NVDA doesn't announce the level of tree nodes within java swing apps.
steps to reproduce:

• download swingset2:
  https://java.net/projects/ojt-accessibility/downloads/directory/Demos
• run the downloaded jar file and NVDA as well
• from the toolbar, click the JTree demo toggle button
• navagate to the tree view and move the focus between the nodes using arrow keys

expected result:
the node content is announced besides the level also
observed result:
the level is not announced

NVDA version: 2015.4
windows 7 64bit
JDK 8u74

note:
there is another issue here with expand / collaps events of the node. think reporting this in other separate issue is better in a case this problem is NVDA specific