move module-info.java out of the java directory to avoid problems in eclipse

Author: rbri

pom.xml

@@ -37,6 +37,7 @@
 
         <!-- plugins -->
         <central-publishing-plugin.version>0.10.0</central-publishing-plugin.version>
+        <build-helper-plugin.version>3.6.1</build-helper-plugin.version>
         <checkstyle-plugin.version>3.6.0</checkstyle-plugin.version>
         <pmd-plugin.version>3.28.0</pmd-plugin.version>
         <spotbugs-plugin.version>4.9.8.2</spotbugs-plugin.version>
@@ -72,6 +73,26 @@
 
     <build>
         <plugins>
+            <plugin>
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>build-helper-maven-plugin</artifactId>
+                <version>${build-helper-plugin.version}</version>
+                <executions>
+                    <execution>
+                        <id>add-module-source</id>
+                        <phase>generate-sources</phase>
+                        <goals>
+                            <goal>add-source</goal>
+                        </goals>
+                        <configuration>
+                            <sources>
+                                <source>src/main/module-info</source>
+                            </sources>
+                        </configuration>
+                    </execution>
+                </executions>
+            </plugin>
+
             <plugin>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>${compiler-plugin.version}</version>

src/main/java/module-info.java src/main/module-info/module-info.javasrc/main/java/module-info.java renamed to src/main/module-info/module-info.java

@@ -0,0 +1,29 @@
+# Module Info Directory
+
+This directory contains the `module-info.java` file for the Java Platform Module System (JPMS).
+
+## Why is this in a separate directory?
+
+The `module-info.java` file is kept separate from `src/main/java/` for the following reasons:
+
+1. **Eclipse IDE Compatibility**: Eclipse has known issues with Java modules, particularly when the project uses older Java versions or has complex module configurations. Keeping `module-info.java` separate prevents Eclipse from attempting to process it during development.
+
+2. **Build-Time Integration**: The module descriptor is added to the compilation during the Maven build process via the `build-helper-maven-plugin`, which adds this directory as a source folder only during the build.
+
+3. **IDE Independence**: This approach allows developers to use Eclipse without module-related compilation errors while still producing proper modular JARs when building with Maven.
+
+## How it works
+
+The Maven build process:
+1. Compiles all regular Java sources from `src/main/java/`
+2. Adds `src/main/module-info/` as an additional source directory
+3. Compiles `module-info.java` 
+4. Packages everything into a proper modular JAR
+
+## For Developers
+
+- **Eclipse users**: You don't need to worry about this file - Eclipse won't see it
+- **IntelliJ users**: IntelliJ handles modules better and can work with this setup
+- **Maven builds**: The module descriptor is automatically included in the final JAR
+
+If you need to modify the module descriptor, edit `src/main/module-info/module-info.java` directly.