diff --git a/testdata/dot-ref/catalina.dot b/testdata/dot-ref/catalina.dot
index 9db3af7..92ab096 100644
--- a/testdata/dot-ref/catalina.dot
+++ b/testdata/dot-ref/catalina.dot
@@ -7,26 +7,28 @@
 digraph G {
 	edge [fontname="Helvetica",fontsize=10,labelfontname="Helvetica",labelfontsize=10];
 	node [fontname="Helvetica",fontsize=10,shape=plaintext];
+	nodesep=0.25;
+	ranksep=0.5;
 	// HttpResponseBase
-	c31 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> HttpResponseBase </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c31 [label=<<table title="HttpResponseBase" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> HttpResponseBase </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// HttpResponseWrapper
-	c32 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"><font face="Helvetica-Oblique"> HttpResponseWrapper </font></td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c32 [label=<<table title="HttpResponseWrapper" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"><font face="Helvetica-Oblique"> HttpResponseWrapper </font></td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// HttpResponseFacade
-	c33 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> HttpResponseFacade </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c33 [label=<<table title="HttpResponseFacade" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> HttpResponseFacade </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// ResponseWrapper
-	c34 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"><font face="Helvetica-Oblique"> ResponseWrapper </font></td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c34 [label=<<table title="ResponseWrapper" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"><font face="Helvetica-Oblique"> ResponseWrapper </font></td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// HttpResponse
-	c35 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> HttpResponse </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c35 [label=<<table title="HttpResponse" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> HttpResponse </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// ResponseBase
-	c36 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"><font face="Helvetica-Oblique"> ResponseBase </font></td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c36 [label=<<table title="ResponseBase" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"><font face="Helvetica-Oblique"> ResponseBase </font></td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// HttpServletResponse
-	c37 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> HttpServletResponse </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c37 [label=<<table title="HttpServletResponse" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> HttpServletResponse </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// ResponseFacade
-	c38 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> ResponseFacade </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c38 [label=<<table title="ResponseFacade" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> ResponseFacade </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// ServletResponse
-	c39 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> ServletResponse </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c39 [label=<<table title="ServletResponse" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> ServletResponse </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	// Response
-	c40 [label=<<table border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> Response </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
+	c40 [label=<<table title="Response" border="0" cellborder="1" cellspacing="0" cellpadding="2" port="p"><tr><td><table border="0" cellspacing="0" cellpadding="1"><tr><td align="center" balign="center"> &#171;interface&#187; </td></tr><tr><td align="center" balign="center"> Response </td></tr></table></td></tr></table>>, fontname="Helvetica", fontcolor="black", fontsize=10.0];
 	//HttpResponseBase extends ResponseBase
 	c36:p -> c31:p [dir=back,arrowtail=empty];
 	//HttpResponseBase implements HttpResponse