Maven：编译OK，打包OK，编译+打包失败

Question

我有一个使用 Dagger2 并使用 Maven 构建的桌面 Java 项目。我不能按顺序运行compile 和package。这有效：

$ mvn clean
$ mvn compile

这很有效，生成了一个可以正常运行的可执行 jar：

$ mvn clean
$ mvn package

但这失败了：

$ mvn clean
$ mvn compile
$ mvn package

当package 到达使用 Dagger2 的模块时，它会输出：

[INFO] Changes detected - recompiling the module!

mvn -e package 的错误是：

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.3:compile (default-compile) on project weapon: Compilation failure -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.3:compile (default-compile) on project weapon: Compilation failure
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:213)
    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:84)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
    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:498)
    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:915)
    at org.apache.maven.plugin.compiler.CompilerMojo.execute(CompilerMojo.java:129)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
    ... 19 more

模块有这个依赖：

<dependency>
    <groupId>com.google.dagger</groupId>
    <artifactId>dagger</artifactId>
    <version>2.1</version>
    <scope>compile</scope>
</dependency>

该模块使用编译器插件版本 3.3，如下所示：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <dependencies>
        <dependency>
            <groupId>com.google.dagger</groupId>
            <artifactId>dagger-compiler</artifactId>
            <version>2.1</version>
        </dependency>
    </dependencies>
    <configuration>
        <source>1.7</source>
        <target>1.7</target>
        <forceJavacCompilerUse>true</forceJavacCompilerUse>
    </configuration>
</plugin>

这是唯一与 Dagger 相关的配置。为什么我不能在build 之后运行package？

可能相关：我认为不再需要forceJavacCompilerUse，但没有它，Dagger 似乎根本无法运行。我在生成的组件实现中遇到未知符号错误 (DaggerMyComponent)。

编辑：这是mvn -e package的完整输出，命令提示符到命令提示符：

kevin@aphrodite:~/Projects/IDEA/Dark Matter$ mvn -e package
[INFO] Error stacktraces are turned on.
[INFO] Scanning for projects...
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Build Order:
[INFO] 
[INFO] parent
[INFO] weapon
[INFO] scripts
[INFO] assembly
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building parent 2.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building weapon 2.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- maven-resources-plugin:2.3:resources (default-resources) @ weapon ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.3:compile (default-compile) @ weapon ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 8 source files to /home/kevin/Projects/IDEA/Dark Matter/weapon/target/classes
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] parent ............................................ SUCCESS [0.001s]
[INFO] weapon ............................................ FAILURE [1.641s]
[INFO] scripts ........................................... SKIPPED
[INFO] assembly .......................................... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.735s
[INFO] Finished at: Fri Mar 11 04:32:38 MST 2016
[INFO] Final Memory: 21M/173M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.3:compile (default-compile) on project weapon: Compilation failure -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.3:compile (default-compile) on project weapon: Compilation failure
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:213)
    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:84)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
    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:498)
    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:915)
    at org.apache.maven.plugin.compiler.CompilerMojo.execute(CompilerMojo.java:129)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
    ... 19 more
[ERROR] 
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[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/MojoFailureException
[ERROR] 
[ERROR] After correcting the problems, you can resume the build with the command
[ERROR]   mvn <goals> -rf :weapon
kevin@aphrodite:~/Projects/IDEA/Dark Matter$ 

编辑 2：我注意到当我在 clean 之后单独运行 package 时，它说它正在编译 6 个源。这就是项目中有多少手写类。当我在package 之前运行compile 时，后者说它正在编译8 个源。看起来当dagger-compiler 在一个干净的项目上运行时，它会默默地生成并编译它的源代码。然后package 看到新的源并尝试编译它们。谜团在于它失败的原因。连续运行两次compile 以同样的方式失败。

编辑 3： 我尝试了 this answer，将 dagger.internal.codegen.ComponentProcessor 指定为 -processor 参数。现在我第一次运行编译时，我看到它编译了 6 个文件和 8 个文件的两个通道：

[INFO] --- maven-compiler-plugin:3.3:compile (process-annotations) @ weapon ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 6 source files to /home/kevin/Projects/IDEA/Dark Matter/weapon/target/classes
[INFO] 
[INFO] --- maven-resources-plugin:2.3:resources (default-resources) @ weapon ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 1 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.3:compile (default-compile) @ weapon ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 8 source files to /home/kevin/Projects/IDEA/Dark Matter/weapon/target/classes

这是意料之中的，而且这个compile 成功了。但是如果我再次运行package 或compile，它会像以前一样失败。

Dagger 生成的源代码位于/target/generated-sources/annotations。我想我需要告诉 Maven 用那条路径做点什么，但我不知道是什么。 compile 在连续运行两次时检测到源更改是有道理的，尽管我不知道为什么会导致失败。也许我需要有条件地运行注释处理步骤，但我不知道该怎么做或条件应该是什么。

Answer 1

我设法重现了您的问题。

关键似乎是maven-compiler-plugin:3.3

当我使用maven-compiler-plugin:3.1 运行时，错误不会出现。