--- a/src/main/java/de/mpiwg/itgroup/annotations/neo4j/AnnotationStore.java	Sun Sep 23 16:28:05 2012 +0200
+++ b/src/main/java/de/mpiwg/itgroup/annotations/neo4j/AnnotationStore.java	Mon Sep 24 11:36:33 2012 +0200
@@ -178,6 +178,42 @@
     }
     
     /**
+     * Add Person newMember to Group group.
+     * 
+     * @param group
+     * @param member
+     */
+    public Person addGroupMember(Group group, Person member) {
+        Node gn = getActorNode(group);
+        Node pn = getActorNode(member);
+        Person addedMember = null;
+        if (gn != null && pn != null) {
+            getOrCreateRelation(pn, RelationTypes.MEMBER_OF, gn);
+            addedMember = member;
+        }
+        return addedMember;
+    }
+    
+    /**
+     * Delete Person oldMember from Group group.
+     * 
+     * @param group
+     * @param member
+     */
+    public void deleteGroupMember(Group group, Person member) {
+        Node gn = getActorNode(group);
+        Iterable<Relationship> rels = gn.getRelationships(RelationTypes.MEMBER_OF);
+        for (Relationship rel : rels) {
+            Node mn = rel.getStartNode();
+            if (mn.equals(member)) {
+                rel.delete();
+                // there should be only one
+                break;
+            }
+        }        
+    }
+    
+    /**
      * Returns the stored Actor matching the given one.
      * 
      * @param actor

--- a/src/main/java/de/mpiwg/itgroup/annotations/restlet/annotations_ui/GroupMembersResource.java	Sun Sep 23 16:28:05 2012 +0200
+++ b/src/main/java/de/mpiwg/itgroup/annotations/restlet/annotations_ui/GroupMembersResource.java	Mon Sep 24 11:36:33 2012 +0200
@@ -47,12 +47,14 @@
         result += String.format("<p>Group: %s <a href=\"%s\">(%s)</a></p>\n", group.getName(), groupsUrl, group.getId());
         result += "<p>Members:</p>\n";
         result += "<table>";
+        result += String.format("<form method=\"post\" action=\"%s\">", thisUrl);
         List<Person> members = store.getMembersOfGroup(group);
         for (Person p : members) {
             result += String.format("<tr><td>%s</td><td>(%s)</td>", p.getName(), p.getIdString());
-            //result += String.format("<td></td></tr>\n", p.getName(), p.getIdString());
+            result += String.format("<td><input type=\"submit\" name=\"del_member\" value=\"delete:%s\"></td></tr>\n", p.getIdString());
         }
         result += "</table>\n";
+        result += "</form>\n";
         result += String.format("<form method=\"post\" action=\"%s\">\n", thisUrl);
         result += "<p>Add new member: <select name=\"add_member\">\n";
         for (Actor p : store.getActors("uri", "*", NodeTypes.PERSON)) {
@@ -84,7 +86,18 @@
             setStatus(Status.CLIENT_ERROR_BAD_REQUEST);
             return null;
         }
-        
+        if (addMemberId != null) {
+            logger.debug("adding member: "+addMemberId);
+            Person member = new Person(addMemberId);
+            store.addGroupMember(group, member);
+        } else if (delMemberId != null) {
+            if (delMemberId.startsWith("delete:")) {
+                delMemberId = delMemberId.substring(7);
+            }
+            logger.debug("deleting member: "+delMemberId);
+            Person member = new Person(delMemberId);
+            store.deleteGroupMember(group, member);
+        }
         // return 303: see other
         setStatus(Status.REDIRECTION_SEE_OTHER);
         // go get same URL