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Showing posts from November, 2015

Vaadin JPA Container Example

Simple example showing how to use a Vaadin JPA Container The scenario is a Customer entity in a database. You have a use case which requires the retrieval of a customer record by Name and By Number. 1) Set up a Entity Manager private final EntityManager em; 2) Create the Entity Manager from the persistence unit em = JPAContainerFactory.createEntityManagerForPersistenceUnit(< name of persistence unit >); 3) Get Customer By Number - returns a JPA Container which is useful for Vaadin Tables public JPAContainer getCustomerByNumber(String aCustomerNumber) { JPAContainer customer = JPAContainerFactory.make(Customer.class, em); Container.Filter filter = new Compare.Equal("number", aCustomerNumber); customer.addContainerFilter(filter); return customer; } 4) Get Customer By Name - uses JPA named query public Customer getCustomerByName(String aCustomerName) { Query queryCustomerByName = em.createN