ejb-jpa

最新推荐文章于 2021-12-01 21:46:51 发布

原创最新推荐文章于 2021-12-01 21:46:51 发布 · 118 阅读

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#EJB #JPA #MySQL #Hibernate #JBoss

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本文介绍了一个基于EJB的应用实例，包括实体对象定义、实体管理接口及其实现，并详细展示了如何通过客户端调用EJB服务，以及JBoss数据源配置。

一ejb 服务端基于ejb容器，客户端src下需要配置jndi配置文件

*实体对象

@Entity
public class Person implements Serializable {
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	@Id
	@GeneratedValue
	private int id;
	private String name;
	
}

*实体管理接口

import java.util.List;

public interface PersonManager {
	public void addPerson(Person person);
	public Person getPerson(int id);
	public Person getPerson2(int id);
	public List<Person> getPersons();
	public void updatePerson(Person person);
	public void deletePerson(int id);
	
	
}

*实体管理的实现

@Stateless
@Remote
@Local
public class PersonImpl implements PersonManager {
	@PersistenceContext(unitName="test")
	private EntityManager entityManager;
	public void addPerson(Person person) {
		entityManager.persist(person);
		//throw new RuntimeException("ddddddddddd");
	}
	public Person getPerson(int id) {
		//相当于hibernate中的load，是懒加载的
		Person p=entityManager.getReference(Person.class, id);
		System.out.println(p.getName());
		return p;
	}
	
	public Person getPerson2(int id){
		//相当于hibernate中的get
		Person p=entityManager.find(Person.class, id);
		return p;
	}
	
	public List<Person> getPersons(){
		return entityManager.createQuery(" from Person").getResultList();
	}
	
	public void updatePerson(Person person){
		entityManager.merge(person);
		
	}
	
	public void deletePerson(int id){
		
		entityManager.remove(getPerson(id));
	}
	
}

persistence.xml的配置文件

<?xml version="1.0" encoding="UTF-8"?>
<persistence 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" version="1.0">
    
	<persistence-unit name="test" transaction-type="JTA">
  		<jta-data-source>java:/MySqlDS</jta-data-source>
  			<properties>
  			<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
  			<property name="hibernate.show_sql" value="true"/>
  			<property name="hibernate.hbm2ddl.auto" value="update"/>
  		</properties>
	</persistence-unit>
  
</persistence>

二客户端

public class Client {

	/**
	 * @param args
	 */
	public static void main(String[] args) throws Exception {
		InitialContext context =new InitialContext();
		//UserTransaction  um=(UserTransaction )context.lookup("UserTransaction");
		//um.begin();
		PersonManager pm=(PersonManager)context.lookup("PersonImpl/remote");
		
		
//		Person p=new Person();
//		p.setName("www");
//		pm.addPerson(p);
		
		//Person p=pm.getPerson(5);
		//System.out.println(p.getName());
		
		
//		Person p=pm.getPerson2(5);
//		System.out.println(p.getName());
		
		//System.out.println(pm.getPersons().size());
		//um.commit();
		
//		Person p=new Person();
//		p.setId(5);
//		p.setName("xxxxxxxxxxxxx");
//		
//		pm.updatePerson(p);
		
	//	pm.deletePerson(5);
	}

}

三 jboss 数据源的配置

jboss 安装目录D:\jboss-4.0.5.GA\server\default\deploy 下放入

mysql-ds.xml

<?xml version="1.0" encoding="UTF-8"?>

<!-- $Id: mysql-ds.xml 41016 2006-02-07 14:23:00Z acoliver $ -->
<!--  Datasource config for MySQL using 3.0.9 available from:
http://www.mysql.com/downloads/api-jdbc-stable.html
-->

<datasources>
  <local-tx-datasource>
    <jndi-name>MySqlDS</jndi-name>
    <connection-url>jdbc:mysql://localhost:3306/ejb</connection-url>
    <driver-class>com.mysql.jdbc.Driver</driver-class>
    <user-name>root</user-name>
    <password>bjsxt</password>
    <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLExceptionSorter</exception-sorter-class-name>
    <!-- should only be used on drivers after 3.22.1 with "ping" support
    <valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLValidConnectionChecker</valid-connection-checker-class-name>
    -->
    <!-- sql to call when connection is created
    <new-connection-sql>some arbitrary sql</new-connection-sql>
      -->
    <!-- sql to call on an existing pooled connection when it is obtained from pool - MySQLValidConnectionChecker is preferred for newer drivers
    <check-valid-connection-sql>some arbitrary sql</check-valid-connection-sql>
      -->

    <!-- corresponding type-mapping in the standardjbosscmp-jdbc.xml (optional) -->
    <metadata>
       <type-mapping>mySQL</type-mapping>
    </metadata>
  </local-tx-datasource>
</datasources>