To implement your own tree popUp menu for any tree node, one need to extend from class "com.jaxfront.swing.ui.editor.AbstractPopUpMenu". 
See class com.jaxfront.demo.api.OwnTreePopUpMenu
public class OwnTreePopUpMenu extends AbstractPopUpMenu {
public OwnTreePopUpMenu(NavigationTree tree, com.jaxfront.core.ui.TreeNode treeNode) {
super(tree, treeNode);
initialize();
}
private void initialize() {
OwnSwingTestAction testAction = new OwnSwingTestAction("test");
testAction.putValue(XUITypes.VALUE_DOM, getTreeNode().getType().getDOM());
testAction.putValue(XUITypes.VALUE_SOURCE, getTreeNode().getType());
add(testAction);
}
}