/*

 *

 * Copyright 2000 Sun Microsystems, Inc. All Rights Reserved.

 * 

 * This software is the proprietary information of Sun Microsystems, Inc.  

 * Use is subject to license terms.

 * 

 */



import java.sql.*;

import javax.sql.*;

import java.util.*;

import javax.ejb.*;

import javax.naming.*;



public class StorageBinEJB implements EntityBean {



   private String storageBinId;

   private String widgetId;

   private int quantity;

   private EntityContext context;

   private Connection con;

   private String logicalDBName = "java:comp/env/jdbc/StorageBinDB";



   

   public String getWidgetId() {



      return widgetId;

   }



   public int getQuantity() {



      return quantity;

   }



   public String ejbCreate(String storageBinId, String widgetId, 

      int quantity)

      throws CreateException {



      try {

         insertRow(storageBinId, widgetId, quantity);

      } catch (Exception ex) {

          throw new EJBException("ejbCreate: " + 

             ex.getMessage());

      }



      this.storageBinId = storageBinId;

      this.widgetId = widgetId;

      this.quantity = quantity;



      return storageBinId;

    }



   public String ejbFindByPrimaryKey(String primaryKey) 

      throws FinderException {



      boolean result;



      try {

         result = selectByPrimaryKey(primaryKey);

       } catch (Exception ex) {

           throw new EJBException("ejbFindByPrimaryKey: " + 

              ex.getMessage());

       }



      if (result) {

         return primaryKey;

      }

      else {

         throw new ObjectNotFoundException

            ("Row for id " + primaryKey + " not found.");

      }

   }



   public String ejbFindByWidgetId(String widgetId) 

      throws FinderException {



      String storageBinId;



      try {

         storageBinId = selectByWidgetId(widgetId);

       } catch (Exception ex) {

           throw new EJBException("ejbFindByWidgetId: " + 

              ex.getMessage());

       }



      if (storageBinId == null) {

         throw new ObjectNotFoundException

            ("Row for widgetId " + widgetId + " not found.");

      }

      else {

         return storageBinId;

      }

   }



   public void ejbRemove() {



      try {

         deleteRow(storageBinId);

       } catch (Exception ex) {

           throw new EJBException("ejbRemove: " + 

              ex.getMessage());

       }

   } 



   public void setEntityContext(EntityContext context) {



      this.context = context;

      try {

         makeConnection();

      } catch (Exception ex) {

          throw new EJBException("Unable to connect to database. " +

             ex.getMessage());

      }

   }



   public void unsetEntityContext() {



      try {

         con.close();

      } catch (SQLException ex) {

          throw new EJBException("unsetEntityContext: " + ex.getMessage());

      }

   }



   public void ejbActivate() {



      storageBinId = (String)context.getPrimaryKey();

   }



   public void ejbPassivate() {



      storageBinId = null;

   }



   public void ejbLoad() {



      try {

         loadRow();

       } catch (Exception ex) {

           throw new EJBException("ejbLoad: " + 

              ex.getMessage());

       }

   }

   

   public void ejbStore() {



      try {

         storeRow();

       } catch (Exception ex) {

           throw new EJBException("ejbLoad: " + 

              ex.getMessage());

       }

   }





   public void ejbPostCreate(String storageBinId, String widgetId, 

      int quantity) { }





/*********************** Database Routines *************************/



   private void makeConnection() throws NamingException, SQLException {



      InitialContext ic = new InitialContext();

      DataSource ds = (DataSource) ic.lookup(logicalDBName);

      con =  ds.getConnection();

   }



   private void insertRow (String storageBinId, String widgetId, 

                           int quantity) throws SQLException {



      String insertStatement =

            "insert into storagebin values ( ? , ? , ? )";

      PreparedStatement prepStmt = 

            con.prepareStatement(insertStatement);



      prepStmt.setString(1, storageBinId);

      prepStmt.setString(2, widgetId);

      prepStmt.setInt(3, quantity);



      prepStmt.executeUpdate();

      prepStmt.close();

   }



   private void deleteRow(String storageBinId) throws SQLException {



      String deleteStatement =

            "delete from storagebin where storagebinid = ? ";

      PreparedStatement prepStmt =

            con.prepareStatement(deleteStatement);



      prepStmt.setString(1, storageBinId);

      prepStmt.executeUpdate();

      prepStmt.close();

   }



   private boolean selectByPrimaryKey(String primaryKey) 

      throws SQLException {



      String selectStatement =

            "select storagebinid " +

            "from storagebin where storagebinid = ? ";

      PreparedStatement prepStmt =

            con.prepareStatement(selectStatement);

      prepStmt.setString(1, primaryKey);



      ResultSet rs = prepStmt.executeQuery();

      boolean result = rs.next();

      prepStmt.close();

      return result;

   }





   private String selectByWidgetId(String widgetId) 

      throws SQLException {



      String storageBinId;



      String selectStatement =

            "select storagebinid " +

            "from storagebin where widgetid = ? ";

      PreparedStatement prepStmt =

            con.prepareStatement(selectStatement);

      prepStmt.setString(1, widgetId);



      ResultSet rs = prepStmt.executeQuery();



      if (rs.next()) {

         storageBinId = rs.getString(1);

      }

      else {

         storageBinId = null;

      }



      prepStmt.close();

      return storageBinId;

   }



   private void loadRow() throws SQLException {



      String selectStatement =

            "select widgetId, quantity " +

            "from storagebin where storagebinid = ? ";

      PreparedStatement prepStmt = 

            con.prepareStatement(selectStatement);



      prepStmt.setString(1, this.storageBinId);



      ResultSet rs = prepStmt.executeQuery();



      if (rs.next()) {

         this.widgetId = rs.getString(1);

         this.quantity = rs.getInt(2);

         prepStmt.close();

      }

      else {

         prepStmt.close();

         throw new NoSuchEntityException("Row for storageBinId " + storageBinId +

            " not found in database.");

      }

   }





   private void storeRow() throws SQLException {



      String updateStatement =

            "update storagebin set widgetId =  ? , " +

            "quantity = ? " +

            "where storagebinid = ?";

      PreparedStatement prepStmt = 

            con.prepareStatement(updateStatement);



      prepStmt.setString(1, widgetId);

      prepStmt.setInt(2, quantity);

      prepStmt.setString(3, storageBinId);

      int rowCount = prepStmt.executeUpdate();

      prepStmt.close();



      if (rowCount == 0) {

         throw new EJBException("Storing row for storageBinId " + 

            storageBinId + " failed.");

      }

   }



} // StorageBinEJB