private void processFilterNode(ModuleDescriptor node, Collection toKeep, Map moduleIdMap) {
private void processFilterNode(ModuleDescriptor node, Set toKeep, Map moduleIdMap) {
    private void processFilterNode(ModuleDescriptor node, Collection toKeep, Map moduleIdMap) {        toKeep.add(node);        DependencyDescriptor[] deps = node.getDependencies();        for (int i=0; i<deps.length; i++) {            ModuleId id = deps[i].getDependencyId();            if (moduleIdMap.get(id) != null) {                processFilterNode((ModuleDescriptor) moduleIdMap.get(id), toKeep, moduleIdMap);            }        }    }