Mailing-List: contact dev-help@commons.apache.org; run by ezmlm
Precedence: bulk
Reply-To: "Commons Developers List" <dev@commons.apache.org>
Received-SPF: pass (athena.apache.org: local policy)
Date: Thu, 14 Jun 2012 23:24:07 +0200
From: Gilles Sadowski <gilles@harfang.homelinux.org>
To: dev@commons.apache.org
Subject: Re: [Math] How to select a specific JDK ?
Message-ID: <20120614212407.GE10938@dusk.harfang.homelinux.org>
Mail-Followup-To: dev@commons.apache.org
References: <20120613115648.GV32074@dusk.harfang.homelinux.org>
 <CAOfDJ6tJGpBWatJo1F-AUDQnCMF+t52dPZDvTh4wVM8J_BOD7w@mail.gmail.com>
 <20120613124358.GX32074@dusk.harfang.homelinux.org>
 <CAOfDJ6vQ8o_0e0DN_PEsV5pseZTb976WL7c25FbU0acEAA2CJQ@mail.gmail.com>
 <20120613144734.GY32074@dusk.harfang.homelinux.org>
 <jragsp$ip$1@dough.gmane.org>
 <20120613173032.GE32074@dusk.harfang.homelinux.org>
 <CAOGo0VbsQtqWbFHU87E-wweRLmQS9tqDW+WotoEUi9sjwrAkVw@mail.gmail.com>
 <20120614011502.GC10938@dusk.harfang.homelinux.org>
 <CAOGo0VYHrBbTe-xU2dsuU0cqEDHnR0=G47uRuxsQ0EiP92UNJw@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: 
 <CAOGo0VYHrBbTe-xU2dsuU0cqEDHnR0=G47uRuxsQ0EiP92UNJw@mail.gmail.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
X-DCC-scarlet.be-Metrics: hel 20001; Body=1 Fuz1=1 Fuz2=1
X-Virus-Scanned: clamav-milter 0.97.1-exp at hel
X-Virus-Status: Clean
X-Virus-Checked: Checked by ClamAV on apache.org

On Thu, Jun 14, 2012 at 05:31:23PM +0100, sebb wrote:
> On 14 June 2012 02:15, Gilles Sadowski <gilles@harfang.homelinux.org> wrote:
> > Hello.
> >
> >> > [...]
> >
> > The following:
> >
> >> >> > I should be able to do all combinations, i.e.:
> >> >> > �1. Compile with javac 1.6 and run with java 1.6
> >> >> > �2. Compile with javac 1.7 and run with java 1.7
> >
> > is achieved by those respective commands:
> >
> > �$ JAVA_1_6_HOME=/usr/lib/jvm/java-6-sun mvn -X -Pjava-1.6 clean test
> > �$ JAVA_1_7_HOME=/usr/lib/jvm/java-7-openjdk-amd64 mvn -X -Pjava-1.7 clean test
> >
> > IIUC:
> > �JAVA_x_y_HOME is used to locate the "javac" executable
> 
> Sort of.
> 
> > �-Pjava-x.y selects the language level
> 
> -P selects the profile, which uses the relevant JAVA_1_n_HOME variable
> to locate the relevant Java installation.
> These variable were introduced specifically to support the java-x.y profiles.

The profile also sets "commons.compiler.compilerVersion", and I inferred
that this would define which version of the language is accepted by the
compiler. Is that correct?

> 
> > �JAVA_HOME has no effect
> >
> > This, however,
> >
> >> >> > �3. Compile with javac 1.6 and run with java 1.7
> >
> > is not so easy. �To run the tests with 1.7, one needs
> >
> > �$ JAVA_1_6_HOME=/usr/lib/jvm/java-6-sun mvn -Dcommons.surefire.java=/usr/lib/jvm/java-7-openjdk-amd64/bin/java -X -Pjava-1.6 clean test
> 
> >> > [...]
> >
> > Much to my surprise, this
> >
> > �$ JAVA_1_7_HOME=/usr/lib/jvm/java-7-openjdk-amd64 mvn -Dcommons.surefire.java=/usr/lib/jvm/java-6-sun/bin/java -X -Pjava-1.7 clean test
> >
> > (i.e. using java 1.6 to run classes compiled with javac 1.7) also works! Is
> > that expected? [I thought I'd get the "incompatible major.minor version"
> > exception.]
> 
> Unless you are using an updated version of the parent pom, the profile
> java-1.7 does not exist - this should report an error, but it might
> get lost in the -X output -  so the compilation will use your default
> java compiler.

Excerpt (with line numbers) of "commons-parent-24.pom":
---
    858     <profile>
    859       <id>java-1.7</id>
    860       <properties>
    861         <commons.compiler.fork>true</commons.compiler.fork>
    862           <commons.compiler.compilerVersion>1.7</commons.compiler.compilerVersion>
    863           <commons.compiler.javac>${JAVA_1_7_HOME}/bin/javac</commons.compiler.javac>
    864          <commons.surefire.java>${JAVA_1_7_HOME}/bin/java</commons.surefire.java>
    865       </properties>
    866     </profile>
---


Regards,
Gilles

---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscribe@commons.apache.org
For additional commands, e-mail: dev-help@commons.apache.org