8373097: Save command should create missing parent directories

[sormuras]

Please review this change enhancing the /save <file> command in JShell to create missing parent directories.

Prior to this change, when the argument of a /save command starts with a list of directory names, of which at least one does not exist, the command fails with an exception reading:

/save some/path/Snippet.java
| File 'some/path/Snippet.java' for '/save' threw exception: java.nio.file.NoSuchFileException: some\path\Snippet.java

Any exception happening during the creation of missing parent directories (using Files.createDirectories API) is caught and transformed into file-related error message.

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Progress

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Issue

• JDK-8373097: Save command should create missing parent directories (Enhancement - P4)

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[bridgekeeper]

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[openjdk]

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[openjdk]

@sormuras Unknown command save - for a list of valid commands use /help.

[mlbridge]

Webrevs

• 00: Full (668701df)