customerwebimpl.java

来自「一个优秀的供应商管理系统」· Java 代码 · 共 50 行

package apusic.myshop.customer.web;



import java.rmi.RemoteException;
import apusic.myshop.control.GeneralFailureException;

import apusic.myshop.customer.model.CustomerModel;
import apusic.myshop.control.web.ModelUpdateListener;
import apusic.myshop.control.web.ModelManager;
import apusic.myshop.customer.ejb.Customer;
import apusic.myshop.util.JNDINames;

//观察者

public class CustomerWebImpl extends CustomerModel implements ModelUpdateListener {

//主题
  private ModelManager mm;
//顾客实体
  private Customer custEjb;
//构造函数初始化
  public CustomerWebImpl() {
    // This bean should created by the request processor
    System.out.println("CustomerWebImpl: This bean should not be instanciated from a JSP");
  }

//初始化观察者并添加到主题中
  public CustomerWebImpl(ModelManager mm) {

    super(null, null, null, null, null, null,
      null, null, null, null, null, null, null);
    this.mm = mm;
	  mm.addListener(JNDINames.CUSTOMER_EJBHOME, this);
  }

//观察者更新自己

  public void performUpdate() {
	  // Get data from the EJB
	  if (custEjb == null) {
      custEjb = mm.getCustomerEJB();
	  }
	  try {
      if (custEjb != null) copy(custEjb.getDetails());
	  } catch (RemoteException re) {
      throw new GeneralFailureException(re);
    }
  }
}