carttestclient.java

主要是对EJB的提供的组件功能进行了介绍。还包括了案例~ 里面提供EJB ppt 会话Bean教案例子 实体Bean教案例子 实体EJB关系教案例子 CMP教案.ppt 消息驱动Bean教

package cartproject;

import javax.naming.*;
import java.util.Properties;
import javax.rmi.PortableRemoteObject;

public class cartTestClient extends Object {
  private static final String ERROR_NULL_REMOTE = "Remote interface reference is null.  It must be created by calling one of the Home interface methods first.";
  private static final int MAX_OUTPUT_LINE_LENGTH = 100;
  private boolean logging = true;
  private cartHome cartHomeObject = null;
  private cart cartObject = null;

  //Construct the EJB test client
  public cartTestClient() {
    initialize();
  }

  public void initialize() {
    long startTime = 0;
    if (logging) {
      log("Initializing bean access.");
      startTime = System.currentTimeMillis();
    }

    try {
      //get naming context
      Context context = getInitialContext();

      //look up jndi name
      Object ref = context.lookup("cart");
      //look up jndi name and cast to Home interface
      cartHomeObject = (cartHome) PortableRemoteObject.narrow(ref, cartHome.class);
      if (logging) {
        long endTime = System.currentTimeMillis();
        log("Succeeded initializing local bean access through Local Home interface.");
        log("Execution time: " + (endTime - startTime) + " ms.");
      }
    }
    catch(Exception e) {
      if (logging) {
        log("Failed initializing bean access.");
      }
      e.printStackTrace();
    }
  }

  private Context getInitialContext() throws Exception {
    String url = "t3://zhaoqiang:7001";
    String user = null;
    String password = null;
    Properties properties = null;
    try {
      properties = new Properties();
      properties.put(Context.INITIAL_CONTEXT_FACTORY, "weblogic.jndi.WLInitialContextFactory");
      properties.put(Context.PROVIDER_URL, url);
      if (user != null) {
        properties.put(Context.SECURITY_PRINCIPAL, user);
        properties.put(Context.SECURITY_CREDENTIALS, password == null ? "" : password);
      }

      return new InitialContext(properties);
    }
    catch(Exception e) {
      log("Unable to connect to WebLogic server at " + url);
      log("Please make sure that the server is running.");
      throw e;
    }
  }

  //----------------------------------------------------------------------------
  // Methods that use Home interface methods to generate a Remote interface reference
  //----------------------------------------------------------------------------

  public cart create(String _cardHolderName, String _creditCardNumber) {
    long startTime = 0;
    if (logging) {
      log("Calling create(" + _cardHolderName + ", " + _creditCardNumber + ")");
      startTime = System.currentTimeMillis();
    }
    try {
      cartObject = cartHomeObject.create(_cardHolderName, _creditCardNumber);
      if (logging) {
        long endTime = System.currentTimeMillis();
        log("Succeeded: create(" + _cardHolderName + ", " + _creditCardNumber + ")");
        log("Execution time: " + (endTime - startTime) + " ms.");
      }
    }
    catch(Exception e) {
      if (logging) {
        log("Failed: create(" + _cardHolderName + ", " + _creditCardNumber + ")");
      }
      e.printStackTrace();
    }

    if (logging) {
      log("Return value from create(" + _cardHolderName + ", " + _creditCardNumber + "): " + cartObject + ".");
    }
    return cartObject;
  }

  //----------------------------------------------------------------------------
  // Methods that use Remote interface methods to access data through the bean
  //----------------------------------------------------------------------------

  public void addItem(Item item) {
    if (cartObject == null) {
      System.out.println("Error in addItem(): " + ERROR_NULL_REMOTE);
      return ;
    }

    long startTime = 0;
    if (logging) {
      log("Calling addItem(" + item + ")");
      startTime = System.currentTimeMillis();
    }

    try {
      cartObject.addItem(item);
      if (logging) {
        long endTime = System.currentTimeMillis();
        log("Succeeded: addItem(" + item + ")");
        log("Execution time: " + (endTime - startTime) + " ms.");
      }
    }
    catch(Exception e) {
      if (logging) {
        log("Failed: addItem(" + item + ")");
      }
      e.printStackTrace();
    }
  }

  public void removeItem(Item item) {
    if (cartObject == null) {
      System.out.println("Error in removeItem(): " + ERROR_NULL_REMOTE);
      return ;
    }

    long startTime = 0;
    if (logging) {
      log("Calling removeItem(" + item + ")");
      startTime = System.currentTimeMillis();
    }

    try {
      cartObject.removeItem(item);
      if (logging) {
        long endTime = System.currentTimeMillis();
        log("Succeeded: removeItem(" + item + ")");
        log("Execution time: " + (endTime - startTime) + " ms.");
      }
    }
    catch(Exception e) {
      if (logging) {
        log("Failed: removeItem(" + item + ")");
      }
      e.printStackTrace();
    }
  }

  public float getTotalPrice() {
    float returnValue = 0f;

    if (cartObject == null) {
      System.out.println("Error in getTotalPrice(): " + ERROR_NULL_REMOTE);
      return returnValue;
    }

    long startTime = 0;
    if (logging) {
      log("Calling getTotalPrice()");
      startTime = System.currentTimeMillis();
    }

    try {
      returnValue = cartObject.getTotalPrice();
      if (logging) {
        long endTime = System.currentTimeMillis();
        log("Succeeded: getTotalPrice()");
        log("Execution time: " + (endTime - startTime) + " ms.");
      }
    }
    catch(Exception e) {
      if (logging) {
        log("Failed: getTotalPrice()");
      }
      e.printStackTrace();
    }

    if (logging) {
      log("Return value from getTotalPrice(): " + returnValue + ".");
    }
    return returnValue;
  }

  public void purchase() {
    if (cartObject == null) {
      System.out.println("Error in purchase(): " + ERROR_NULL_REMOTE);
      return ;
    }

    long startTime = 0;
    if (logging) {
      log("Calling purchase()");
      startTime = System.currentTimeMillis();
    }

    try {
      cartObject.purchase();
      if (logging) {
        long endTime = System.currentTimeMillis();
        log("Succeeded: purchase()");
        log("Execution time: " + (endTime - startTime) + " ms.");
      }
    }
    catch(Exception e) {
      if (logging) {
        log("Failed: purchase()");
      }
      e.printStackTrace();
    }
  }

  public void executeRemoteCallsWithDefaultArguments() {
    if (cartObject == null) {
      System.out.println("Error in executeRemoteCallsWithDefaultArguments(): " + ERROR_NULL_REMOTE);
      return ;
    }
    addItem(null);
    removeItem(null);
    getTotalPrice();
    purchase();
  }

  //----------------------------------------------------------------------------
  // Utility Methods
  //----------------------------------------------------------------------------

  private void log(String message) {
    if (message == null) {
      System.out.println("-- null");
      return ;
    }
    if (message.length() > MAX_OUTPUT_LINE_LENGTH) {
      System.out.println("-- " + message.substring(0, MAX_OUTPUT_LINE_LENGTH) + " ...");
    }
    else {
      System.out.println("-- " + message);
    }
  }
  //Main method

  public static void main(String[] args) {
    cartTestClient client = new cartTestClient();
    String cardHolderName = "Jack B. Quick";
    String creditCardNumber = "1234-5678-9012-3456";

   client.create(cardHolderName, creditCardNumber);
   Item knuthBook1 = new Item("The Art of VB.net", 49.95f);
   Item knuthBook2 = new Item("The Art of C#", 49.95f);
  client.addItem(knuthBook1);
  client.addItem(knuthBook2);
  client.removeItem(knuthBook2);
  client.purchase();

  }
}