[MCOMPILER-538] Do not add target/generated-sources/annotations to the source roots

[mensinda]

Fix for MCOMPILER-538.

The generatedSourcesPath will still be added to the maven project paths.

---

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[jorsol]

I have been checking the javac options, and testing with this change, it does seem that we don't need to specify the generated-sources/annotations in the -sourcepath argument, it should be more than enough to specify it on the -s option.

[Nthalk]

All my projects that test upgrades to 3.12.0 fail because of this line, looking forward to when it's removed!

[slawekjaranowski]

All my projects that test upgrades to 3.12.0 fail because of this line, looking forward to when it's removed!

@Nthalk We need more details. There is a version 3.12.1 under vote, will be available in a few day. Please comments in JIRA

[Nthalk]

All my projects that test upgrades to 3.12.0 fail because of this line, looking forward to when it's removed!

@Nthalk We need more details. There is a version 3.12.1 under vote, will be available in a few day. Please comments in JIRA

I'm using renovate for auto dependency upgrades on multiple projects, the simplest doesn't use any annotation processing and yields this error on mvn clean install:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.12.0:testCompile (default-testCompile) on project selenium-jquery: Fatal error compiling: basedir /home/iode-jenkins-agent/agent/workspace/IodeSystems_SeleniumJQuery_PR-69/target/generated-test-sources/test-annotations does not exist -> [Help 1]

The configuration I have is pretty simple, no funny business:

<plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.11.0</version>
        <configuration>
          <source>21</source>
          <target>21</target>
          <showWarnings>true</showWarnings>
        </configuration>
      </plugin>

Here is the output of mvn clean install

[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  4.853 s
[INFO] Finished at: 2023-12-22T16:09:00-08:00
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.12.0:testCompile (default-testCompile) on project selenium-jquery: Fatal error compiling: basedir /Users/nthalk/local/src/iodesystems/SeleniumJQuery/target/generated-test-sources/test-annotations does not exist -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.12.0:testCompile (default-testCompile) on project selenium-jquery: Fatal error compiling
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2 (MojoExecutor.java:333)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute (MojoExecutor.java:316)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:212)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:174)
    at org.apache.maven.lifecycle.internal.MojoExecutor.access$000 (MojoExecutor.java:75)
    at org.apache.maven.lifecycle.internal.MojoExecutor$1.run (MojoExecutor.java:162)
    at org.apache.maven.plugin.DefaultMojosExecutionStrategy.execute (DefaultMojosExecutionStrategy.java:39)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
    at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
    at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
    at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
    at java.lang.reflect.Method.invoke (Method.java:580)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:283)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:226)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:407)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:348)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
    at java.lang.reflect.Method.invoke (Method.java:580)
    at org.apache.maven.wrapper.BootstrapMainStarter.start (BootstrapMainStarter.java:52)
    at org.apache.maven.wrapper.WrapperExecutor.execute (WrapperExecutor.java:161)
    at org.apache.maven.wrapper.MavenWrapperMain.main (MavenWrapperMain.java:73)
Caused by: org.apache.maven.plugin.MojoExecutionException: Fatal error compiling
    at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute (AbstractCompilerMojo.java:1189)
    at org.apache.maven.plugin.compiler.TestCompilerMojo.execute (TestCompilerMojo.java:204)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:126)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2 (MojoExecutor.java:328)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute (MojoExecutor.java:316)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:212)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:174)
    at org.apache.maven.lifecycle.internal.MojoExecutor.access$000 (MojoExecutor.java:75)
    at org.apache.maven.lifecycle.internal.MojoExecutor$1.run (MojoExecutor.java:162)
    at org.apache.maven.plugin.DefaultMojosExecutionStrategy.execute (DefaultMojosExecutionStrategy.java:39)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
    at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
    at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
    at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
    at java.lang.reflect.Method.invoke (Method.java:580)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:283)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:226)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:407)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:348)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
    at java.lang.reflect.Method.invoke (Method.java:580)
    at org.apache.maven.wrapper.BootstrapMainStarter.start (BootstrapMainStarter.java:52)
    at org.apache.maven.wrapper.WrapperExecutor.execute (WrapperExecutor.java:161)
    at org.apache.maven.wrapper.MavenWrapperMain.main (MavenWrapperMain.java:73)
Caused by: java.lang.IllegalStateException: basedir /Users/nthalk/local/src/iodesystems/SeleniumJQuery/target/generated-test-sources/test-annotations does not exist
    at org.codehaus.plexus.util.DirectoryScanner.scan (DirectoryScanner.java:268)
    at org.codehaus.plexus.compiler.AbstractCompiler.getSourceFilesForSourceRoot (AbstractCompiler.java:168)
    at org.codehaus.plexus.compiler.AbstractCompiler.getSourceFiles (AbstractCompiler.java:194)
    at org.codehaus.plexus.compiler.javac.JavacCompiler.performCompile (JavacCompiler.java:138)
    at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute (AbstractCompilerMojo.java:1186)
    at org.apache.maven.plugin.compiler.TestCompilerMojo.execute (TestCompilerMojo.java:204)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo (DefaultBuildPluginManager.java:126)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute2 (MojoExecutor.java:328)
    at org.apache.maven.lifecycle.internal.MojoExecutor.doExecute (MojoExecutor.java:316)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:212)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:174)
    at org.apache.maven.lifecycle.internal.MojoExecutor.access$000 (MojoExecutor.java:75)
    at org.apache.maven.lifecycle.internal.MojoExecutor$1.run (MojoExecutor.java:162)
    at org.apache.maven.plugin.DefaultMojosExecutionStrategy.execute (DefaultMojosExecutionStrategy.java:39)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute (MojoExecutor.java:159)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:105)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject (LifecycleModuleBuilder.java:73)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build (SingleThreadedBuilder.java:53)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute (LifecycleStarter.java:118)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:261)
    at org.apache.maven.DefaultMaven.doExecute (DefaultMaven.java:173)
    at org.apache.maven.DefaultMaven.execute (DefaultMaven.java:101)
    at org.apache.maven.cli.MavenCli.execute (MavenCli.java:906)
    at org.apache.maven.cli.MavenCli.doMain (MavenCli.java:283)
    at org.apache.maven.cli.MavenCli.main (MavenCli.java:206)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
    at java.lang.reflect.Method.invoke (Method.java:580)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced (Launcher.java:283)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch (Launcher.java:226)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode (Launcher.java:407)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main (Launcher.java:348)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:103)
    at java.lang.reflect.Method.invoke (Method.java:580)
    at org.apache.maven.wrapper.BootstrapMainStarter.start (BootstrapMainStarter.java:52)
    at org.apache.maven.wrapper.WrapperExecutor.execute (WrapperExecutor.java:161)
    at org.apache.maven.wrapper.MavenWrapperMain.main (MavenWrapperMain.java:73)

[jorsol]

@Nthalk version 3.12.1 is going to be released in a couple of days fixing that issue.

[mensinda]

I have rebased the PR and added a test case.

I am not really happy with the hardcoded paths in SourcePathReadGoal.java myself, but I couldn't figure out a better solution.

[mensinda]

Not sure why the CI failed before and the logs are gone now. I have rebased the PR and mvn -Prun-its verify ran successfully on my machine.

@elharo @slawekjaranowski There also is a test case now, as requested.

[mensinda]

@elharo I did that and there are no changes:

mvn spotless:apply:

[INFO] Scanning for projects...
[INFO]
[INFO] -----------< org.apache.maven.plugins:maven-compiler-plugin >-----------
[INFO] Building Apache Maven Compiler Plugin 3.14.1-SNAPSHOT
[INFO]   from pom.xml
[INFO] ----------------------------[ maven-plugin ]----------------------------
[INFO]
[INFO] --- spotless:2.43.0:apply (default-cli) @ maven-compiler-plugin ---
[INFO] Spotless.Java is keeping 282 files clean - 0 were changed to be clean, 0 were already clean, 282 were skipped because caching determined they were already clean
[INFO] Spotless.Pom is keeping 1 files clean - 0 were changed to be clean, 0 were already clean, 1 were skipped because caching determined they were already clean
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  1.198 s
[INFO] Finished at: 2025-02-19T14:22:35+01:00
[INFO] ------------------------------------------------------------------------

---

git status:

On branch optionalGeneratedSources
Your branch is up to date with 'origin/optionalGeneratedSources'.

nothing to commit, working tree clean

[mensinda]

Nevermind, I was using Java 17 multiline string literals in the test-case. The CI should run now.

[elharo]

Is the build working or is the CI borked again:

Error: Failed to execute goal com.kohlschutter.mavenplugins:copy-rename-maven-plugin:2.0.0:copy (set-source) on project code: The plugin com.kohlschutter.mavenplugins:copy-rename-maven-plugin:2.0.0 requires Maven version 3.8.8 -> [Help 1] org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal com.kohlschutter.mavenplugins:copy-rename-maven-plugin:2.0.0:copy (set-source) on project code: The plugin com.kohlschutter.mavenplugins:copy-rename-maven-plugin:2.0.0 requires Maven version 3.8.8

[mensinda]

The current error is most likely because of the copy-rename-maven-plugin that I require for the IT to function.

I have added invoker.maven.version = 3.8.8+ to the properties to (hopefully) skip the test on the CIs with maven 3.6.3.

[mensinda]

looks like the CI is green now.

[desruisseaux]

Should we try to add the same test to master branch?

Probably. It is desirable that the master contains most of the tests of the 3.x branch.

[oehme]

The PR description says

The generatedSourcesPath will still be added to the maven project paths.

But this is not the case, the entire code related to source paths was removed. This means that downstream plugins no longer see the generated sources. For example, the source-jar will no longer contain the generated sources. I'm pretty sure that's not what you wanted and will upset anyone who relies on https://issues.apache.org/jira/browse/MCOMPILER-157. Wasn't the idea to only remove this line? That should have been enough to fix MCOMPILER-538 without any side effects.

[slawekjaranowski]

The PR descripations says

The generatedSourcesPath will still be added to the maven project paths.

But this is not the case, the entire code related to source paths was removed. This means that downstream plugins no longer see the generated sources. For example, the source-jar will no longer contain the generated sources. I'm pretty sure that's not what you wanted and will upset anyone who relies on https://issues.apache.org/jira/browse/MCOMPILER-157. Wasn't the idea to only remove this line? That should have been enough to fix MCOMPILER-538 without any side effects.

Looks like missing tests for MCOMPILER-157 ...

[oehme]

Actually, I think there is a test - SourcePathReadGoal - but that was changed as part of this PR too.

[mensinda]

Ah, it has been so long that I completely forgot about that part in the description.

Sadly, removing the generated source path from the project is required. The new testcase fails if the relevant code sections are reverted:

diff --git a/src/it/setup_annotation-verify-plugin/src/main/java/org.apache.maven.plugins.compiler.it/SourcePathReadGoal.java b/src/it/setup_annotation-verify-plugin/src/main/java/org.apache.maven.plugins.compiler.it/SourcePathReadGoal.java
index d3691fa..46b7d2b 100644
--- a/src/it/setup_annotation-verify-plugin/src/main/java/org.apache.maven.plugins.compiler.it/SourcePathReadGoal.java
+++ b/src/it/setup_annotation-verify-plugin/src/main/java/org.apache.maven.plugins.compiler.it/SourcePathReadGoal.java
@@ -47,17 +47,12 @@ public class SourcePathReadGoal extends AbstractMojo {
     public void execute() throws MojoExecutionException, MojoFailureException {
         if (sourceClass != null) {
             getLog().info("Checking compile source roots for: '" + sourceClass + "'");
-            List<String> roots = project.getCompileSourceRoots();
-            roots.add(project.getModel().getBuild().getOutputDirectory() + "/../generated-sources/annotations");
-            assertGeneratedSourceFileFor(sourceClass, roots);
+            assertGeneratedSourceFileFor(sourceClass, project.getCompileSourceRoots());
         }

         if (testSourceClass != null) {
             getLog().info("Checking test-compile source roots for: '" + testSourceClass + "'");
-            List<String> roots = project.getTestCompileSourceRoots();
-            roots.add(
-                    project.getModel().getBuild().getOutputDirectory() + "/../generated-test-sources/test-annotations");
-            assertGeneratedSourceFileFor(testSourceClass, roots);
+            assertGeneratedSourceFileFor(testSourceClass, project.getTestCompileSourceRoots());
         }
     }

diff --git a/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java b/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java
index 5631892..8a94573 100644
--- a/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java
+++ b/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java
@@ -824,6 +824,26 @@ public abstract class AbstractCompilerMojo extends AbstractMojo {
             }
         }

+        String generatedSourcesPath = generatedSourcesDirectory.getAbsolutePath();
+
+        if (isTestCompile()) {
+            getLog().debug("Adding " + generatedSourcesPath + " to test-compile source roots:\n  "
+                    + StringUtils.join(project.getTestCompileSourceRoots().iterator(), "\n  "));
+
+            project.addTestCompileSourceRoot(generatedSourcesPath);
+
+            getLog().debug("New test-compile source roots:\n  "
+                    + StringUtils.join(project.getTestCompileSourceRoots().iterator(), "\n  "));
+        } else {
+            getLog().debug("Adding " + generatedSourcesPath + " to compile source roots:\n  "
+                    + StringUtils.join(project.getCompileSourceRoots().iterator(), "\n  "));
+
+            project.addCompileSourceRoot(generatedSourcesPath);
+
+            getLog().debug("New compile source roots:\n  "
+                    + StringUtils.join(project.getCompileSourceRoots().iterator(), "\n  "));
+        }
+
         compilerConfiguration.setSourceLocations(compileSourceRoots);

         compilerConfiguration.setAnnotationProcessors(annotationProcessors);

[mensinda]

I did manage to add the path back in #311, but it feels hacky...

[oehme]

You can do it without these hacks by moving the generated sources code after the stale source scanning code. The important part is that it needs to happen before the mojo returns, but after it has scanned its own sources.

diff --git a/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java b/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java
index 5631892..27ea1f3 100644
--- a/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java
+++ b/src/main/java/org/apache/maven/plugin/compiler/AbstractCompilerMojo.java
@@ -814,16 +814,6 @@ public abstract class AbstractCompilerMojo extends AbstractMojo {
 
         compilerConfiguration.setProc(proc);
 
-        File generatedSourcesDirectory = getGeneratedSourcesDirectory();
-        compilerConfiguration.setGeneratedSourcesDirectory(
-                generatedSourcesDirectory != null ? generatedSourcesDirectory.getAbsoluteFile() : null);
-
-        if (generatedSourcesDirectory != null) {
-            if (!generatedSourcesDirectory.exists()) {
-                generatedSourcesDirectory.mkdirs();
-            }
-        }
-
         compilerConfiguration.setSourceLocations(compileSourceRoots);
 
         compilerConfiguration.setAnnotationProcessors(annotationProcessors);
@@ -933,9 +923,6 @@ public abstract class AbstractCompilerMojo extends AbstractMojo {
                     getLog().info("Recompiling the module because of "
                             + MessageUtils.buffer().strong(cause) + ".");
                     compilerConfiguration.setSourceFiles(sources);
-                } else {
-                    getLog().info("Nothing to compile - all classes are up to date.");
-                    return;
                 }
             } catch (CompilerException e) {
                 throw new MojoExecutionException("Error while computing stale sources.", e);
@@ -964,11 +951,6 @@ public abstract class AbstractCompilerMojo extends AbstractMojo {
                 throw new MojoExecutionException("Error while computing stale sources.", e);
             }
 
-            if (staleSources.isEmpty()) {
-                getLog().info("Nothing to compile - all classes are up to date.");
-                return;
-            }
-
             compilerConfiguration.setSourceFiles(staleSources);
 
             try {
@@ -988,6 +970,41 @@ public abstract class AbstractCompilerMojo extends AbstractMojo {
             }
         }
 
+        File generatedSourcesDirectory = getGeneratedSourcesDirectory();
+        compilerConfiguration.setGeneratedSourcesDirectory(
+                generatedSourcesDirectory != null ? generatedSourcesDirectory.getAbsoluteFile() : null);
+
+        if (generatedSourcesDirectory != null) {
+            if (!generatedSourcesDirectory.exists()) {
+                generatedSourcesDirectory.mkdirs();
+            }
+
+            String generatedSourcesPath = generatedSourcesDirectory.getAbsolutePath();
+
+            if (isTestCompile()) {
+                getLog().debug("Adding " + generatedSourcesPath + " to test-compile source roots:\n  "
+                        + StringUtils.join(project.getTestCompileSourceRoots().iterator(), "\n  "));
+
+                project.addTestCompileSourceRoot(generatedSourcesPath);
+
+                getLog().debug("New test-compile source roots:\n  "
+                        + StringUtils.join(project.getTestCompileSourceRoots().iterator(), "\n  "));
+            } else {
+                getLog().debug("Adding " + generatedSourcesPath + " to compile source roots:\n  "
+                        + StringUtils.join(project.getCompileSourceRoots().iterator(), "\n  "));
+
+                project.addCompileSourceRoot(generatedSourcesPath);
+
+                getLog().debug("New compile source roots:\n  "
+                        + StringUtils.join(project.getCompileSourceRoots().iterator(), "\n  "));
+            }
+        }
+
+        if (compilerConfiguration.getSourceFiles().isEmpty()) {
+            getLog().info("Nothing to compile - all classes are up to date.");
+            return;
+        }
+

[mensinda]

@oehme Thanks for the idea, I have added an alternative implementation / fix with #312.