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JEAP 6 - Clustered EJB3

本來是想在上一篇的ejb寫個同場加映,但是剛好出差北京,
想當然爾,因為當局嚴密的監控下,所有的部落格都無法登入。
只有回到台灣才能把這篇寫上去了!
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在閱讀這篇文章前,請先

A. 學會建立JBoss EAP 的 Cluster, Standalone or Domain 都可以. (請參考先前的文章)
B. 學會寫EJB (請看上次的 EJB 建立 Stateless session bean)

因為上次是寫Stateless, 那我們這次就寫Stateful Session Bean囉!

1. 請參考上次建立EJB 的方法,唯一的不同,就是這次建立的時候建的是Stateful. 然後建立完畢後,請在最上方加上@Clustered 的 annotation.



2. 啟動Cluster 的兩個JBoss EAP 6 Server, 把兩個EAR 檔案部署上去,這次我把其中一台的port 全部offset 成都加100.




3. 建立EJB Client, 這次換個不同的方式讀取設定檔,請在Client 的專案中,建立一個resource 的 檔案夾,建立jboss-ejb-client.properties. 這裡就是告訴我們的Client 有哪些EJB 的來源是可以去抓的。
package redhat.remote;

import java.util.Hashtable;

import javax.naming.Context;
import javax.naming.InitialContext;

import redhat.remotebeans.MyStatusBeanRemote;

public class EJBClient {
 
 public static void main(String ar[]) throws Exception{
        Context context=null;
        try{
         final Hashtable jndiProperties = new Hashtable();
            jndiProperties.put(Context.URL_PKG_PREFIXES, "org.jboss.ejb.client.naming");
            context = new InitialContext(jndiProperties);
          
        }catch (Exception e) {
              e.printStackTrace();
        }
       
       
        MyStatusBeanRemote remote=(MyStatusBeanRemote)context.lookup("ejb:MyEJBProjectEAR/MyEJBProject/MyStatusBean!redhat.remotebeans.MyStatusBeanRemote?stateful");
        System.out.println("1."+remote.getState());
        remote.updateState("Christina");
        System.out.println("2."+remote.getState()); 
       
     }

}


endpoint.name=client-endpoint
java.naming.factory.url.pkgs=org.jboss.ejb.client.naming
remote.clusters=ejb
remote.connectionprovider.create.options.org.xnio.Options.SSL_ENABLED=false
remote.connections=default,default1

remote.connection.default.host=localhost
remote.connection.default.port = 4447
remote.connection.default.connect.options.org.xnio.Options.SASL_POLICY_NOANONYMOUS=false
remote.connection.default1.host=localhost
remote.connection.default1.port = 4547
remote.connection.default1.connect.options.org.xnio.Options.SASL_POLICY_NOANONYMOUS=false

4. 執行 EJB Client, 可以看見他有成功地抓到兩個不同的EJB 來源。並且完成呼叫拉!




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這個題目很多人叫我寫,可是這題目好大,這分明就是整死我咩~
所以我會分幾段慢慢寫。

JBoss 的 SubsystemDatasource WebWeb Service EJB Hibernate JMSJCAJVM 調校OS (作業系統)

先來看一下 DataSource Subsystem, DataSource 的部分主要是針對Connection Pool 做調校。

通常,程式都會需要跟資料庫界接,電腦在本機,尤其是在記憶體的運算很快,但是一旦要外部的資源連接,就是會非常的耗資源。所以現在的應用程式伺服器都會有個Pool 放一些先連接好的 資料庫connection,當程式有需要的時候就可以馬上提供,而不用花那些多餘的資源去連接資料庫。

這就是為什麼要針對Connection Pool 去做調校。

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min-pool-size 

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max-pool-size 

Connection Pool 最多可以開啓的 connection 數量

prefill

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