I'm seeing this in both 2.0.2 and 2.0.3, but not in 1.0.2. I specify a
version for a dependency in the parent pom.xml. As the build goes on, one
or more dependencies will be processed in the modules that have earlier
versions, and those earlier versions override the version I specified.
For example:
<dependency>
<groupId>commons-collections</groupId>
<artifactId>commons-collections</artifactId>
<version>3.1</version>
</dependency>
Then from the log:
[DEBUG] struts:struts:jar:1.2.4:compile (selected for compile)
[DEBUG] oro:oro:jar:2.0.7:compile (selected for compile)
[DEBUG] commons-logging:commons-logging:jar:1.0.4:compile (selected for
compile)
[DEBUG] commons-fileupload:commons-fileupload:jar:1.0:compile (selected
for compile)
[DEBUG] commons-collections:commons-collections:jar:2.1:compile(selected
for compile)
[DEBUG] commons-beanutils:commons-beanutils:jar:1.6.1:compile (selected
for compile)
[DEBUG] commons-logging:commons-logging:jar:1.0:compile (removed -
nearer found: 1.0.4)
[DEBUG] commons-collections:commons-collections:jar:2.0:compile(removed
- nearer found:
2.1)
[DEBUG] commons-digester:commons-digester:jar:1.5:compile (selected for
compile)
[DEBUG] commons-beanutils:commons-beanutils:jar:1.6:compile (removed -
nearer found: 1.6.1)
And what is in the WAR file is:
[DEBUG] adding entry WEB-INF/lib/commons-collections-2.1.jar
This is contrary to the documentation on the web site:
http://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html
Which says:
*Dependency mediation* - this determines what version of a dependency will
be used when multiple versions of an artifact are encountered. Currently,
Maven 2.0 only supports using the "nearest definition" - so you can always
guarantee a version by declaring it explicitly in your project's POM.
I take this to mean that the POM is based on the parent pom.xml in a
multiproject build, and the modules should inherit the version setting from
the parent. So I haven't tried to specify the version again in a child
pom.xml.
I came across this while converting a project from M1 to M2. The M1 WAR
file contains version 3.1, as expected.
Am I missing something?
Ray
