IO-747 Enable moditect plugin when building with Java 9+

Enforce that Java 9+ is being used for releases

Suggested-by: Jochen Wiedmann at https://github.com/apache/commons-io/pull/268/files#r707160987

Author: martin-g

pom.xml

@@ -338,16 +338,16 @@ file comparators, endian transformation classes, and much more.
     <commons.jacoco.version>0.8.7</commons.jacoco.version>
     <commons.surefire.version>3.0.0-M5</commons.surefire.version>
     <commons.japicmp.version>0.15.3</commons.japicmp.version>
+    <commons.enforcer.version>3.0.0</commons.enforcer.version>
+    <commons.moditect.version>1.0.0.RC1</commons.moditect.version>
     <spotbugs.plugin.version>4.3.0</spotbugs.plugin.version>
     <spotbugs.impl.version>4.4.1</spotbugs.impl.version>
-    <jmh.version>1.33</jmh.version>    
+    <jmh.version>1.33</jmh.version>
     <japicmp.skip>false</japicmp.skip>
     <jacoco.skip>${env.JACOCO_SKIP}</jacoco.skip>
     <commons.release.isDistModule>true</commons.release.isDistModule>
-    <commons.releaseManagerName>Gary Gregory</commons.releaseManagerName>    
+    <commons.releaseManagerName>Gary Gregory</commons.releaseManagerName>
     <commons.releaseManagerKey>86fdc7e2a11262cb</commons.releaseManagerKey>
-    <moditect-maven-plugin.version>1.0.0.RC1</moditect-maven-plugin.version>
-    <moditect.skip>true</moditect.skip>
   </properties>
 
   <build>
@@ -389,7 +389,7 @@ file comparators, endian transformation classes, and much more.
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-enforcer-plugin</artifactId>
-        <version>3.0.0</version>
+        <version>${commons.enforcer.version}</version>
         <executions>
           <execution>
             <id>enforce-maven</id>
@@ -489,30 +489,6 @@ file comparators, endian transformation classes, and much more.
         <groupId>com.github.siom79.japicmp</groupId>
         <artifactId>japicmp-maven-plugin</artifactId>
       </plugin>
-      <plugin>
-        <groupId>org.moditect</groupId>
-        <artifactId>moditect-maven-plugin</artifactId>
-        <version>${moditect-maven-plugin.version}</version>
-        <executions>
-          <execution>
-            <id>add-module-infos</id>
-            <phase>package</phase>
-            <goals>
-              <goal>add-module-info</goal>
-            </goals>
-            <configuration>
-              <jvmVersion>9</jvmVersion>
-              <outputDirectory>${project.build.directory}</outputDirectory>
-              <overwriteExistingFiles>true</overwriteExistingFiles>
-              <module>
-                <moduleInfo>
-                  <name>org.apache.commons.io</name>
-                </moduleInfo>
-              </module>
-            </configuration>
-          </execution>
-        </executions>
-      </plugin>
     </plugins>
   </build>
 
@@ -589,7 +565,36 @@ file comparators, endian transformation classes, and much more.
       <properties>
         <!-- coverall version 4.3.0 does not work with java 9, see https://github.com/trautonen/coveralls-maven-plugin/issues/112 -->
         <coveralls.skip>true</coveralls.skip>
+        <maven.compiler.release>8</maven.compiler.release>
       </properties>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.moditect</groupId>
+            <artifactId>moditect-maven-plugin</artifactId>
+            <version>${commons.moditect.version}</version>
+            <executions>
+              <execution>
+                <id>add-module-infos</id>
+                <phase>package</phase>
+                <goals>
+                  <goal>add-module-info</goal>
+                </goals>
+                <configuration>
+                  <jvmVersion>9</jvmVersion>
+                  <outputDirectory>${project.build.directory}</outputDirectory>
+                  <overwriteExistingFiles>true</overwriteExistingFiles>
+                  <module>
+                    <moduleInfo>
+                      <name>org.apache.commons.io</name>
+                    </moduleInfo>
+                  </module>
+                </configuration>
+              </execution>
+            </executions>
+          </plugin>
+        </plugins>
+      </build>
     </profile>
     <profile>
       <id>benchmark</id>
@@ -632,11 +637,30 @@ file comparators, endian transformation classes, and much more.
     </profile>
     <profile>
       <id>release</id>
-      <properties>
-        <!-- Enable Moditect for releases. This requires JDK 9+ for the build -->
-        <moditect.skip>false</moditect.skip>
-        <maven.compiler.release>8</maven.compiler.release>
-      </properties>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-enforcer-plugin</artifactId>
+            <version>${commons.enforcer.version}</version>
+            <executions>
+              <execution>
+                <id>enforce-versions</id>
+                <goals>
+                  <goal>enforce</goal>
+                </goals>
+                <configuration>
+                  <rules>
+                   <requireJavaVersion>
+                      <version>9</version>
+                    </requireJavaVersion>
+                  </rules>
+                </configuration>
+              </execution>
+            </executions>
+          </plugin>
+        </plugins>
+      </build>
     </profile>
   </profiles>
 </project>