public Field findSingletonStaticPrivateInstanceField() {
for (Field field : Earth.class.getDeclaredFields()) {
if (field.getType() == Earth.class) {
return field;
}
}
return null;
}
@Test
public void checkThatSingletonContainsStaticPrivateInstanceField() {
Field field = findSingletonStaticPrivateInstanceField();
assertNotNull("No static private instance field found.", field);
assertTrue(
"Field pointing to the Earth instance should be static",
Modifier.isStatic(field.getModifiers()));
assertTrue(
"Field pointing to the Earth instance should be private",
Modifier.isPrivate(field.getModifiers()));
}
private void replaceEarth(String earthclass) throws Exception {
System.setProperty("earthclass", earthclass);
Field instance = findSingletonStaticPrivateInstanceField();
instance.setAccessible(true);
instance.set(null, null);
}