Re: feedback on Maven 4.0.0 RC5

Thanks, great feedback!

CC to dev@

- Ben


On 2 April 2026 15:08:37 CEST, Olivier Bourgain <olivierbourgain02@gmail=
=2Ecom> wrote:
>Hello,
>
>After meeting Herv=C3=A9 at an event, I tried using Maven 4 on $COMPANY's
>projects=2E
>I have a script to build about 140 projects, including libraries and
>applications and two Maven plugins=2E
>I encountered one bug, and I think I can make a few suggestions to improv=
e
>the UX=2E
>The mail is quite long and about several topics, I can break it to
>different topics if you prefer=2E
>
>1- the Bug
>Summary: can't combine ! and ? for profiles=2E
>
>Related to https://issues=2Eapache=2Eorg/jira/browse/MNG-7051
>
>Detailed description:
>My build script sets a bunch of profiles and applies them blindly to all
>projects=2E
>The profiles have various purposes, like building a front app and embed i=
t
>in an artifact, run code gen plugins etc=2E
>With Maven 3, for projects that don't have this profile, I just get a
>warning=2E Maven 4 is more strict and fails=2E I can mark the profile as
>optional with -P?xxx  and that's fine=2E
>The issue arises with profiles that are activeByDefault=2E I can not comb=
ine
>? and ! to ask Maven 4 to disable the profile if it exists, and ignore it
>if it doesn't exist=2E
>
>2- UX improvements
>a- When a profile doesn't exist, I get the following error:
>
>[ERROR] The requested profiles [foo] could not be activated or deactivate=
d
>because they do not exist=2E -> [Help 1]
>[ERROR]
>[ERROR] To see the full stack trace of the errors, re-run Maven with the
>'-e' switch
>[ERROR] Re-run Maven using the '-X' switch to enable verbose output
>[ERROR]
>[ERROR] For more information about the errors and possible solutions,
>please read the following articles:
>[ERROR] [Help 1]
>http://cwiki=2Eapache=2Eorg/confluence/display/MAVEN/MissingProfilesExcep=
tion
>
>- the link is dead
>- the message could be improved to make the existence of '?' more
>discoverable=2E
>e=2Eg:
>
>[ERROR] The requested profiles [foo] could not be activated or deactivate=
d
>because they do not exist=2E If this is expected, mark the profile as
>optional with '?'
>
>
>b- the following message is not actionable
>
>[INFO] Artifact com=2Esun=2Eactivation:all:pom:1=2E2=2E2 is present in th=
e local
>repository, but cached from a remote repository ID that is unavailable in
>current build context, verifying that is downloadable from [central (
>https://repo=2Emaven=2Eapache=2Eorg/maven2, default, releases)]
>
>Maybe more information about how this situation can arise, and the issue =
it
>causes=2E I have no precise suggestion here=2E
>
>
>c- this should be DEBUG
>I get what it is about, but as I user this is not a useful information
>about my build:
>
>[INFO] Loaded 22245 auto-discovered prefixes for remote repository centra=
l
>(prefixes-central=2Etxt)
>
>d- Missing an explanation of the why
>Could be inline if short enough or a link to doc
>
>[WARNING] Unable to find the root directory=2E Create a =2Emvn directory =
in the
>root directory or add the root=3D"true" attribute on the root project's m=
odel
>to identify it=2E
>
>e- error reporting contains a lot of duplicate information between root a=
nd
>modules=2E Maybe they can be grouped by category=2E
>E=2Eg=2E
>[WARNING] 3 problems were encountered while building the effective model
>for 'com=2Eacme:the-module:jar:latest-SNAPSHOT' (use -e to see details)
>[WARNING] Ignored POM import for:
>commons-logging:commons-logging:jar:1=2E3=2E5@compile as already imported
>commons-logging:commons-logging:jar:99-empty@compile=2E Add the conflicti=
ng
>managed dependency directly to the dependencyManagement section of the PO=
M=2E
>[WARNING] Ignored POM import for:
>org=2Eassertj:assertj-core:jar:3=2E27=2E6@compile as already imported
>org=2Eassertj:assertj-core:jar:3=2E27=2E7@compile=2E Add the conflicting =
managed
>dependency directly to the dependencyManagement section of the POM=2E
>[WARNING] Ignored POM import for:
>org=2Eeclipse=2Eangus:jakarta=2Email:jar:2=2E0=2E3@compile as already imp=
orted
>org=2Eeclipse=2Eangus:jakarta=2Email:jar:2=2E0=2E5@compile=2E Add the con=
flicting
>managed dependency directly to the dependencyManagement section of the PO=
M=2E
>[WARNING]
>[WARNING] 3 problems were encountered while building the effective model
>for 'com=2Eacme:the-root:pom:latest-SNAPSHOT' (use -e to see details)
>[WARNING] Ignored POM import for:
>commons-logging:commons-logging:jar:1=2E3=2E5@compile as already imported
>commons-logging:commons-logging:jar:99-empty@compile=2E Add the conflicti=
ng
>managed dependency directly to the dependencyManagement section of the PO=
M=2E
>[WARNING] Ignored POM import for:
>org=2Eassertj:assertj-core:jar:3=2E27=2E6@compile as already imported
>org=2Eassertj:assertj-core:jar:3=2E27=2E7@compile=2E Add the conflicting =
managed
>dependency directly to the dependencyManagement section of the POM=2E
>[WARNING] Ignored POM import for:
>org=2Eeclipse=2Eangus:jakarta=2Email:jar:2=2E0=2E3@compile as already imp=
orted
>org=2Eeclipse=2Eangus:jakarta=2Email:jar:2=2E0=2E5@compile=2E Add the con=
flicting
>managed dependency directly to the dependencyManagement section of the PO=
M=2E
>[WARNING]
>[WARNING] Total model problems reported: 6
>
>Deduplication could help readability, in particular as in my case the
>problem in 'the-module' are inherited from 'the-root' and should be fixed
>there=2E
>E=2Eg=2E we could have something like
>[WARNING] 3 problems were encountered while building the effective model
>for 'com=2Eacme:the-root:pom:latest-SNAPSHOT' (use -e to see details)
>[WARNING] Also impacts: ['com=2Eacme:the-module:jar:latest-SNAPSHOT']
>[WARNING] Ignored POM import for:
>commons-logging:commons-logging:jar:1=2E3=2E5@compile as already imported
>commons-logging:commons-logging:jar:99-empty@compile=2E Add the conflicti=
ng
>managed dependency directly to the dependencyManagement section of the PO=
M=2E
>[WARNING] Ignored POM import for:
>org=2Eassertj:assertj-core:jar:3=2E27=2E6@compile as already imported
>org=2Eassertj:assertj-core:jar:3=2E27=2E7@compile=2E Add the conflicting =
managed
>dependency directly to the dependencyManagement section of the POM=2E
>[WARNING] Ignored POM import for:
>org=2Eeclipse=2Eangus:jakarta=2Email:jar:2=2E0=2E3@compile as already imp=
orted
>org=2Eeclipse=2Eangus:jakarta=2Email:jar:2=2E0=2E5@compile=2E Add the con=
flicting
>managed dependency directly to the dependencyManagement section of the PO=
M=2E
>[WARNING]
>[WARNING] Total model problems reported: 3
>
>Thanks=2E