@ElementCollection is new annotation introduced in JPA 2.0, This will help us get rid of One-Many and Many-One shitty syntax. Example 1: Stores list of Strings in an Entity @Entity public class Users implements Serializable { private static final long serialVersionUID = 1L; @Id @GeneratedValue(strategy = GenerationType.AUTO) private Long id; @ElementCollection private List<String> certifications = new ArrayList <String> (); public Long getId() { return id; } public void setId(Long id) { this.id = id; } public List <String> getCertifications() { return certifications; } pub...
According to JPA specification we can define multiple "persistence-unit" elements (i.e. like below) in persistence.xml file and can easily refer them inside Dao layers as this. public class PolarDaoImpl { @PersistenceContext(unitName="PolarPU") protected EntityManager entityManager; -- } public class BearDaoImpl { @PersistenceContext(unitName="BearPU") protected EntityManager entityManager; -- } Checkout sample persistence.xml <?xml version="1.0" encoding="UTF-8"?> <persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"> <!-- Database 1 --> <persistence-unit name="PolarPU" transaction-type="RESOURCE_LOCAL"> ...
What is CsvValidator ? A Java framework which validates any CSV files something similar to XML validation using XSD. Why should I use this ? You don't have to use this and in fact its easy to write something your own and also checkout its source code for reference. Why did I write this ? Some of our projects integrate with third party application which exchanges information in CSV files so I thought of writing a generic validator which can be hooked in multiple projects or can be used by QA for integration testing. What is the license clause ? GNU GPL v2 Are there any JUnit test cases for me checkout ? Yes, source How to integrate in my existing project ? Just add the Jar which can be downloaded from here CsvValidator.jar and you are good. Instantiate CsvValidator c onstructor which takes these 3 arguements // filename is the the file to be validated and here ...
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