein <cstein at openjdk.org> wrote:

>> Please review this change set implementing [JEP 458](https://openjdk.org/jeps/458) "Launch Multi-File Source-Code Programs" by introducing a new entry-point `SourceLauncher` in package `com.sun.tools.javac.launcher` of module `jdk.compiler`. The former `Main` entry-point is kept as-is in order to preserve (and possibly fall back to) existing behaviour of launching single-file source-code programs.
>> 
>> The code of the new entry-point and other new classes introduced by this pull request is based on the original implementation. It extends it to dynamically resolve required types "on-the-fly" using an in-memory class loader capable to compile Java source files - applying a strict name-based pattern as described in the JEP.
>> 
>> To support modular programs with user-provided additional modules (launched for example via `java -p . pkg/Prog1.java`) `ALL-MODULE-PATH` is now also part of the implicit list of modules name in source launch mode.
>> 
>> ### Open Ends
>> 
>> - [ ] Tests with [JEP 463: Implicitly Declared Classes and Instance Main Methods (Second Preview))](https://bugs.openjdk.org/browse/JDK-8315398)
>> 
>> ### OpenJDK's Demo Programs
>> 
>> OpenJDK's demo programs can be found in the [src/demo/share/jfc](https://github.com/openjdk/jdk/tree/master/src/demo/share/jfc) directory. These multi-file source-code programs can be launched via `java ${PROGRAM}` once this implementation is integrated; with `${PROGRAM}` being one of the following files:
>> 
>> - [x] `src/demo/share/jfc/CodePointIM/CodePointIM.java`
>> - [x] `src/demo/share/jfc/FileChooserDemo/FileChooserDemo.java`
>> - [x] `src/demo/share/jfc/Font2DTest/Font2DTest.java`
>> - [x] `src/demo/share/jfc/J2Ddemo/java2d/J2Ddemo.java`
>> - [x] `src/demo/share/jfc/Metalworks/Metalworks.java`
>> - [x] `src/demo/share/jfc/Notepad/Notepad.java`
>> - [x] `src/demo/share/jfc/SampleTree/SampleTree.java`
>> - [ ] `src/demo/share/jfc/Stylepad/Stylepad.java` — requires `src/demo/share/jfc/Notepad/Notepad.java`
>> - [x] `src/demo/share/jfc/SwingSet2/SwingSet2.java`
>> - [ ] `src/demo/share/jfc/TableExample/TableExample.java` — requires a database driver on the class path
>> - [ ] `src/demo/share/jfc/TableExample/TableExample2.java` —  requires a database driver on the class path
>> - [x] `src/demo/share/jfc/TableExample/TableExample3.java`
>> - [x] `src/demo/share/jfc/TableExample/TableExample4.java`
>> - [x] `src/demo/share/jfc/TransparentRuler/transparentruler/Ruler.java`
>
> Christian Stein has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update test for implicit classes
>   
>   Preview notes normally emitted by `javac` are
>   suppressed now, as they contain hints that
>   does not apply to the source launcher and will
>   lead to errors. For example: `-Xlint:preview`

Just nits. Nice work.

src/jdk.compiler/share/classes/com/sun/tools/javac/launcher/MemoryClassLoader.java line 59:

> 57:  * as any like-named classes that might be found on the application class path.)
> 58:  *
> 59:  * <p><b>This is NOT part of any supported API.

< strong > instead of < b >

src/jdk.compiler/share/classes/com/sun/tools/javac/launcher/MemoryContext.java line 68:

> 66:  * If you write code that depends on this, you do so at your own
> 67:  * risk.  This code and its internal interfaces are subject to change
> 68:  * or deletion without notice.</b></p>

< strong > instead of < b >

src/jdk.compiler/share/classes/com/sun/tools/javac/launcher/MemoryFileManager.java line 50:

> 48:  * If you write code that depends on this, you do so at your own
> 49:  * risk.  This code and its internal interfaces are subject to change
> 50:  * or deletion without notice.</b></p>

< strong >

src/jdk.compiler/share/classes/com/sun/tools/javac/launcher/MemoryModuleFinder.java line 49:

> 47: 
> 48: import jdk.internal.module.Resources;
> 49: 

This is NOT part of any supported API. ...

src/jdk.compiler/share/classes/com/sun/tools/javac/launcher/ProgramDescriptor.java line 48:

> 46:  * risk.  This code and its internal interfaces are subject to change
> 47:  * or deletion without notice.</b></p>
> 48:  */

< strong >

src/jdk.compiler/share/classes/com/sun/tools/javac/launcher/Result.java line 36:

> 34:  * @param classNames the names of classes compiled into memory.
> 35:  */
> 36: public record Result(Class<?> programClass, Set<String> classNames) {}

This is NOT part of any supported API. ...

src/jdk.compiler/share/classes/com/sun/tools/javac/launcher/SourceLauncher.java line 54:

> 52:  * risk.  This code and its internal interfaces are subject to change
> 53:  * or deletion without notice.</b></p>
> 54:  */

< strong >

-------------

Marked as reviewed by jlaskey (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/13712#pullrequestreview-1759748762
PR Review Comment: https://git.openjdk.org/jdk/pull/13712#discussion_r1412065454
PR Review Comment: https://git.openjdk.org/jdk/pull/13712#discussion_r1412066706
PR Review Comment: https://git.openjdk.org/jdk/pull/13712#discussion_r1412067763
PR Review Comment: https://git.openjdk.org/jdk/pull/13712#discussion_r1412069097
PR Review Comment: https://git.openjdk.org/jdk/pull/13712#discussion_r1412070654
PR Review Comment: https://git.openjdk.org/jdk/pull/13712#discussion_r1412072074
PR Review Comment: https://git.openjdk.org/jdk/pull/13712#discussion_r1412072305