if(p==null) continue;
Expression tree = ExpressionBuilder.createTree(p);
System.out.println("Graph for "+ct.getName());
System.out.println(tree.toString());
Graph g = new Graph(tree);
System.out.println(g.toString());
System.out.println();
}
return 0;
} catch (SAXException e) {
// the error should have already been reported