[Engine-devel] java 1.6 compatibility no more?

[Allon Mureinik]

----- Original Message -----
> From: "Vojtech Szocs" <vszocs at redhat.com>
> To: "Juan Hernandez" <jhernand at redhat.com>
> Cc: engine-devel at ovirt.org
> Sent: Thursday, July 19, 2012 2:31:40 PM
> Subject: Re: [Engine-devel] java 1.6 compatibility no more?
> 
> > Don't we need that (the source part) to avoid Java 7 syntax in GWT
> > code?
> 
> That's a very good point.
> 
> In general, GWT compiler supports Java 5 syntax (note that there are
> no language changes between Java 5 and 6). 
This may be nitpicking, but there is a difference:
Java 6 allows the @Override annotation for implementing interfaces, 
while Java 5 restricts it to actual overrides.
This is widely used throughout our code, at least in the backend side.

> For this reason, our
> frontend code should be compliant with Java 5. If someone uses new
> Java 7 language features in frontend code, GWT compiler will throw
> an error and the build will fail.
> 
> So the 'Java 5 only' limitation applies to frontend code and any
> other code (e.g. shared modules) that is directly referenced by
> frontend code. This shouldn't affect the backend, however.
> 
> We could do something like this:
> 
> - let oVirt root POM declare source and target compliance to Java 7
> - let frontend modules POM (frontend/webadmin/modules/pom.xml)
> declare source compliance to Java 5 (or 6)
> 
> (note that target compliance can be left to Java 7 since frontend
> compilation results in JavaScript code)
> 
> What do you think?
> 
> Vojtech
> 
> 
> ----- Original Message -----
> From: "Juan Hernandez" <jhernand at redhat.com>
> To: "Vojtech Szocs" <vszocs at redhat.com>
> Cc: "Yair Zaslavsky" <yzaslavs at redhat.com>, engine-devel at ovirt.org
> Sent: Thursday, July 19, 2012 11:01:00 AM
> Subject: Re: [Engine-devel] java 1.6 compatibility no more?
> 
> On 07/19/2012 10:09 AM, Vojtech Szocs wrote:
> >> As I previously emailed - JDK7 already fixed a known issue with
> >> ldap and
> >> DNS ,and made one of my patches at gerrit redundant.
> >> Why not enjoy the bug fixes?
> > 
> > I agree, but in that case, why not switch to '1.7' Java
> > source/target compliance for oVirt Maven build as well?
> > 
> > If JDK6 cannot be used for building oVirt (because of missing Java
> > 7 APIs, because of LDAP/DNS issues in JDK6, etc.), we should also
> > update our Maven POM files. Currently, when I import oVirt
> > projects into Eclipse (using Eclipse Maven plugin), I'm getting
> > compile errors on 'bll' project. This is because our Maven POM
> > files declare '1.6' Java source/target compliance.
> > 
> > Juan - you are right, but for me, it sounds quite strange to have
> > '1.6' Java source/target compliance for Maven build, and use JDK7
> > to do the build.
> 
> Don't we need that (the source part) to avoid Java 7 syntax in GWT
> code?
> 
> > ----- Original Message -----
> > From: "Yair Zaslavsky" <yzaslavs at redhat.com>
> > To: engine-devel at ovirt.org
> > Sent: Thursday, July 19, 2012 7:59:45 AM
> > Subject: Re: [Engine-devel] java 1.6 compatibility no more?
> > 
> > On 07/18/2012 08:21 PM, Juan Hernandez wrote:
> >> On 07/18/2012 06:33 PM, Vojtech Szocs wrote:
> >>> In fact, for both backend and frontend, Maven effective POM
> >>> contains:
> >>>
> >>> <artifactId>maven-compiler-plugin</artifactId>
> >>> <configuration>
> >>>   <source>1.6</source>
> >>>   <target>1.6</target>
> >>> </configuration>
> >>>
> >>> Therefore, according to Maven POM files, oVirt should be
> >>> build-able using Java 6, but it's not. (?)
> >>
> >> These maven settings just tell the java compiler to accept Java 6
> >> syntax
> >> only and to generate a Java 6 compatible .class file format, but
> >> they
> >> don't restrict the set of APIs that can be used.
> >>
> >>> The problem is in backend/manager/modules/bll:
> >>> StorageDomainCommandBase class uses new Java 7 Long.compare()
> >>> static method.
> >>>
> >>> I think we should decide if we want to be compliant with Java 7,
> >>> or submit a patch that uses Java 6 API (Long.compareTo instance
> >>> method).
> >>>
> >>> Vojtech
> > 
> > As I previously emailed - JDK7 already fixed a known issue with
> > ldap and
> > DNS ,and made one of my patches at gerrit redundant.
> > Why not enjoy the bug fixes?
> > 
> >>>
> >>>
> >>> ----- Original Message -----
> >>> From: "Laszlo Hornyak" <lhornyak at redhat.com>
> >>> To: "engine-devel" <engine-devel at ovirt.org>
> >>> Cc: "Vojtech Szocs" <vszocs at redhat.com>
> >>> Sent: Wednesday, July 18, 2012 5:43:34 PM
> >>> Subject: java 1.6 compatibility no more?
> >>>
> >>> Hi,
> >>>
> >>> It may be a historic moment, but for a few hours oVirt engine is
> >>> no longer building on java 1.6.
> >>> Is this intentional?
> >>>
> >>> Laszlo
> >>> _______________________________________________
> >>> Engine-devel mailing list
> >>> Engine-devel at ovirt.org
> >>> http://lists.ovirt.org/mailman/listinfo/engine-devel
> >>>
> >>
> >>
> > 
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> > 
> 
> 
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