Compact Profiles for the Java Runtime (was: JFX build and deployment - squeaking wheel)

[Daniel Zwolenski]

So we should use this forum to discuss requirements for compact JREs for desktop JFX?


On 10/11/2012, at 10:34 AM, Bob Vandette <bob.vandette at oracle.com> wrote:

> On Nov 9, 2012, at 5:55 PM, Florian Brunner wrote:
> 
>> Hi Bob,
>> 
>> As I understand the profiles/ project Jigsaw in the context of JavaFX is it to makte it easier to port Java + JavaFX to other platforms especially by omitting AWT. So I understand that the following packages are omitted:
>> 
>> javax.awt.*
>> javax.swing.* (dependencies to AWT)
>> javax.imagio.* (dependencies to AWT)
>> 
>> But neither are any of the following packages mentioned:
>> 
>>    java.beans.*
>>    javax.accessibility
>>    javax.activation
>>    javax.activity
>>    javax.annotation
>>    javax.jws.*
>>    javax.print.*
>>    javax.sound.*
>>    org.omg.*
>> 
>> 
>> Now, I understand that the java.beans.PropertyEditor related classes cause an issue because of the dependency to AWT, but the JEP 161 states that some packages have to be split up anyway (which will probably cause issues with OSGi based library, though). And Java Beans patterns (and e.g. PropertyChangeListener) are used at many places in applications and frameworks.
> 
> We really want to avoid splitting packages because this will make it difficult to transition to Jigsaw in JDK9.
> 
> The PropertyChangeListener classes are problematic.  We currently have a small set of beans classes in compact1
> that we'd like to remove.  I've requested the fx team remove any dependency on these class in preparation for
> their possible removal.  They have a few JIRA's filed to track this change.
> 
> We have analyzed two different OSGi implementations and they don't appear to have any dependencies on these
> classes.
> 
> Can you provide us with a list of some concrete applications that you believe require Java Beans?  We could
> investigate the feasibility of pushing this package down to compact3 if there's enough demand and if it doesn't
> have any dependencies that we can't untangle.
> 
> 
>> 
>> I think there should be a profile (maybe Compact3?), which includes everything except AWT related classes to allow maximum reuse and portability of existing 3rd party libraries, which make the Java ecosystem so rich, so they can be used in JavaFX applications.
> 
> The compact3 profile is a very rich set of APIs.  The only large group of SE APIs that are not found in this profile are:  Desktop (AWT/SWING/Java2D), JAX-WS, and Corba.   
> 
> For embedded we felt that JAX-WS was too heavy weight and difficult to split up or subset.  We've been working under the assumption
> that embedded devices will probably continue to use the smaller kSoap or move to JAX-RS for lighter weight RestFul web services.
> 
>> 
>> And another question:
>> 
>> The JEP 161 states:
>> "If a package listed in a lower Profile in this table has subpackages then those subpackages are included in that Profile unless they are identified as members of some higher Profile. Thus the java.lang.reflect package, e.g., is in the Compact1 Profile, but java.lang.management is in the Compact3 Profile."
>> 
>> But the profile Compact1 states explicitly both java.util and java.util.logging.
>> 
>> What about the following packages?
>> 
>>    java.util.concurrent
>>    java.util.concurrent.atomic
>>    java.util.concurrent.locks
>>    java.util.jar
>>    java.util.regex
>>    java.util.spi
>>    java.util.zip
> 
> We were attempting to keep the contents of the JEP to the minimum.
> 
> These packages are covered by this statement "If a package listed in a lower Profile in this table has subpackages then those subpackages are included in that Profile ".  Since they aren't explicitly mentioned in higher profiles, they are in compact1.
> 
> Feel free to build your own set of linux 86 profiles where you can see exactly what we've proposed for each profile.
> 
> You could also grab a copy of this repo and look at the jdk/make/profile-rtjar-includes.txt file
> that lists the packages included in each compact profile level.
> 
> http://hg.openjdk.java.net/jdk8/profiles/jdk
> 
> Thanks for the input,
> Bob.
> 
>> 
>> I think it would be clearer if all subpackages were listed explicitly.
>> 
>> - Florian
>> 
>> Am Donnerstag, 8. November 2012, 16.11:31 schrieb Bob Vandette:
>>> There have been some questions on this list about Jigsaw, compact profiles,
>>> embedded, minimal VMs and the JRE customization tool called jrecreate.  
>>> Richard asked me to jump in to try to clear up any confusion.
>>> 
>>> Here goes ....
>>> 
>>> The Java Modularity Project (project Jigsaw) that was originally planned for
>>> JDK8 was deferred to JDK9. The Java Embedded team (I'm the lead) was
>>> expecting to use Jigsaw in order to provide smaller customizable Java
>>> runtimes for embedded devices.  Lacking this new functionality, we decided
>>> to propose a simpler alternate plan that would enhance the JDK8
>>> specification to allow the distribution of a small set of profiles that are
>>> subsets of the full Java runtime.   These are called Compact Profiles. We
>>> have proposed three compact profiles.  A talk and presentation that I gave
>>> at JavaOne describes these profiles.
>>> 
>>> https://oracleus.activeevents.com/connect/fileDownload/session/CDC887FAEAD8A
>>> BE54064406AC304AD59/CON4538_Vandette.pdf
>>> 
>>> The Java Enhancement Proposal (JEP) for this work is here:
>>> 
>>> http://openjdk.java.net/jeps/161
>>> 
>>> The openjdk repository that implements our current prototype is located
>>> here:
>>> 
>>> http://hg.openjdk.java.net/jdk8/profiles
>>> 
>>> The mailing list that discusses the profiles is
>>> build-infra-dev at openjdk.java.net since the creation of the new profiles is
>>> done using the new configure based JDK build system.
>>> 
>>> This repository allows you to do a build that generates the full JRE, JDK
>>> but in addition produces three additional image targets (compact1,
>>> compact2, and compact3).
>>> 
>>> In order to achieve the smallest Java runtime for embedded (our goal is
>>> around 10MB), we have applied changes to Hotspot that allow us to build a
>>> small VM (2-3MB) with reduced functionality.  The small VM (minimal) +
>>> compact1 profile goal we've set is around 10MB.  We're at 11MB today.
>>> 
>>> In addition to the profile bundles and the small VM, we have a reduced
>>> Embedded FX stack that we'll run on embedded devices such as the
>>> RaspberryPi.  This FX Embedded stack is a compatible FX implementation
>>> without media and webkit support.   The goal for this added stack is 6MB.
>>> 
>>> The jrecreate tool that some of you have asked about is not a java stripping
>>> tool.  It's main purpose is to assist the embedded developer in customizing
>>> Java runtimes.  It allows the developer to select which profile, VM,
>>> debugging options, compression, security and FX options.  It does not strip
>>> the full JRE to produce the compact profile. The jrecreate will be packaged
>>> with the three compact profile binaries.  It simply copies these profiles
>>> and applies some additional massaging based on the selected options.
>>> 
>>> We have already pushed the minimal VM changes to JDK8 hotspot and will be
>>> open sourcing the compact profile changes since they will be a standard
>>> feature of JDK8 (independent of embedded).  The current profile changes in
>>> our project repository are only functional for Linux x86.
>>> 
>>> We certainly recognize the value that small Java runtimes + reduced FX could
>>> have on Java applications published on Web App stores, but the current
>>> immediate plan is that the jrecreate tool is only going to be available
>>> with our embedded binary downloads since that's where it's needed most.  
>>> I've had some discussions with our Netbeans team to see what it will take
>>> to make Netbeans profile aware.  This might be a good way of taking
>>> advantage of profiles, reduced FX for producing smaller applications for
>>> distribution.
>>> 
>>> I hope this help,
>>> Bob.
>