Stephen, if we would never address problems that seem hard to fix at first sight, then the Maven core would never evolve and other system would take over some day. So a discussion like this one is essential for the future of this tool. There are too much things left open due to concerns like these (e. g. see the long lasting discussion about SNAPSHOTs being included in version ranges), so we should start solving them step by step instead of flinching due to virtual efforts. :-)
So let me chime in here and start a discussion by throwing a proposal in the ring: Introduction of the "Platform" interface in Maven 4! Possibly the best way to resolve the endorsed dependency problem mid-term would be to understand how it comes to the endorsed-ness: Obviously this is because someone in an official position (like the JCP) decides that something that was a "normal" dependency before now is "pre-packaged" with the official runtime package (like the JRE). In the end, that means, that Maven has to know about that decision to be able to deal with its effects. Looking it this way I have to contradict in part: * This is _not_ a Java-only problem, as potentially there could be endorsed libraries in other runtime systems, too, like .NET or Flash, or even Win32 (for example, I can vividly remember that "GDI+" first was a custom DLL that everyone had to ship with his own application EXE, but later it was part of the official Windows SDK, pre-packaged with the operating system; same with newer ODBC releases BTW). While I do not say that those named examples in fact do have an endorsement facility (obvisouly besides Win32 where I named two examples), it could be possible that _some_ other Maven-supported platform _will_ have such a facility now or in future. So as it is not a Java-only problem, it makes sense to have a _common_ solution. * It is _not_ a problem of scope, since scope is to be defined solely by the view of the using dependent project always. If the dependent project needs this library for test only, scope still is 'test' (e. g. a Win32 program might need a particular release of ODBC for an integration test, while at runtime it possibly might never use ODBC at all). The fact that a library was in user space in JRE 5 but is in system space in JRE 6 does not have any influence on this project's use, hence, of the scope. So there is no need for another scope. * Endorsed libraries are _not_ a problem of one particular dependent project, but an inherent decision of the platform itself (_every_ dependent project on this particular platform (JRE 6 in this example) suffer from the _same_ pain, as _the platform_ decides that this is endorsed, but neither the dependent project nor the dependency itself). So it is nothing to get configured in neither the dependent POM nor in the dependency's POM, but it is solely a third place that makes up the endorsed-ness: The POM of the "platform" (here: the POM of a hypthetical artifact that makes up what we know as "JRE 6"). Which simply does not exist in Maven 3 AFAIK. * As a result, it is _not_ a particular problem of the compiler, since _all_ compilers (jikes, javac, eclipse) need to support endorsed libraries. As all compilers might have different configuration switches, and selection of the particular compiler might be out of scope of the POM (i. e. defined in company pom for example), it simply is no sophisticated solution to provide particular javac options inside of each single dependent POM. * So as AFAIK Maven 3 does not yet know the concept of "Platform" modules, the solution obviously is to add this new concept to Maven 4: Strip the knowledge about the different platforms (hence, JREs) from the lots of plugins (like the compiler-plugin or the jar-plugin) into one single artifact which forms the "JRE 6 Platform" (including some general "Platform" interface common not only for the JREs but for all kinds of "Platforms" like .NET and Flash etc.). Using this interface, Maven could resolve the question "Is this dependency to be put in the root classpath, or in the user classpath?" automatically. Maven simply needs to ask the platform (using the new interface) what the right classpath is, and the platform would answer with either 'User' or 'System' (interface-defined enum constants for example). So the JRE 5 might answer with 'User' while JRE 6 might answer with 'System' for the same dependency! No need for _any_ configuration in the POM! No need for _any_ POM schema change! Maven could simply set up the root classpath fully automatically that way! Just like one day Eclipse learned the difference between "JRE" and the general term "Platform", Maven 4 has to learn this concept, too. Maybe I should file a RFE for this? Regards Markus > -----Original Message----- > From: Stephen Connolly [mailto:stephen.alan.conno...@gmail.com] > Sent: Samstag, 22. September 2012 00:09 > To: Maven Users List > Subject: Re: How to put a dependency in the classpath BEFORE jre.jar? > > 1. Maven is not just about java (though very java focused I admit) > endorsed does not make sense outside of java 2. Whether a dependency > needs to be endorsed or not depends on the jvm version it targets... A > dep can be fine until it gets added to the jvm spec. > 3. It should probably more correctly be <scope>endorsed</scope> 4. > Where would you package an endorsed dependency within a .war or .ear > file? > > And don't get me started on the fact that to change this requires > changing the Pom format (which potentially could break ivy, gradle, > leinengen, sbt, > etc) > > Not an easy problem to solve, but I feel your pain > > On Friday, 21 September 2012, Markus KARG wrote: > > > Thank you for pointing me to this excellent blog entry, but in fact I > > wonder why such a great tool like Maven doesn't have built-in support > > for endorsed dependencies? I mean, in the end a different compiler > > might break the solution, so it would be a good idea if a dependency > > could simply marked as <endorsed>true</endorsed>. > > > > > -----Original Message----- > > > From: Claves Do Amaral > > > [mailto:claves.doama...@igmarkets.com<javascript:;> > > ] > > > Sent: Donnerstag, 20. September 2012 10:30 > > > To: Maven Users List > > > Subject: RE: How to put a dependency in the classpath BEFORE > jre.jar? > > > > > > If I understand the problem well, this is equivalent to provide > > > endorsed libraries at runtime. > > > I have found this resource, that looks a bit dated, but it may > work. > > > Not sure if Maven 3 offers a better solution > > > > > > http://www.mindbug.org/2009/02/adding-endorsements-to-mavens- > > > plugins.html > > > > > > Claves > > > > > > -----Original Message----- > > > From: Markus Karg [mailto:k...@quipsy.de <javascript:;>] > > > Sent: 20 September 2012 09:22 > > > To: users@maven.apache.org <javascript:;> > > > Subject: How to put a dependency in the classpath BEFORE jre.jar? > > > > > > I have a dependency on javaee.jar, which provides newer versions > for > > > classes found in JRE's jre.jar (particularly the @Resource > annotation). > > > But javaee.jar is always appended to the classpath, while to be > able > > > to load the newer version, I need to PREFIX it before jre.jar > > > instead. 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