为什么Maven 3.3不包含'javax.inject'但是Maven 3.2呢？

Question

My Maven build fails when using Maven 3.3.1 but is successful with Maven 3.2.2.

So far I have run /path/to/3.3.1/mvn clean compile -X and compared the output to the one produced by /path/to/3.2.2/mvn clean compile -X .

There was exactly one difference in the following block inside the maven-compiler-plugin / default-compile phase:

[DEBUG] Populating class realm plugin>org.apache.maven.plugins:maven-compiler-plugin:3.2
[DEBUG]   Included: org.apache.maven.plugins:maven-compiler-plugin:jar:3.2
[DEBUG]   Included: com.google.dagger:dagger-compiler:jar:2.0
[DEBUG]   Included: com.google.dagger:dagger:jar:2.0
[DEBUG]   Included: com.google.dagger:dagger-producers:jar:2.0-beta
[DEBUG]   Included: com.google.guava:guava:jar:18.0
...

Difference: While Maven 3.2.2 printed [DEBUG] Included: javax.inject:javax.inject:jar:1 , it is missing for Maven 3.3.1.

I don't know if this helps, but this is my effective build plugin:

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.2</version> <!-- 3.3 respectively -->
    <dependencies>
        <dependency>
            <groupId>com.google.dagger</groupId>
            <artifactId>dagger-compiler</artifactId>
            <version>2.0</version>
        </dependency>
    </dependencies>
    <configuration>
        <source>1.8</source>
        <target>1.8</target>
        <!-- workaround for http://jira.codehaus.org/browse/MCOMPILER-202 -->
        <forceJavacCompilerUse>true</forceJavacCompilerUse>
    </configuration>
</plugin>

What I don't understand: What exactly does the "Populating class realm plugin" do? Why is a jar missing, even though it has been identified as a dependency by both maven versions?

Edit: Build fails with this exception:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.2:compile (default-compile) on project ui: Compilation failure -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.2:compile (default-compile) on project ui: Compilation failure
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:212)
    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.compiler.CompilationFailureException: Compilation failure
    at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:913)
    at org.apache.maven.plugin.compiler.CompilerMojo.execute(CompilerMojo.java:129)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
    ... 20 more

A minimal example project is available on GitHub . The full output of the failing command is available here .

Answer 1

The problem is not with the version of maven-compiler-plugin.
When you use the option forceJavacCompilerUse it would basically use javax.tool API implementation within your JDK.
Since you are using dagger-compiler , which is intern dependent on javax.inject , it should get pulled.

You can try adding [provided] scope for your dagger-compiler plugin dependency, this way you would be locking all the transitive dependencies.

Also make sure that you have added dagger dependency in your runtime dependencies.

Please provide the some more details of exception-stack-trace and other related areas of your pom that would help visitors to narrow-down the problem and guide you quick!