EJB3简单Demo
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2024-02-22 23:32:10
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开发工具及J2EE服务器:MyEclipse8.6 +Jboss 5.0
首先新建一个EJB项目,然后引用EJB所需的JAR包(%JBOSS_HOME%/client 下所有JAR包);
OK,下面开始开发:
package com.ejb.inter;
import javax.ejb.Remote;
/*标注为远程接口*/
@Remote
public interface HelloWord {
public String sayHello(String str);
}
package com.ejb.session;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.annotation.Resource;
import javax.ejb.Remote;
import javax.ejb.Stateless;
import javax.sql.DataSource;
import com.ejb.inter.HelloWord;
/**
* 查找数据源成功,能执行SQL
*
*/
@Stateless
@Remote({HelloWord.class})
public class HelloWordImpl implements HelloWord {
@Resource(mappedName="java:/MySqlDS") // @Resource 注释来注入来自JNDI 的任何资源。
DataSource ds;
public String sayHello(String str) {
try {
Connection con = ds.getConnection();
PreparedStatement ps = con.prepareStatement("select * from Stu_Info");
ResultSet set = ps.executeQuery();
while(set.next()){
System.out.println(set.getInt("stu_id")+"--"+set.getString("stu_name"));
}
set.close();
ps.close();
con.close();
System.out.println("--------------");
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return str+"欢迎使用EJB";
}
}
package com.ejb.test;
import java.util.Hashtable;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.rmi.PortableRemoteObject;
import com.ejb.inter.HelloWord;
public class TestClient {
/**
* @param args
*/
private static Context context;
public static void main(String[] args) {
// TODO Auto-generated method stub
try {
Context ctx =getInitialContext();
Object obj = ctx.lookup("HelloWordImpl/remote");
HelloWord hwImpl= (HelloWord)PortableRemoteObject.narrow(obj, HelloWord.class);
System.out.println(hwImpl.sayHello("中国"));
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private static Context getInitialContext()throws Exception{
if(context==null){
Hashtable ht =new Hashtable();
ht.put(Context.INITIAL_CONTEXT_FACTORY, "org.jnp.interfaces.NamingContextFactory");
ht.put(Context.URL_PKG_PREFIXES, "org.jboss.naming:org.jnp.interfaces");
ht.put(Context.PROVIDER_URL, "jnp://localhost:1099");
context = new InitialContext(ht);
}
return context;
}
}
开发完毕;
然后部署到JBOSS服务器上,运行TestClient.java 后台显示 "中国欢迎使用EJB"
注:在Jboss 后台管理jmx-console中 点击左边菜单Jboss.jca ,点击service=ManagerConnectionPool可以查看当前部署的数据源;
转载于:https://my.oschina.net/woter/blog/883527