RFR: JDK-8200132: Remove jre images and bundles

[Bob Vandette]

> On Jun 4, 2018, at 4:32 PM, Jonathan Gibbons <jonathan.gibbons at oracle.com> wrote:
> 
> 
> 
> On 06/02/2018 12:20 AM, Alan Bateman wrote:
>> On 02/06/2018 08:05, Aleksey Shipilev wrote:
>>> :
>>> Unfortunately, in the age of containers, distribution size matters. It makes the whole sense to ship
>>> JRE in Docker containers to provide the execution environment for the upper layers. Remember, hardly
>>> any application is fully modularized and/or uses jlink/jimage way of distribution.
>>> 
>>> Also, products that ship with their own OpenJDK distribution (e.g. JetBrains IDEs) do ship with
>>> jres, which cuts down their distribution sizes.
>>> 
>>> Cost savings for having JRE only are significant, as can be observed with current bundles:
>>> 
>>>  178M Jun  2 08:53 jdk-11-internal+0_linux-x64_bin.tar.gz
>>>   38M Jun  2 08:53 jre-11-internal+0_linux-x64_bin.tar.gz
>>> 
>>> Therefore, I believe removing jre is too disruptive, at least for 11, at least until we see that the
>>> whole jlink/jimage thing really works out in the wider Java ecosystem and JREs are really abandoned.
>> I don't disagree with the significance of what has been proposed here. However, just to point out that creating what used to know as the JRE is one `jlink` command. There is no requirement for the application or libraries using that run-time be developed as modules. Also incorporate generating of JDK run-time images into the build when working with containers is very useful as you get fine control on which modules to include.
>> 
>> -Alan
>> 
> 
> If it is that easy to generate a JRE image, why not provide a target to create such an image, that invokes that one command?  The target need not be part of the default build, but would be available for those that want to build it.

I could live with a jlink option to create a JRE.  The problem is that the list of modules required to produce a
compatible JRE is not documented anywhere.  I tried fishing the list out of the build makefile but it’s not trivial.  I ended
up running “jimage list module | grep Module: on a JDK 10 JRE to get the list.

Bob.


> 
> -- Jon