tradingclient.java

来自「100多M的J2EE培训内容」· Java 代码 · 共 96 行

package bible.rmi.example3;

import java.util.*;
import javax.naming.*;
import weblogic.rmi.*;

/**
 * Periodically enters orders to the remote server and remotely
 * receive updates of executions.
 */
public class TradingClient extends TimerTask
  implements Runnable, ExecutionAlert {

  /** orderNumber           */
  private static int orderNumber = 0;

  /**
   * notifyOfExecution
   * @param exec
   */
  public void notifyOfExecution(Execution exec) throws java.rmi.RemoteException {

    System.out.println("An order has been executed!");
    System.out.println("Time: " + new Date());
    System.out.println(exec + "\n");
  }

  /**
   * Places a stock order with the remote server.
   */
  public void run() {

    System.out.println("Client now placing an order... ");
    System.out.println(" Time: " + new Date() + "\n");

    InitialContext ctx = null;
    try {

      // Get the remote stub for the Price server via JNDI.
      ctx = Environment.getInitialContext();

      PriceServer server =
        (PriceServer) ctx.lookup(PriceServer.PRICESERVERNAME);

      // Get the list of securities managed by the server.
      String securities [] = server.getSecurities();

      // Create a new Order instance
      Order  order = new Order();
      Random rand  = new Random();

      // Increment the order number
      order.setNumber(++orderNumber);

      // Choose one of the available securities at random
      order.setSymbol(securities [rand.nextInt(securities.length)]);

      // Choose a random number of shares
      order.setShares(100 * (rand.nextInt(9) + 1));

      // Enter the order via a remote call to the server.
      // Pass the reference to ourselves so the server can call back.
      server.enterMarketOrder(order, this);
    } catch (Exception e) {
      e.printStackTrace();
    } finally {
      try {
        ctx.close();
      } catch (Exception e) {
        e.printStackTrace();
      }
    }
  }

  /**
   * Instantiates a client and puts it on a repeating timer.
   * @param args
   */
  public static void main(String[] args) {

    try {
      Timer         t      = new Timer();
      TradingClient client = new TradingClient();
      Context       ctx    = Environment.getInitialContext();
      ctx.bind("TradingClient", client);
      System.out
        .println("TradingClient was started and bound in the registry "
                 + "to the name TradingClient");
      t.schedule(client, 5000, 45000);
    } catch (Exception e) {
      e.printStackTrace();
      System.exit(1);
    }
  }
}