Update parent POM version.
diff --git a/pom.xml b/pom.xml
index d9629bf..98e8d5b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -22,7 +22,7 @@
     <parent>
         <groupId>org.apache</groupId>
         <artifactId>apache</artifactId>
-        <version>18</version>
+        <version>20</version>
     </parent>
     <groupId>org.apache.ws</groupId>
     <artifactId>ws-parent</artifactId>