package examples.ejb.basic.statefulSession;

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

/**
 * This class demonstrates calling an statefulsession EJBean
 * using multiple colocated clients:
 * <ul>
 * <li> Each thread is a trader, and perform repeated buying and selling of shares
 * <li> Persistence of state between calls to the SessionBean;
 *      the client does not do anything to maintain state between calls
 * <li> How to search the JNDI tree for an appropriate container
 * <li> Application-defined exceptions
 * </ul>
 *
 * @author Copyright (c) 1998-1999 by BEA Systems, Inc. All Rights Reserved.
 */
public class MultiClient {

  static String    url                      = "t3://localhost:7001";
  static String    user                     = null;
  static String    password                 = null;
  static int       numTraders               = 10;
  static final int numTransactionsPerTrader = 10;

  /**
   * Runs this example from the command line. Example:
   * <p>
   * <tt>java examples.ejb.basic.statefulSession.MultiClient "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 statefulSession.MultiClient...\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 {
      MultiClientBigTrader[] traders = new MultiClientBigTrader[numTraders];

      Context    ctx       = getInitialContext();
      TraderHome brokerage = (TraderHome) ctx.lookup("statefulSession.TraderHome");

      for (int i = 0; i < numTraders; i++) {
        // Create a trader object, who'll later help us execute trades
        // Give this trader a name
        Trader trader = brokerage.create("Terry" + i);
        System.out.println("Creating trader " + trader.getTraderName() + "\n");
        traders[i] = new MultiClientBigTrader(i, trader, customerName);
        traders[i].start();
      }
      for (int i = 0; i < numTraders; i++) {
        try {
          traders[i].join(0);
        }
        catch (Exception e) {
          System.out.println(":::::::: Thread Join Error :::::::::::\n" + e);
        }
      }
    }
    catch (Exception e) {
      System.out.println(":::::::::::::: Error :::::::::::::::::");
      e.printStackTrace();
    }
    System.out.println("\nEnd statefulSession.MultiClient...\n");
  }

  /**
   * Parses an argument list for a url, user or password.
   *
   * @param args[]            String array of arguments
   */
  static void parseArgs(String args[]) {
    if ((args == null) || (args.length == 0)) 
      return;
    for (int i = 0; i < args.length; i++) {
      if (args[i].equals("-url")) 
        url = args[++i];
      else if (args[i].equals("-user")) 
        user = args[++i];
      else if (args[i].equals("-password")) 
        password = args[++i];
    }
  }
  
  /**
   * 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 {
    Properties p = new Properties();
    p.put(Context.INITIAL_CONTEXT_FACTORY,
          "weblogic.jndi.WLInitialContextFactory");
    p.put(Context.PROVIDER_URL, url);
    if (user != null) {
      System.out.println ("user: " + user);
      p.put(Context.SECURITY_PRINCIPAL, user);
      if (password == null) 
      password = "";
      p.put(Context.SECURITY_CREDENTIALS, password);
    } 
    return new InitialContext(p);
  }
}

/**
 * This class creates the MultiClientBigTrader threads used by
 * MultiClient.
 * 
 * @author                    Copyright (c) 1998-1999 by BEA Systems, Inc. All Rights Reserved.
 * @see                       MultiClient
 */
class MultiClientBigTrader extends Thread {

  int    id;
  Trader trader;
  String customer;

  /**
   * Creates a MultiClientBigTrader with an ID and
   * an account.
   *
   * @param id                  int ID
   * @param trader              Trader Trader
   * @param customer            String Customer
   * @see                       MultiClient#main
   */
  public MultiClientBigTrader(int id, Trader trader, String customer) {
    this.id       = id;
    this.trader   = trader;
    this.customer = customer;
  }

  /**
   * Runs a MultiClientBigTrader and makes it
   * conduct transactions for its account.
   * @see                       MultiClient#main
   */
  public void run() {
    try {
      String traderName = trader.getTraderName();
      for (int i = 0; i < MultiClient.numTransactionsPerTrader; i++) {
        System.out.println(traderName + ": Start of Transaction " + i + " for " + customer);
        String stockName;
        int    numberOfShares;

        // Buying
        stockName      = "WEBL";
        numberOfShares = 100 * i;
        System.out.println(traderName + ": Buying " + numberOfShares + " of " + stockName);
        TradeResult tr = trader.buy(customer, stockName, numberOfShares);
        System.out.println(traderName + ": Bought " + tr.numberTraded + " at $" + 
                           tr.priceSoldAt);
        // Selling
        stockName      = "INTL";
        numberOfShares = 100 * (i+1);
        System.out.println(traderName + ": Selling " + numberOfShares + " of " + stockName);
        tr = trader.sell(customer, stockName, numberOfShares);
        System.out.println(traderName + ": Sold " + tr.numberTraded + " at $" + 
                           tr.priceSoldAt);

        // Get change in Cash Account from EJBean
        System.out.println(traderName + ": Change in Cash Account: $" + trader.getBalance());

        System.out.println(traderName + ": End of Transaction " + i + "\n");
      }
      System.out.println(traderName + ": Change in Cash Account: $" + trader.getBalance() + "\n");
    } 
    catch (Exception e) {
      System.out.println("Aborting thread " + id + ": " + 
                         weblogic.utils.StackTraceUtils.throwable2StackTrace(e));
    }
  }
}