How do multiple tool windows communicate with each other?

I have two tool windows. One contains a JTree and the other contains a JTable. I'd like to notify the JTable tool window to display details from the node selected in the tree whenever the selection changes. I'm not sure how (or where) that communication takes place.

I've got a class implementing ToolWindowFactory for each tool window and both are defined in my plugin.xml

  <extensions defaultExtensionNs="com.intellij">
    <!-- Add your extensions here -->
      <toolWindow
          id="CRX Repository Tree"
          anchor="left"
          secondary="true"
          factoryClass="com.meredith.devtools.intellij.crx.toolwindow.CRXTreeToolWindowFactory">
      </toolWindow>
      <toolWindow
          id="CRX Property View"
          anchor="bottom"
          secondary="true"
          factoryClass="com.meredith.devtools.intellij.crx.toolwindow.CrxPropertyToolWindowFactory">
      </toolWindow>
  </extensions>

I'm also capturing the JTree selection change. How do I get a reference to my tool windows from my listener class, and once I have the ToolWindow reference what do I have to do to get to my JTable.

Thanks!

Todd