@Test public void testGetInstance() { final NullNode instance = NullNode.getInstance(); assertNotNull(instance); assertSame(instance, NullNode.getInstance()); }
public static NullNode getInstance() { return instance; }
NullNode implements Node { public static NullNode getInstance() { return instance; } }
NullNode implements Node { public static NullNode getInstance() { return instance; } private  NullNode(); }
NullNode implements Node { public static NullNode getInstance() { return instance; } private  NullNode(); static NullNode getInstance(); @Override int getTreeSize(); @Override Node getLeft(); @Override Node getRight(); @Override String getName(); @Override void walk(); }
NullNode implements Node { public static NullNode getInstance() { return instance; } private  NullNode(); static NullNode getInstance(); @Override int getTreeSize(); @Override Node getLeft(); @Override Node getRight(); @Override String getName(); @Override void walk();  }