JavaFX + Hibernate（JPA）持久性+ Derby DB [英] JavaFX + Hibernate(JPA) persistence + Derby DB

问题描述

我正在开发一个Java桌面应用程序，并对使用JavaFX非常感兴趣。我打算使用MVC架构，因为我有一些Java EE和MVC模型的经验。

我想将数据存储在嵌入式derby数据库中并使用Hibernate作为持久层，但我找不到一篇关于用hibernate和JavaFX实现MVC的好教程。

我创建了持久性文件，但我不确定如何制作它与JavaFX一起工作。在Java EE中，我注入EJB服务或DAO，但由于我的应用程序没有连接服务器，我认为我不能这样做。

有人能解释我如何实现这个目标吗？可以一起使用它们吗？

解决方案

在我的最后一个JavaFX项目中，我在服务层下创建了一个DataBroker类，可以完成数据库中的所有CRUD操作。

示例：

  public class DataBroker {
 
 private EntityManager em; 
 
 public DataBroker（）{
 init（）; 
 
 
 private void init（）{
 this.em = Persistence.createEntityManagerFactory（< NAME_OF_YOUR_PU>）。createEntityManager（）; 
} 
 
 public Person saveOrUpdate（Person entity）{
 em.getTransaction（）。begin（）; 
 T savedEntity = em.merge（entity）; 
 em.getTransaction（）。commit（）; 
返回savedEntity; 
} 
 
 public List< Person> getAllPersons（）{
 TypedQuery< Person> query = em.createNamedQuery（Person.GET_ALL，Person.class）; 
返回query.getResultList（）; 
} 
 
} 
  

如果您只需要一个DataBroker实例，如果你需要一个实例池，创建一个池，你也许可以将它实现为Singleton。这是应用服务器的优点，他为你做这一切，你只需要注释你的类或成员。

我希望这可以帮到你。

编辑/更新
这里是EclipseLink 2.1的一个工作示例，但它只是持久性提供程序，所以它也可以用于Hibernate。

我创建了一个DataBroker，如上例所示实现我的IDataBroker接口并覆盖这些方法。

IDataBroker
$ b

  import de.professional_webworkx.crm.domain.Person; 
 import java.util.List; 
 
 
 public interface IDateBroker {
 
 public abstract void saveOrUpdate（Person person）; 
 public abstract List< Person> getAllPersons（）; 
 public abstract Person getPersonById（int id）; 
 public abstract Person getPersonByEmail（String email）; 
} 
  

DataBroker - 并非每个方法都实现了.. 。

  import de.professional_webworkx.crm.domain.Person; 
 import java.util.List; 
 import javax.persistence.EntityManager; 
 import javax.persistence.Persistence; 
 
 / ** 
 * 
 * @author Patrick Ott< [e-mail]> 
 * @version 1.0 
 * / 
 public class DataBroker implements IDateBroker {
 
 private EntityManager em; 
 
 public DataBroker（）{
 em = Persistence.createEntityManagerFactory（CRMPU）。createEntityManager（）; 
 
 
 
 $ b @Override 
 public void saveOrUpdate（Person person）{
 em.getTransaction（）。begin（）; 
 em.merge（person）; 
 em.getTransaction（）。commit（）; 
} 
 
 @Override 
 public List< Person> getAllPersons（）{
抛出新的UnsupportedOperationException（还不支持。）; //要更改生成方法的主体，请选择工具|模板。 
} 
 
 @Override 
 public Person getPersonById（int id）{
 throw new UnsupportedOperationException（Not supported yet。）; //要更改生成方法的主体，请选择工具|模板。 
} 
 
 @Override 
 public Person getPersonByEmail（String email）{
 throw new UnsupportedOperationException（Not supported yet。）; //要更改生成方法的主体，请选择工具|模板。 
} 
 
 
} 
  

IPersonService接口

  import de.professional_webworkx.crm.domain.Person; 
 import java.util.List; 
 
 
 public interface IPersonService {
 
 void saveOrUpdate（Person person）; 
列表< Person> getAllPersons（）; 
 Person getPersonById（int id）; 
 Person getPersonByEmail（String email）; 
} 
  

PersonService

  import de.professional_webworkx.crm.databroker.DataBroker; 
导入de.professional_webworkx.crm.databroker.IDateBroker; 
 import de.professional_webworkx.crm.domain.Person; 
 import java.util.List; 
 
 
公共类PersonService实现IPersonService {
 
私有IDateBroker代理; 
 
 public PersonService（）{
 broker = new DataBroker（）; 
} 
 
 @Override 
 public void saveOrUpdate（Person person）{
 broker.saveOrUpdate（person）; 
} 
 
 @Override 
 public List< Person> getAllPersons（）{
 return broker.getAllPersons（）; 
} 
 
 @Override 
 public Person getPersonById（int id）{
 return broker.getPersonById（id）; 
} 
 
 @Override 
 public Person getPersonByEmail（String email）{
 return broker.getPersonByEmail（email）; 
 
 
  

我们的Domain class Person

  import java.io.Serializable; 
 import javax.persistence.Column; 
 import javax.persistence.Entity; 
 import javax.persistence.GeneratedValue; 
 import javax.persistence.GenerationType; 
 import javax.persistence.Id; 
 import javax.persistence.Table; 
 import javax.validation.constraints.NotNull; 
 import javax.validation.constraints.Size; 
 
 
 @Entity 
 @Table（name =person）
 public class Person实现Serializable {
 
 private long id; 
 private String firstName; 
 private String lastName; 
私人字符串电子邮件; 
 $ b $ public Person（）{
} 
 
 public Person（String firstName，String lastName，String eMail）{
 this.firstName = firstName; 
 this.lastName = lastName; 
 this.eMail =电子邮件; 
 
 
 $ b @Id 
 @GeneratedValue（strategy = GenerationType.AUTO）
 public long getId（）{
 return id; 
} 
 
 
 public void setId（long id）{
 this.id = id; 
 
 
 $ b @Size（min = 2，max = 255，message =输入2到255个字符！）
 @Column（name = firstname）
 @NotNull 
 public String getFirstName（）{
 return firstName; 
} 
 
 
 public void setFirstName（String firstName）{
 this.firstName = firstName; 
 
 
 $ b @Column（name =lastname）
 @NotNull 
 public String getLastName（）{
 return lastName; 
} 
 
 
 public void setLastName（String lastName）{
 this.lastName = lastName; 
} 
 
 
 @NotNull 
 public String geteMail（）{
 return eMail; 
} 
 
 
 public void seteMail（String eMail）{
 this.eMail = eMail; 
} 
 
 
} 
  

FXMLController class

  import de.professional_webworkx.crm.business.IPersonService; 
 import de.professional_webworkx.crm.business.PersonService; 
 import de.professional_webworkx.crm.domain.Person; 
 import java.net.URL; 
 import java.util.ResourceBundle; 
 import javafx.event.ActionEvent; 
 import javafx.fxml.FXML; 
 import javafx.fxml.Initializable; 
 import javafx.scene.control.Label; 
 
公共类FXMLController实现了可初始化{
 
私有IPersonService服务; 
 
 @FXML 
私有标签标签; 
 
 @FXML 
 private void handleButtonAction（ActionEvent event）{
 Person p = new Person（Demo，User，[e-mail]）; 
 service.saveOrUpdate（p）; 
 
 $ b @Override 
 public void initialize（URL url，ResourceBundle rb）{
 //获取PersonService的实例
 service = new PersonService（ ）; 
 
 
 
 
 
 
最后但并非最不重要的MainApp以启动应用程序。
  import javafx.application.Application; 
 import static javafx.application.Application.launch; 
 import javafx.fxml.FXMLLoader; 
 import javafx.scene.Parent; 
 import javafx.scene.Scene; 
 import javafx.stage.Stage; 
 
 
 public class MainApp extends Application {
 $ b $ @Override 
 public void start（Stage stage）throws Exception {
 Parent root = FXMLLoader .load（的getClass（）的getResource（ / FXML / Scene.fxml）。）; 
 
场景场景=新场景（root）; 
 scene.getStylesheets（）。add（/ styles / Styles.css）; 
 
 stage.setTitle（JavaFX and Maven）; 
 stage.setScene（scene）; 
 stage.show（）; 
} 
 
 
 public static void main（String [] args）{
 launch（args）; 
} 
 
} 
  
这是一个标准的Maven JavaFX项目使用Netbeans 8创建。如果需要，我可以将源文件上传到GitHub或其他东西。
 
 
 
数据库表将在第一次提交时创建，因为我在persistence.xml文件，即可以从文件中看到的Schema Generation 
 <？xml version =1.0encoding = UTF-8 >？; 
< persistence version =2.1xmlns =http://xmlns.jcp.org/xml/ns/persistencexmlns：xsi =http://www.w3.org/2001/XMLSchema-实例xsi：schemaLocation =http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd\"> 
< persistence-unit name =CRMPUtransaction-type =RESOURCE_LOCAL> 
< provider> org.eclipse.persistence.jpa.PersistenceProvider< / provider> 
< class> de.professional_webworkx.crm.domain.Person< / class> 
<属性> 
< property name =javax.persistence.jdbc.urlvalue =jdbc：mysql：// localhost：3306 / exampleDb？zeroDateTimeBehavior = convertToNull/> 
< property name =javax.persistence.jdbc.uservalue =user/> 
< property name =javax.persistence.jdbc.drivervalue =com.mysql.jdbc.Driver/> 
< property name =javax.persistence.jdbc.passwordvalue =pass/> 
< property name =javax.persistence.schema-generation.database.actionvalue =create/> 
< / properties> 
< / persistence-unit> 
< /余辉> 
  
所以我希望这可以帮助您创建您的项目。
 
 
 
 Patrick  
I'm developing a Java desktop application and was really interested in use JavaFX. I'm planning to use an MVC architecture because I have had some experience with Java EE and the MVC model.

I want to store data in a embedded derby database and use Hibernate as persistence layer but I can't find a great tutorial about implementing MVC with hibernate and JavaFX.

I have created the persistence file but I am not sure how to make it work with JavaFX. In Java EE I inject EJB services or DAOs but since my app is not server connected I think I can't do that. 

Can someone explain me how to achieve that? It is possible to use them together?
解决方案
In one of my last JavaFX Projects, i created under my Service Layer a DataBroker class, which could do all the CRUD Operations on the Database.

Example:
public class DataBroker {

    private EntityManager em;

    public DataBroker() {
        init();
    }

    private void init() {
        this.em = Persistence.createEntityManagerFactory("<NAME_OF_YOUR_PU>").createEntityManager();
    }

    public Person saveOrUpdate(Person entity) {
        em.getTransaction().begin();
        T savedEntity = em.merge(entity);
        em.getTransaction().commit();
        return savedEntity;
    }

    public List<Person> getAllPersons() {
        TypedQuery<Person> query = em.createNamedQuery(Person.GET_ALL, Person.class);
        return query.getResultList();
    }

}
If you only need one DataBroker Instance, you maybe can realize it as a Singleton, if you need a Pool of Instances, create a Pool. This is the advantage of a Application Server, he does this all for you and you only have to annotate your Classes or Members. 

I hope this will help you.

EDIT / UPDATE
Here is a working example with EclipseLink 2.1, but it is only the Persistence Provider, so it works also with Hibernate.

I created a DataBroker like in the above example which implements my IDataBroker Interface and overrides the methods.

IDataBroker
import de.professional_webworkx.crm.domain.Person;
import java.util.List;


public interface IDateBroker {

    public abstract void saveOrUpdate(Person person);
    public abstract List<Person> getAllPersons();
    public abstract Person getPersonById(int id);
    public abstract Person getPersonByEmail(String email);
}
DataBroker - not every method is implemented... 
import de.professional_webworkx.crm.domain.Person;
import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.Persistence;

/**
 *
 * @author Patrick Ott <[e-mail]>
 * @version 1.0
 */
public class DataBroker implements IDateBroker {

    private EntityManager em;

    public DataBroker() {
        em = Persistence.createEntityManagerFactory("CRMPU").createEntityManager();
    }



    @Override
    public void saveOrUpdate(Person person) {
        em.getTransaction().begin();
        em.merge(person);
        em.getTransaction().commit();
    }

    @Override
    public List<Person> getAllPersons() {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public Person getPersonById(int id) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }

    @Override
    public Person getPersonByEmail(String email) {
        throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
    }


}
IPersonService Interface
import de.professional_webworkx.crm.domain.Person;
import java.util.List;


public interface IPersonService {

    void saveOrUpdate(Person person);
    List<Person> getAllPersons();
    Person getPersonById(int id);
    Person getPersonByEmail(String email);
}
PersonService
import de.professional_webworkx.crm.databroker.DataBroker;
import de.professional_webworkx.crm.databroker.IDateBroker;
import de.professional_webworkx.crm.domain.Person;
import java.util.List;


public class PersonService implements IPersonService {

    private IDateBroker broker;

    public PersonService() {
        broker = new DataBroker();
    }

    @Override
    public void saveOrUpdate(Person person) {
        broker.saveOrUpdate(person);
    }

    @Override
    public List<Person> getAllPersons() {
        return broker.getAllPersons();
    }

    @Override
    public Person getPersonById(int id) {
        return broker.getPersonById(id);
    }

    @Override
    public Person getPersonByEmail(String email) {
        return broker.getPersonByEmail(email);
    }
}
Our Domain class Person
import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;


@Entity
@Table(name = "person")
public class Person implements Serializable {

    private long id;
    private String firstName;
    private String lastName;
    private String eMail;

    public Person() {
    }

    public Person(String firstName, String lastName, String eMail) {
        this.firstName = firstName;
        this.lastName = lastName;
        this.eMail = eMail;
    }


    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    public long getId() {
        return id;
    }


    public void setId(long id) {
        this.id = id;
    }


    @Size(min = 2, max = 255, message = "Enter between 2 and 255 characters!")
    @Column(name = "firstname")
    @NotNull
    public String getFirstName() {
        return firstName;
    }


    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }


    @Column(name = "lastname")
    @NotNull
    public String getLastName() {
        return lastName;
    }


    public void setLastName(String lastName) {
        this.lastName = lastName;
    }


    @NotNull
    public String geteMail() {
        return eMail;
    }


    public void seteMail(String eMail) {
        this.eMail = eMail;
    }


}
The FXMLController class
import de.professional_webworkx.crm.business.IPersonService;
import de.professional_webworkx.crm.business.PersonService;
import de.professional_webworkx.crm.domain.Person;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.Label;

public class FXMLController implements Initializable {

    private IPersonService service;

    @FXML
    private Label label;

    @FXML
    private void handleButtonAction(ActionEvent event) {
        Person p = new Person("Demo", "User", "[e-mail]");
        service.saveOrUpdate(p);
    }

    @Override
    public void initialize(URL url, ResourceBundle rb) {
        // get an instance of PersonService
        service = new PersonService();

    }    
}
And last but not least the MainApp to start the Application.
import javafx.application.Application;
import static javafx.application.Application.launch;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;


public class MainApp extends Application {

    @Override
    public void start(Stage stage) throws Exception {
        Parent root = FXMLLoader.load(getClass().getResource("/fxml/Scene.fxml"));

        Scene scene = new Scene(root);
        scene.getStylesheets().add("/styles/Styles.css");

        stage.setTitle("JavaFX and Maven");
        stage.setScene(scene);
        stage.show();
    }


    public static void main(String[] args) {
        launch(args);
    }

}
This is a standard Maven JavaFX Project created with Netbeans 8. If necessary i can upload the Sources to GitHub or something.. 

The Database Table will be created with the first commit, because i set up in the persistence.xml file, that Schema Generation as you can see from the file
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
  <persistence-unit name="CRMPU" transaction-type="RESOURCE_LOCAL">
    <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
    <class>de.professional_webworkx.crm.domain.Person</class>
    <properties>
      <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:3306/exampleDb?zeroDateTimeBehavior=convertToNull"/>
      <property name="javax.persistence.jdbc.user" value="user"/>
      <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver"/>
      <property name="javax.persistence.jdbc.password" value="pass"/>
      <property name="javax.persistence.schema-generation.database.action" value="create"/>
    </properties>
  </persistence-unit>
</persistence>
So i hope this will help you to create your project.

Patrick

                        
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