[
https://issues.apache.org/jira/browse/MCOMPILER-433?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Guillaume Nodet closed MCOMPILER-433.
-------------------------------------
Assignee: Guillaume Nodet (was: Olivier Lamy)
Resolution: Fixed
> mvn clean compile test compiles the source files twice
> ------------------------------------------------------
>
> Key: MCOMPILER-433
> URL: https://issues.apache.org/jira/browse/MCOMPILER-433
> Project: Maven Compiler Plugin
> Issue Type: Bug
> Affects Versions: 3.8.1
> Reporter: Dan Berindei
> Assignee: Guillaume Nodet
> Priority: Major
> Fix For: 3.11.0
>
>
> When one invokes {{mvn clean compile test}}, the {{default-compile}}
> execution runs twice.
> This is because
> {{org.apache.maven.lifecycle.internal.DefaultLifecycleExecutionPlanCalculator#calculateMojoExecutions()}}
> (which hasn't changed in 6 years) collects the list of mojo executions in a
> list, and for each phase on the command-line it adds the mojo executions for
> that phase and its dependencies, even if some executions already exist in the
> list. E.g.
> {noformat}
> mojoExecutions = {java.util.ArrayList} size = 8
> 0 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-clean-plugin:2.5:clean {execution:
> default-clean}"
> 1 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-resources-plugin:2.6:resources {execution:
> default-resources}"
> 2 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile {execution:
> default-compile}"
> 3 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-resources-plugin:2.6:resources {execution:
> default-resources}"
> 4 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile {execution:
> default-compile}"
> 5 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-resources-plugin:2.6:testResources
> {execution: default-testResources}"
> 6 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-compiler-plugin:3.8.1:testCompile {execution:
> default-testCompile}"
> 7 = {org.apache.maven.plugin.MojoExecution}
> "org.apache.maven.plugins:maven-surefire-plugin:2.12.4:test {execution:
> default-test}"
> {noformat}
>
> The second execution of {{maven-compiler-plugin}} version 3.8.0 used to check
> that the sources haven't changed and do nothing. But that check was wrong,
> because it didn't check any class files, and MCOMPILER-349 replaced it with
> another check that is also wrong, because it
> ({{org.apache.maven.plugin.compiler.AbstractCompilerMojo#isDependencyChanged()}})
> checks for changes since the start of the build in all the classes on the
> module's classpath, including {{target/classes}}.
> This means the second execution of {{maven-compiler-plugin}} verison 3.8.1
> deletes all the {{.class}} files from {{target/classes}}. It does not delete
> the files generated by annotation processors in
> {{target/generated-sources/annotations}}, but it also doesn't add them to the
> Javac sources parameter because
> {{org.apache.maven.plugin.compiler.AbstractCompilerMojo#getCompileSources()}}
> ignores the generated sources directory:
> {noformat}
> compileSourceRoots = {java.util.ArrayList} size = 3
> 0 = "/home/dan/Work/maven-compiler-test/src/main/java"
> 1 = "/home/dan/Work/maven-compiler-test/target/generated-sources/annotations"
> 2 = "/home/dan/Work/maven-compiler-test/target/generated-sources/annotations"
> {noformat}
> {noformat}
> sources = {java.util.HashSet} size = 2
> 0 = {java.io.File}
> "/home/dan/Work/maven-compiler-test/src/main/java/ProtoStreamContextInitializer.java"
> 1 = {java.io.File} "/home/dan/Work/maven-compiler-test/src/main/java/A.java"
> {noformat}
>
> We have an annotation processor that tries to be smart and doesn't overwrite
> its generated Java source files if they already exists and they have the
> correct checksum. But because the generated file isn't written, it is not
> added to Javac's sources, and Javac does not compile it to a {{.class}} file.
> I haven't tested it, but I believe the same problem appears if the source
> files were generated e.g. by another Maven plugin or by an Ant script in the
> {{generate-sources}} phase.
>
> I believe the maven-core behaviour won't change any time soon (and in fact
> some users may depend on the duplicate executions). Instead
> {{org.apache.maven.plugin.compiler.AbstractCompilerMojo#isDependencyChanged()}}
> needs to be fixed to avoid recompilation when runs the second time.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
