fix modularity for Java 9 (#310)

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>com.kttdevelopment</groupId>
     <artifactId>mal4j</artifactId>
-    <version>2.7.3</version>
+    <version>2.7.4</version>
 
     <profiles>
         <profile>
@@ -71,8 +71,8 @@
             </distributionManagement>
         </profile>
         <profile>
-            <!-- disable javadoc on java 8 -->
-            <id>java8</id>
+            <!-- do not generate javadoc on Java 8 -->
+            <id>skip-javadoc</id>
             <activation>
                 <jdk>(,8]</jdk>
             </activation>
@@ -92,10 +92,10 @@
             </build>
         </profile>
         <profile>
-            <!-- java 9 for modularity -->
-            <id>java9</id>
+            <!-- modularity -->
+            <id>modules</id>
             <activation>
-                <jdk>[9,)</jdk>
+                <jdk>[11,)</jdk> <!-- requires at least Java 11 to compile correctly -->
             </activation>
             <build>
                 <pluginManagement>
@@ -104,7 +104,9 @@
                             <groupId>org.apache.maven.plugins</groupId>
                             <artifactId>maven-compiler-plugin</artifactId>
                             <executions>
+                                <!-- java 9 for modularity -->
                                 <execution>
+                                    <id>java9</id>
                                     <phase>compile</phase>
                                     <goals>
                                         <goal>compile</goal>
@@ -118,26 +120,9 @@
                                         <multiReleaseOutput>true</multiReleaseOutput>
                                     </configuration>
                                 </execution>
-                            </executions>
-                        </plugin>
-                    </plugins>
-                </pluginManagement>
-            </build>
-        </profile>
-        <profile>
-            <!-- java 11 for java.net.http -->
-            <id>java11</id>
-            <activation>
-                <jdk>[11,)</jdk>
-            </activation>
-            <build>
-                <pluginManagement>
-                    <plugins>
-                        <plugin>
-                            <groupId>org.apache.maven.plugins</groupId>
-                            <artifactId>maven-compiler-plugin</artifactId>
-                            <executions>
+                                <!-- java 11 for java.net.http -->
                                 <execution>
+                                    <id>java11</id>
                                     <phase>compile</phase>
                                     <goals>
                                         <goal>compile</goal>
@@ -304,4 +289,4 @@
         </dependency>
     </dependencies>
 
-</project>
+</project>