2007.09.04
By BeanSoft@126.com
下载此视频: http://download.gro.clinux.org/beansoft/jboss_myeclipse_entity.swf 4.12 MB 08分31秒
下载源代码: http://download.gro.clinux.org/beansoft/MyEntityBean.zip 437KB
这是使用 MyEclipse 开发的一个运行成功的 JBoss 的 Entity Bean. 源代码可以导入 MyEclipse, 然后编译发布.
环境:
JDK 1.5
JBoss 4.2.1 GA
MyEclipse 5.5.1 GA
Derby
下载项目源码 MyEntityBean.zip
文件列表如下所示:
2007-09-05 15:33 429 .classpath
2007-09-05 15:29 <DIR> .myeclipse
2007-09-05 15:29 175 .mymetadata
2007-09-05 15:33 1,137 .project
2007-09-05 15:30 <DIR> .settings
2007-09-05 15:33 <DIR> classes
2007-09-05 16:13 390 client.txt
2007-09-05 16:12 102 create.sql
2007-09-05 16:14 891 derby-ds.xml
2007-09-05 16:12 465,668 derbyclient.jar
2007-09-05 15:33 <DIR> src
操作步骤:
首先当然是配置数据源了.
1. 先请把 derbyclient.jar 复制到 $JBOSS_HOME/server/default/lib/ 下, 然后重启 JBoss 服务器.
2. 在 MyEclipse 中启动 MyEclipse Derby 数据库服务器, 并创建一个测试表并插入一条数据:
createtable myuser (id intprimarykey, username varchar(20));
insert into myuser values(1, 'test');
3. 编写一个 DataSource 配置文件: derby-ds.xml (项目文件中已经附带), 并复制到目录 $JBOSS_HOME/server/default/deploy/ 下, 注意这些变量:
<jndi-name>DerbyDS</jndi-name> 和 <connection-url>jdbc:derby://localhost:1527/myeclipse;create=true</connection-url>
<!-- The driver class -->
<driver-class>org.apache.derby.jdbc.ClientDriver</driver-class>
<!-- The login and password -->
<user-name>app</user-name>
<password>app</password> 这几个一定要和你上一步建表时候所用的数据库连接的 URL, 用户名, 密码一致.
jndi-name 则是最后 EJB 所能访问到的数据源的地址.
文件完整内容示例:
<?xmlversion="1.0"encoding="UTF-8"?><!-- The Hypersonic embedded database JCA connection factory config --><!-- $Id: hsqldb-ds.xml 63175 2007-05-21 16:26:06Z rrajesh $ --><datasources><local-tx-datasource><!-- The jndi name of the DataSource, it is prefixed with java:/ --><!-- Datasources are not available outside the virtual machine --><jndi-name>DerbyDS</jndi-name><connection-url>jdbc:derby://localhost:1527/myeclipse;create=true</connection-url><!-- The driver class --><driver-class>org.apache.derby.jdbc.ClientDriver</driver-class><!-- The login and password --><user-name>app</user-name><password>app</password><!-- corresponding type-mapping in the standardjbosscmp-jdbc.xml --><metadata><type-mapping>Derby</type-mapping></metadata></local-tx-datasource></datasources>
至此, 数据源算是配置完毕. 你可以在 JBoss 的 JNDI View 中查看到这个 DerbyDS.
4. 导入项目 MyEntityBean 到 MyEclipse.
5. 将文件 $JBOSS_HOME/client/jbossall-client.jar 加入到项目的 Build Path(相当于 CLASSPATH) 中, 然后通过 MyEclipse 进行编译和部署. 部署后同样可以通过 JNDIView 来检查是否发布成功了 EJB.
6. 运行 TestMyEntityBean 来进行调用测试, 成功后可以在后台数据库看到插入的数据.
附 Bean 源码:
测试类:
import java.util.*;
import javax.naming.*;
publicclass TestMyEntityBean {
/** * @param args */publicstaticvoid main(String[] args) throws Exception {
// 手工初始化的过程
Hashtable properties = new Hashtable();
// 配置驱动程序, JBoss 特定的
properties.put(Context.INITIAL_CONTEXT_FACTORY,
"org.jnp.interfaces.NamingContextFactory");
// 配置 URL, JBoss 特定的
properties.put(Context.PROVIDER_URL, "jnp://localhost");
InitialContext ctx = new javax.naming.InitialContext(properties);
// 初始化, 相当于打开文件浏览器
entity.TestuserFacadeRemote remote = (entity.TestuserFacadeRemote)ctx.lookup("TestuserFacade/remote");
entity.Testuser user = new entity.Testuser();
user.setId(3);
user.setUsername("username3");
remote.save(user);
ctx.close();
}
}
Bean Remote 接口:
package entity;
import java.util.List;
import javax.ejb.Remote;
/** * Remote interface for TestuserFacade. * * @author MyEclipse Persistence Tools */
@Remote
publicinterface TestuserFacadeRemote {
publicvoid save(Testuser transientInstance);
publicvoid delete(Testuser persistentInstance);
public Testuser update(Testuser detachedInstance);
public Testuser findById(Integer id);
public List findByProperty(String propertyName, Object value);
}
Bean 类:
package entity;
import java.util.List;
import java.util.logging.Level;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
/** * Facade for entity Testuser. * * @see entity.Testuser * @author MyEclipse Persistence Tools */
@Stateless
publicclass TestuserFacade implements TestuserFacadeRemote {
@PersistenceContext
private EntityManager entityManager;
publicvoid save(Testuser transientInstance) {
// EntityManagerHelper.log("saving Testuser instance", Level.INFO, null);try {
entityManager.persist(transientInstance);
// EntityManagerHelper.log("save successful", Level.INFO, null);
} catch (RuntimeException re) {
// EntityManagerHelper.log("save failed", Level.SEVERE, re);throw re;
}
}
publicvoid delete(Testuser persistentInstance) {
// EntityManagerHelper.log("deleting Testuser instance", Level.INFO, null);try {
entityManager.remove(persistentInstance);
// EntityManagerHelper.log("delete successful", Level.INFO, null);
} catch (RuntimeException re) {
// EntityManagerHelper.log("delete failed", Level.SEVERE, re);throw re;
}
}
public Testuser update(Testuser detachedInstance) {
// EntityManagerHelper.log("updating Testuser instance", Level.INFO, null);try {
Testuser result = entityManager.merge(detachedInstance);
// EntityManagerHelper.log("update successful", Level.INFO, null);return result;
} catch (RuntimeException re) {
// EntityManagerHelper.log("update failed", Level.SEVERE, re);throw re;
}
}
public Testuser findById(Integer id) {
// EntityManagerHelper.log("finding Testuser instance with id: " + id,// Level.INFO, null);try {
Testuser instance = entityManager.find(Testuser.class, id);
return instance;
} catch (RuntimeException re) {
// EntityManagerHelper.log("find failed", Level.SEVERE, re);throw re;
}
}
@SuppressWarnings("unchecked")
public List<Testuser> findByProperty(String propertyName, Object value) {
// EntityManagerHelper.log("finding Testuser instance with property: "// + propertyName + ", value: " + value, Level.INFO, null);try {
String queryString = "select model from Testuser model where model."
+ propertyName + "= :propertyValue";
return entityManager.createQuery(queryString).setParameter(
"propertyValue", value).getResultList();
} catch (RuntimeException re) {
// EntityManagerHelper.log("find by property name failed",// Level.SEVERE, re);throw re;
}
}
@SuppressWarnings("unchecked")
public List<Testuser> findAll() {
// EntityManagerHelper.log("finding all Testuser instances", Level.INFO,// null);try {
String queryString = "select model from Testuser model";
return entityManager.createQuery(queryString).getResultList();
} catch (RuntimeException re) {
// EntityManagerHelper.log("find all failed", Level.SEVERE, re);throw re;
}
}
}
Entity 类:
package entity;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
/** * Testuser generated by MyEclipse Persistence Tools */
@Entity
@Table(name = "TESTUSER", schema = "APP", uniqueConstraints = {})
publicclass Testuser implements java.io.Serializable {
// Fields private Integer id;
private String username;
// Constructors /** default constructor */public Testuser() {
}
/** minimal constructor */public Testuser(Integer id) {
this.id = id;
}
/** full constructor */public Testuser(Integer id, String username) {
this.id = id;
this.username = username;
}
// Property accessors
@Id
@Column(name = "ID", unique = true, nullable = false, insertable = true, updatable = true)
public Integer getId() {
returnthis.id;
}
publicvoid setId(Integer id) {
this.id = id;
}
@Column(name = "USERNAME", unique = false, nullable = true, insertable = true, updatable = true, length = 20)
public String getUsername() {
returnthis.username;
}
publicvoid setUsername(String username) {
this.username = username;
}
}