ejbhomefactory.java

来自「100多M的J2EE培训内容」· Java 代码 · 共 50 行

package com.borland.training.meetings.sessions;

import javax.naming.*;
import java.util.*;
import javax.ejb.*;
import com.borland.training.meetings.entities.*;
import com.borland.training.meetings.sessions.*;

public class EJBHomeFactory {

  private static EJBHomeFactory instance = null;
  private Context initialContext;
  private Map ejbHomes;

  private EJBHomeFactory() throws NamingException {
    initialContext = new InitialContext();
    ejbHomes = Collections.synchronizedMap(new HashMap());
  }

  public static EJBHomeFactory getInstance() throws NamingException {
    if(instance == null) {
      instance = new EJBHomeFactory();
    }
    return instance;
  }

  public EJBLocalHome lookupByLocalEJBReference(String ejbReferenceComponent)
    throws NamingException {

    java.lang.Object home = ejbHomes.get(ejbReferenceComponent);
    if(home == null) {
      home = initialContext.lookup("java:comp/env/ejb/" + ejbReferenceComponent);
      ejbHomes.put(ejbReferenceComponent, home);
    }
    return (EJBLocalHome) home;
  }

  public EJBHome lookupByRemoteEJBReference(String ejbReferenceComponent, Class homeClass)
    throws NamingException {

    java.lang.Object home = ejbHomes.get(ejbReferenceComponent);
    if(home == null) {
      java.lang.Object obj =
        initialContext.lookup("java:comp/env/ejb/" + ejbReferenceComponent);
      home = javax.rmi.PortableRemoteObject.narrow(obj, homeClass);
      ejbHomes.put(ejbReferenceComponent, home);
    }
    return (EJBHome) home;
  }
}