In a Cocoa project, you can mix Java2 and Objective-C classes. So my project is in Objective-C but to access to a PostgreSQLdatabase, it will be use now a Java2 class. Thanks for the link : http://www.j-elite.com/pgprimer/
pgsql-jdbc by date:
Соглашаюсь с условиями обработки персональных данных