assertTrue("child node x/y should be present", builder.child("x")
.hasChildNode("y"));
assertTrue("child node x/y/z should be present", builder.child("x")
.child("y").hasChildNode("z"));
builder.removeNode("x");
assertFalse("child node x not should be present",
builder.hasChildNode("x"));
assertFalse("child node x/y not should be present", builder.child("x")
.hasChildNode("y"));