@Test
public void testMint_returns_existing_DOI()
        throws SQLException, AuthorizeException, IOException, IdentifierException, WorkflowException, IllegalAccessException
{

    Item item = newItem();
    String doi = this.createDOI(item, null, true);
    
    String retrievedDOI = provider.mint(context, item);
    assertNotNull("Minted DOI is null?!", retrievedDOI);
    assertEquals("Mint did not returned an existing DOI!", doi, retrievedDOI);
}