MappingNode mappingTree = new MappingNode(rootMapping);
LinkedEngine rootEngine = new LinkedEngine(null, new RootEngine(instructionExecutor),
mappingTree);
mappingTree.getMiddleEngines().addEngine(ReqMethod.ALL, rootEngine);
TreeBuilder treeBuilder = new TreeBuilder();
treeBuilder.create(mappingTree, modules);
return mappingTree;
}