MockResultSet

MockResultSet is an implementation of java.sql.ResultSet backed by CSV data. It was conceived to overcome infrastructure limitations such as database server or VPN unavailability.

MockResultSet allows programmers to go ahead with work even without a database server to run SQL queries. If a CSV file containing query results is available, a database connection can be easily emulated so that system layers depending on the data (e.g., reports) can still be developed and tested.

Example

Suppose some SELECT statement results in the this data, stored in data.csv.

"id","parent_id","creation_date","name","balance"
8,,2000-03-01,"John McHidden",310
9,,2005-04-01,"Jane McFound",-256
10,,2007-10-01,"von Hidden, Stuart",180

If the database server is unreachable, a ResultSet can be mocked using the CSV data, as in the code bellow.

ResultSet rs = new MockResultSet(
				new InputStreamReader(new FileInputStream("data.csv")));


while (rs.next()) {

  double balance = rs.getDouble("balance");
  Date date = rs.getDate("creation_date");

  if (balance > 0) {
    System.out.println(date + ": " + balance);
  }
}

rs.close();

When the server turns available, adapting the working code is a simple matter of replacing MockResultSet with the object returned by the JDBC driver.

---

License

MockResultSet is Free and Open Source Software released under the MIT License.