Sample JPA project and how to input data in MySQL database
MySQL users table schema
mysql> describe users; +----------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+---------+------+-----+---------+----------------+ | uid | int(11) | NO | PRI | NULL | auto_increment | | username | text | NO | | NULL | | | password | text | NO | | NULL | | +----------+---------+------+-----+---------+----------------+
After creating the table manually with the Open SQL Scrapbook view, create entities from tables
Just right-click on your project folder and under JPA Tools, select Create Entities from Tables.
This should create a User.java class.
Class to input data
package siamwebdb;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
public class TestDB {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
EntityManagerFactory emf = Persistence.createEntityManagerFactory("siamweb");
EntityManager em = emf.createEntityManager();
User myuser = new User();
myuser.setUsername("joe");
myuser.setPassword("heehee");
EntityTransaction trans = em.getTransaction();
trans.begin();
em.persist(myuser);
trans.commit();
}
}
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
public class TestDB {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
EntityManagerFactory emf = Persistence.createEntityManagerFactory("siamweb");
EntityManager em = emf.createEntityManager();
User myuser = new User();
myuser.setUsername("joe");
myuser.setPassword("heehee");
EntityTransaction trans = em.getTransaction();
trans.begin();
em.persist(myuser);
trans.commit();
}
}
persistence.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" 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_1_0.xsd">
<persistence-unit name="siamweb">
<class>siamwebdb.User</class>
<properties>
<property name="eclipselink.jdbc.url" value="jdbc:mysql://localhost:3306/siamwebdb"/>
<property name="eclipselink.jdbc.user" value="root"/>
<property name="eclipselink.jdbc.password" value="x38slhl9secretpasswordlialweihl"/>
<property name="eclipselink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
</properties>
</persistence-unit>
</persistence>
<persistence version="1.0" 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_1_0.xsd">
<persistence-unit name="siamweb">
<class>siamwebdb.User</class>
<properties>
<property name="eclipselink.jdbc.url" value="jdbc:mysql://localhost:3306/siamwebdb"/>
<property name="eclipselink.jdbc.user" value="root"/>
<property name="eclipselink.jdbc.password" value="x38slhl9secretpasswordlialweihl"/>
<property name="eclipselink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
</properties>
</persistence-unit>
</persistence>
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