新建一个EJB3项目,在WETA-INF目录下新建persistence.xml文件,其中"hibernate.hbm2ddl.auto" value="create-drop",则不需要人工建立数据库表,会自动帮你建立。hibernate.dialect如果没写,也会提示出错。
persistence.xml
<?xml version="1.0" encoding="UTF-8"?>
<persistence>
<persistence-unit name="Ejb3">
<jta-data-source>java:/ejb3Example</jta-data-source>
<properties>
<property name="hibernate.hbm2ddl.auto"
value="create-drop"/>
<property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/>
</properties>
</persistence-unit>
</persistence>
建立entity bean:Book.java,这是一个普通POJO,里面使用JPA注释它是一个entity bean,在领域模型里,实体类继承Serializable接口实现序列化,有利于使用缓存。如果有提示@Table(name="book")
出错,找不到数据库表,不用管它,最后系统会自动建立数据库表,当然,自己手动建立一个也可。
Book.java
import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.SequenceGenerator;
import javax.persistence.Table;
import javax.persistence.TableGenerator;
@Entity
@Table(name="book")
@TableGenerator( name="book_id", table="primary_keys", pkColumnName="key", pkColumnValue="book",valueColumnName="value")
public class Book implements Serializable {
private static final long serialVersionUID = 1L;
private Integer id;
private String title;
private String author;
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
@Id
@GeneratedValue(strategy = GenerationType.AUTO, generator = "book_id")
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public Book() {
super();
}
public Book(Integer id, String title, String author) {
super();
this.id = id;
this.title = title;
this.author = author;
}
@Override
public String toString() {
// TODO Auto-generated method stub
return "Book: " + getId() + " Title " + getTitle() + " Author "
+ getAuthor();
}
}
建立一个session bean:BookTestBean.java,并添加本地和远程接口BookTestBeanLocal.java、BookTestBeanRemote.java
BookTestBean.java
import java.util.Iterator;
import java.util.List;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
@Stateless
public class BookTestBean implements BookTestBeanLocal, BookTestBeanRemote {
@PersistenceContext
EntityManager em;
public static final String RemoteJNDIName = BookTestBean.class.getSimpleName() +
"/remote";
public static final String LocalJNDIName = BookTestBean.class.getSimpleName() +
"/local";
public void test() {
Book book = new Book(null, "My first bean book", "Sebastian");
em.persist(book);
Book book2 = new Book(null, "another book", "Paul");
em.persist(book2);
Book book3 = new Book(null, "EJB 3 developer guide, comes soon",
"Sebastian");
em.persist(book3);
System.out.println("list some books");
List someBooks = em.createQuery("from Book b where b.author=:name")
.setParameter("name", "Sebastian").getResultList();
for (Iterator iter = someBooks.iterator(); iter.hasNext();)
{
Book element = (Book) iter.next();
System.out.println(element);
}
System.out.println("List all books");
List allBooks = em.createQuery("from Book").getResultList();
for (Iterator iter = allBooks.iterator(); iter.hasNext();)
{
Book element = (Book) iter.next();
System.out.println(element);
}
System.out.println("delete a book");
em.remove(book2);
System.out.println("List all books");
allBooks = em.createQuery("from Book").getResultList();
for (Iterator iter = allBooks.iterator(); iter.hasNext();)
{
Book element = (Book) iter.next();
System.out.println(element);
}
}
}
BookTestBeanLocal.java
import javax.ejb.Local;
@Local
public interface BookTestBeanLocal {
public void test();
}
BookTestBeanRemote.java
import javax.ejb.Remote;
@Remote
public interface BookTestBeanRemote {
public void test();
}
在%JBOSS_HOME%\server\default\deploy下新建文件EJB-DS.XML,相应的数据库写法,可在%JBOSS_HOME%\docs\examples\jca中找到。
EJB-DS.XML
<?xml version="1.0" encoding="UTF-8"?>
<datasources>
<local-tx-datasource>
<jndi-name>ejb3Example</jndi-name>
<connection-url>jdbc:mysql://localhost:3306/mysql</connection-url>
<driver-class>com.mysql.jdbc.Driver</driver-class>
<user-name>xx</user-name>
<password>xx</password>
<exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLExceptionSorter</exception-sorter-class-name>
<metadata>
<type-mapping>mySQL</type-mapping>
</metadata>
</local-tx-datasource>
</datasources>
这是所用到的包。
在JBOSS中部署成jar,查看是否部署成功。
编写测试客户端TestClient.java,并在META-INF下添加jndi.properies。
TestClient.java
import java.util.Properties;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
public class TestClient.java{
/**
* @param args
*/
public static void main(String[] args) {
Context context;
try
{
context = new InitialContext();
BookTestBeanRemote beanRemote = (BookTestBeanRemote) context.lookup(BookTestBean.RemoteJNDIName);
beanRemote.test();
} catch (NamingException e)
{
e.printStackTrace();
throw new RuntimeException(e);
}
}
}
jndi.properies
java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory
java.naming.factory.url.pkgs=org.jboss.naming:org.jnp.interfaces
java.naming.provider.url=localhost:1099
此时客户端测试只需要一个J2EE包和jbossall-client.jar便可。如果客户端与服务器端的包有冲突或版本不同,就会有stream classdesc serialVersionUID = 4582256576523491346, local class serialVersionUID = 3844706474734439975这样的序列化出错。
最后运行客户端测试。
posted on 2008-03-13 12:35
lzj520 阅读(522)
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