package edu.rice.rubis.beans; import java.rmi.RemoteException; import javax.ejb.MessageDrivenBean; import javax.ejb.MessageDrivenContext; import javax.ejb.EJBException; import javax.jms.*; import javax.naming.Context; import javax.naming.InitialContext; import javax.rmi.PortableRemoteObject; import javax.sql.DataSource; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.io.Serializable; /** * This is a stateless session bean used to get the information to build the html form * used to put a comment on a user. * @author Emmanuel Cecchet and Julie Marguerite * @version 1.1 */ public class MDB_PutComment implements MessageDrivenBean, MessageListener { private DataSource dataSource; private MessageDrivenContext messageDrivenContext; private TopicConnectionFactory connectionFactory; private TopicConnection connection; private Topic topic; private TopicSession session; private TopicPublisher replier; private Context initialContext = null; public MDB_PutComment() { } public void onMessage(Message message) { try { MapMessage request = (MapMessage)message; String correlationID = request.getJMSCorrelationID(); int itemId = request.getInt("itemId"); int toId = request.getInt("toId"); String username = request.getString("username"); String password = request.getString("password"); // Retrieve the connection factory connectionFactory = (TopicConnectionFactory) initialContext.lookup(BeanConfig.TopicConnectionFactoryName); // get the post comment form String html = getCommentForm(itemId, toId, username, password); // send the reply TemporaryTopic temporaryTopic = (TemporaryTopic) request.getJMSReplyTo(); if (temporaryTopic != null) { // create a connection connection = connectionFactory.createTopicConnection(); // create a session: no transaction, auto ack session = connection.createTopicSession(false, Session.AUTO_ACKNOWLEDGE); TextMessage reply = session.createTextMessage(); reply.setJMSCorrelationID(correlationID); reply.setText(html); replier = session.createPublisher(null); // unidentified publisher connection.start(); replier.publish(temporaryTopic, reply); replier.close(); session.close(); connection.stop(); connection.close(); } } catch (Exception e) { throw new EJBException("Message traitment failed for MDB_PutComment: " +e); } } /** * Authenticate the user and get the information to build the html form. * * @return a string in html format * @since 1.1 */ public String getCommentForm(int itemId, int toId, String username, String password) throws RemoteException { int userId = -1; StringBuffer html = new StringBuffer(); PreparedStatement stmt = null; ResultSet rs = null; Connection conn = null; // Authenticate the user who want to comment if ((username != null && !username.equals("")) || (password != null && !password.equals(""))) { TopicConnection authConnection; TopicSession authSession; Topic authTopic; try { // create a connection authConnection = connectionFactory.createTopicConnection(); // lookup the destination authTopic = (Topic) initialContext.lookup(BeanConfig.PrefixTopicName+"topicAuth"); // create a session authSession = authConnection.createTopicSession(false, Session.AUTO_ACKNOWLEDGE); // no transaction and auto ack } catch (Exception e) { throw new EJBException("Cannot connect to message bean MDB_Auth : " +e+"
"); } try { // create a requestor to receive the reply TopicRequestor requestor = new TopicRequestor(authSession, authTopic); // create a message MapMessage m = authSession.createMapMessage(); // set parameters m.setStringProperty("nickname", username); m.setStringProperty("password", password); m.setJMSCorrelationID("auth"); // send the message and receive the reply authConnection.start(); // allows message to be delivered (default is connection stopped) MapMessage authReply = (MapMessage)requestor.request(m); authConnection.stop(); // read the reply userId = authReply.getInt("userId"); // close connection and session requestor.close(); // also close the session authConnection.close(); } catch (Exception e) { throw new EJBException("user authentication failed: " +e+"
"); } if (userId == -1) { html.append(" You don't have an account on RUBiS!
You have to register first.
"); return html.toString(); } } // Try to find the user corresponding to the 'to' ID String toName=null, itemName=null; try { conn = dataSource.getConnection(); stmt = conn.prepareStatement("SELECT nickname FROM users WHERE id=?"); stmt.setInt(1, toId); rs = stmt.executeQuery(); if (rs.first()) toName = rs.getString("nickname"); stmt.close(); } catch (Exception e) { try { if (stmt != null) stmt.close(); if (conn != null) conn.close(); } catch (Exception ignore) { } throw new RemoteException("Failed to execute Query for user name: " +e); } try { stmt = conn.prepareStatement("SELECT name FROM items WHERE id=?"); stmt.setInt(1, itemId); rs = stmt.executeQuery(); if (rs.first()) itemName = rs.getString("name"); if (stmt != null) stmt.close(); if (conn != null) conn.close(); } catch (Exception e) { try { if (stmt != null) stmt.close(); if (conn != null) conn.close(); } catch (Exception ignore) { } throw new RemoteException("Failed to execute Query for item name: " +e); } try { html.append("

Give feedback about your experience with "+toName+"


\n"); html.append("
\n"); html.append("\n"); html.append("\n"); html.append("\n"); html.append("
\n"); html.append("
From"+username+"\n"); html.append("
To"+toName+"\n"); html.append("
About item"+itemName+"\n"); } catch (Exception e) { throw new RemoteException("Cannot build comment form: " +e); } return html.toString(); } // ======================== EJB related methods ============================ /** * Set the associated context. The container call this method * after the instance creation. * The enterprise Bean instance should store the reference to the context * object in an instance variable. * This method is called with no transaction context. * * @param MessageDrivenContext A MessageDrivenContext interface for the instance. * @throws EJBException Thrown by the method to indicate a failure caused by * a system-level error. */ public void setMessageDrivenContext(MessageDrivenContext ctx) { messageDrivenContext = ctx; if (dataSource == null) { // Finds DataSource from JNDI try { initialContext = new InitialContext(); dataSource = (DataSource)initialContext.lookup("java:comp/env/jdbc/rubis"); } catch (Exception e) { throw new EJBException("Cannot get JNDI InitialContext"); } } } /** * The Message driven bean must define an ejbCreate methods with no args. * */ public void ejbCreate() { } /** * A container invokes this method before it ends the life of the message-driven object. * This happens when a container decides to terminate the message-driven object. * * This method is called with no transaction context. * * @throws EJBException Thrown by the method to indicate a failure caused by * a system-level error. */ public void ejbRemove() {} }