MySQL Cluster Tutorial - cdn.oreillystatic.com

Main.java (part 1):
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
import javax.persistence.Query;
import java.io.*;
public class Main {
public static void main (String[] args) throws java.io.IOException {
EntityManagerFactory entityManagerFactory =
Persistence.createEntityManagerFactory("clusterdb");
EntityManager em = entityManagerFactory.createEntityManager();
EntityTransaction userTransaction = em.getTransaction();
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("The tables will now have been created - check through
SQL.");
System.out.println("mysql> use clusterdb;");
System.out.println("mysql> show tables;");
System.out.println("Hit return when you are done");
String ignore = br.readLine();
As part of creating the EntityManagerFactory and EntityManager, OpenJPA creates the
tables for the two classes specified for the ‘clusterdb’ persistence unit. While the
application waits for the user to press return, this can be checked:
mysql> use clusterdb
mysql> show tables;
+---------------------+
| Tables_in_clusterdb |
+---------------------+
| department |
| employee |
+---------------------+
After hitting return, the application can create an Employee object and then persist it – at
which point it will be stored in the ‘employee’ table. A second Employee object is then
created and populated with the data read back from the database (using a primary key look
up on the Id property with a value of 1):
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