[RFR]8215622: Add dump to file support for jmap histo

[臧琳]

Dear All,
     Thanks again for the comments.
     one question from me is that "jmap -dump" must accept an argument indicates location of the heap dump file. if there is no such argument, it fails. (it is meaningless to output the binary directly to stdout/stderr for me.)
     so adding "jmap -dump" actually just output error message like "No dump file specified", rather than print the usage of JMap as implemented now.
     And this is also why there is no "-dump" or "-dump:" test in BasicJMapTest.java.

     Another option is to add default file generated at canonical path for -dump. then I can add the unit test.
     which one do you think is more reasonable?

     Moreover, one minor thing is that BasicJMapTest right now has test for "jmap -histo:" , not for "jmap -histo", so I think I need to add test for that. is this OK?

Cheers,
Lin
________________________________________
From: Joseph D. Darcy <joe.darcy at oracle.com>
Sent: Tuesday, February 12, 2019 6:22:59 AM
To: Hohensee, Paul; serguei.spitsyn at oracle.com; 臧琳; David Holmes; JC Beyler
Cc: serviceability-dev at openjdk.java.net
Subject: Re: [RFR]8215622: Add dump to file support for jmap histo

On 2/11/2019 2:20 PM, Hohensee, Paul wrote:
> The CSR was just closed, so we're stuck with doing another one later.

Before a changeset is pushed, its CSR can be amended (Withdraw or back
to draft, then refinalize after editing.)

HTH

-Joe