package examples.ejb.basic.statelessSession;

import javax.ejb.*;
import javax.naming.*;
import java.rmi.RemoteException;
import java.util.*;

/**
 * This class illustrates using a stateless SessionBean:
 * <ul>
 * <li> It creates a trader, and perform repeated buying and selling of shares
 * <li> No persistence of state between calls to the SessionBean;
 *      the client must maintain state between calls
 * <li> How to search the JNDI tree for an appropriate container
 * <li> Application-defined exceptions
 * </ul>
 *
 * @author Copyright (c) 1998 by WebLogic, Inc. All Rights Reserved.
 * @author Copyright (c) 1998-1999 by BEA WebXpress. All Rights Reserved.
 */

public class Client {
  static String url       = "t3://localhost:7001";
  static String user      = null;
  static String password  = null;

  /**
   * Runs this example from the command line. Example:
   * <p>
   * <tt>java examples.ejb.basic.statelessSession.Client "t3://localhost:7001" scott tiger</tt>
   * <p>
   * The parameters are optional, but if any are supplied,
   * they are interpreted in this order:
   * <p>
   * @param url               URL such as "t3://localhost:7001" of Server
   * @param user              User name, default null
   * @param password          User password, default null
   */
  public static void main(String[] args) {
    System.out.println("\nBeginning statelessSession.Client...\n");

    // Parse the argument list 
    if ((args == null) || (args.length == 0)) {} 
      else
    for (int i = 0; i < args.length; i++) {
      switch(i) {
        case 0:
          url = args[i];
          break;
        case 1:
          user = args[i];
          break;
        case 2:
          password = args[i];
          break;
        default:
      }
    }

    String customerName = "Erin"; 
    try {
      // Create a trader object, who'll later help us execute trades
      Context ctx          = getInitialContext();
      TraderHome brokerage = (TraderHome) ctx.lookup("statelessSession.TraderHome");

      // Unlike the statefulSession example,
      // we don't give this trader a name
      System.out.println("Creating trader\n");
      Trader trader = brokerage.create();

      String stockName;
      int    numberOfShares;

      // Unlike the statefulSession example,
      // we have to keep track of the balance over the
      // life of our use of the session bean
      double cashBalance = 0.0;

      for (int i = 1 ; i <= 5; i++) {
        System.out.println("Start of Transaction " + i + " for " + customerName);

        // Buying
        stockName      = "WEBL";
        numberOfShares = 100 * i;
        System.out.println("Buying " + numberOfShares + " of " + stockName);
        TradeResult tr = trader.buy(customerName, stockName, numberOfShares);
        System.out.println("...Bought " + tr.numberTraded + " at $" + 
                           tr.priceSoldAt);
        // Keep track of the change in the Cash Account
        cashBalance = cashBalance - (tr.numberTraded * tr.priceSoldAt);

        // Selling
        stockName      = "INTL";
        numberOfShares = 100 * (i+1);
        System.out.println("Selling " + numberOfShares + " of " + stockName);
        tr = trader.sell(customerName, stockName, numberOfShares);
        System.out.println("...Sold " + tr.numberTraded + " at $" + 
                           tr.priceSoldAt);
        // Keep track of the change in the Cash Account
        cashBalance = cashBalance + (tr.numberTraded * tr.priceSoldAt);

        // Print change in Cash Account
        System.out.println("Change in Cash Account: $" + cashBalance);

        System.out.println("End of Transaction " + i + "\n");
      }
      System.out.println("Change in Cash Account: $" + cashBalance + "\n");
      System.out.println("Removing trader");
      trader.remove();
    }
    catch (ProcessingErrorException pe) {
      System.out.println("Processing Error: " + pe);
    } 
    catch (Exception e) {
      System.out.println(":::::::::::::: Error :::::::::::::::::");
      e.printStackTrace();
    }
    System.out.println("\nEnd statelessSession.Client...\n");
  }
 
  /**
   * Gets an initial context.
   *
   * @return                  Context
   * @exception               java.lang.Exception if there is
   *                          an error in getting a Context
   */
  static public Context getInitialContext() throws Exception {
    Hashtable h = new Hashtable();
    h.put(Context.INITIAL_CONTEXT_FACTORY,
        "weblogic.jndi.WLInitialContextFactory");
    h.put(Context.PROVIDER_URL, url);
    if (user != null) {
      System.out.println ("user: " + user);
      h.put(Context.SECURITY_PRINCIPAL, user);
      if (password == null) 
      password = "";
      h.put(Context.SECURITY_CREDENTIALS, password);
    } 
    return new InitialContext(h);
  }
}