jai change mon algo, le voici.....
private
DefaultMutableTreeNode createNodes(Iterator i,DefaultMutableTreeNode racine) {
DefaultMutableTreeNode noeud = null;
XmlLogLine tmp = null;
while(i.hasNext()){
tmp = (XmlLogLine)i.next();
racine.setAllowsChildren(true);
noeud = new DefaultMutableTreeNode(tmp.getLog_method());
if(tmp.isStart() && !(tmp.isStartStop())){
racine.add(noeud);
racine=noeud;
}
elseif(tmp.isStop() && !(tmp.isStartStop())){
racine=(DefaultMutableTreeNode)racine.getParent();
}
elseif(tmp.isStartStop()){
racine.add(noeud);
}
}
return racine;
}