Failed to execute goal org.apache.maven.plugins:maven-dependency-plugin:2.10

Question

I have this error when attempting to install the maven project:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-dependency-plugin:2.10:analyze-only (analyze-only) on project functional-tests: Dependency problems found -> [Help 1]

It appears right after the integration tests, during the verify phase. I can hardly guess where to look as not much other information is provided by the logs. I tried to run maven with -X argument to have a deeper look but that's the only error that appears. The last thing I see before the error appears in the detailed log is this WARNING below (that I doubt has anything to do with the error):

[WARNING] Used undeclared dependencies found:
[WARNING]    javax.activation:activation:jar:1.1:test
[WARNING] Unused declared dependencies found:
[WARNING]    org.slf4j:slf4j-log4j12:jar:1.7.6:compile
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 27.090 s
[INFO] Finished at: 2017-06-28T10:58:54+08:00
[INFO] Final Memory: 60M/1042M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-dependency-plugin:2.10:analyze-only (analyze-only) on project functional-tests: Dependency problems found -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-dependency-plugin:2.10:analyze-only (analyze-only) on project functional-tests: Dependency problems found
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-dependency-plugin:2.10:analyze-only (analyze-only) on project functional-tests: Dependency problems found
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:216)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:862)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:286)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:197)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
Caused by: org.apache.maven.plugin.MojoExecutionException: Dependency problems found
    at org.apache.maven.plugin.dependency.analyze.AbstractAnalyzeMojo.execute(AbstractAnalyzeMojo.java:260)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
    ... 20 more
[ERROR] 
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

What could be causing this issue?

UPDATE: I have resolved the issues that caused the warnings above and it did help removing the error. Now I only wonder why having used undeclared dependencies or declared unused dependencies are causing the whole build to fail?

UPDATE2: Changing the slf4j scope to runtime also solved the problem.

Answer 1

Apparently the used undeclared dependencies warning was the culprit of my problem. After adding the dependency explicitly to the pom file, the issue was resolved.