2.3. Caching and Retrieving Data

   // Let us get a hold of the root node.
   Node rootNode = cache.getRoot();

   // Remember, JBoss Cache stores data in a tree structure.
   // All nodes in the tree structure are identified by Fqn objects.
   Fqn peterGriffinFqn = Fqn.fromString("/griffin/peter");

   // Create a new Node
   Node peterGriffin = rootNode.addChild(peterGriffinFqn);

   // let us store some data in the node
   peterGriffin.put("isCartoonCharacter", Boolean.TRUE);
   peterGriffin.put("favoriteDrink", new Beer());

   // some tests (just assume this code is in a JUnit test case)
   assertTrue(peterGriffin.get("isCartoonCharacter"));
   assertEquals(peterGriffinFqn, peterGriffin.getFqn());
   assertTrue(rootNode.hasChild(peterGriffinFqn));

   Set keys = new HashSet();
   keys.add("isCartoonCharacter");
   keys.add("favoriteDrink");

   assertEquals(keys, peterGriffin.getKeys());

   // let us remove some data from the node
   peterGriffin.remove("favoriteDrink");

   assertNull(peterGriffin.get("favoriteDrink");

   // let us remove the node altogether
   rootNode.removeChild(peterGriffinFqn);

   assertFalse(rootNode.hasChild(peterGriffinFqn));

   Fqn peterGriffinFqn = Fqn.fromString("/griffin/peter");

   cache.put(peterGriffinFqn, "isCartoonCharacter", Boolean.TRUE);
   cache.put(peterGriffinFqn, "favoriteDrink", new Beer());

   assertTrue(peterGriffin.get(peterGriffinFqn, "isCartoonCharacter"));
   assertTrue(cache.getRootNode().hasChild(peterGriffinFqn));

   cache.remove(peterGriffinFqn, "favoriteDrink");

   assertNull(cache.get(peterGriffinFqn, "favoriteDrink");

   cache.removeNode(peterGriffinFqn);

   assertFalse(cache.getRootNode().hasChild(peterGriffinFqn));