@Test
public void getPropertyKeyList_shouldReturnTwo() throws Exception {
pb.addProperty("test", "42");
pb.addProperty("number", 42);
Set<String> list = pb.propertyKeySet();
assertThat(list.size(), is(2));
}
@Test
public void removeProperty_shouldContainStringOnly() throws Exception {
pb.addProperty("number", 42);
pb.addProperty("string", "42");
pb.removeProperty("number");
Set<String> list = pb.propertyKeySet();
assertTrue(list.contains("string"));
assertFalse(list.contains("number"));
}