seems the newer compiler plugin has become more picky

src/etc/poms/ant-apache-resolver/pom.xml

@@ -55,7 +55,7 @@ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/ma
         <artifactId>maven-compiler-plugin</artifactId>
         <configuration>
           <includes>
-            <include>org/apache/tools/ant/types/resolver/**</include>
+            <include>org/apache/tools/ant/types/resolver/*.java</include>
           </includes>
         </configuration>
       </plugin>