managerbean.java

一个java

package bookstore.ejb;

import bookstore.util.*;

import java.sql.*;
import javax.sql.*;
import java.util.*;
import javax.ejb.*;
import javax.naming.*;


public class ManagerBean implements EntityBean {
  java.lang.String managerID;
  java.lang.String name;
  java.lang.String password;

  private Connection con=null;
  EntityContext entityContext;
  /**************************business methods*****************************/
  public void setManagerID(java.lang.String managerID) {
    this.managerID = managerID;
  }
  public void setName(java.lang.String name) {
    this.name = name;
  }
  public void setPassword(java.lang.String password) {
    this.password = password;
  }
  public java.lang.String getManagerID() {
    return managerID;
  }
  public java.lang.String getName() {
    return name;
  }
  public java.lang.String getPassword() {
    return password;
  }


  public ManagerDetails getDetails()
     {
        System.out.println("managerBean getDetails");

        return new ManagerDetails (managerID,name ,password);
     }//getDetails

    /********************************ejb methods**************************/
    public java.lang.String ejbCreate(ManagerDetails managerValue) throws CreateException {
      System.out.println("managerBean ejbCreate");

          try
          {
            makeConnection();
            this.managerID=DBHelper.getNextManagerID(con);
          }catch(Exception ex)
          {
            throw new EJBException("ejbCreate: "+ex.getMessage());
          }

          this.name=managerValue.getName();
          this.password=managerValue.getPassword();

          try {
              insertRow();
          } catch (Exception ex) {
               throw new EJBException("ejbCreate: " +
                   ex.getMessage());
          }

          return managerID;

    }

    public void ejbPostCreate(ManagerDetails managerValue) throws CreateException {
      System.out.println("managerBean ejbPostCreate");
    }

    public java.util.Collection ejbFindByCondition(String condition) throws FinderException {
      System.out.println("managerBean ejbFindByCondition");

      Collection result;

      try {
             result = selectByCondition(condition);
         } catch (Exception ex) {
               throw new EJBException("ejbFindByCondition " +
                   ex.getMessage());
         }
         return result;

    }

    public void ejbRemove() throws RemoveException {
      System.out.println("managerBean ejbRemove");

      try {
              deleteRow(managerID);
           } catch (Exception ex) {
                throw new EJBException("ejbRemove: " +
                    ex.getMessage());
           }
    }//ejbRemove

    public java.lang.String ejbFindByPrimaryKey(java.lang.String primaryKey) throws FinderException {

           System.out.println("managerBean ejbFindByPrimaryKey");

           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 void ejbLoad() {

            System.out.println("managerBean ejbLoad");

            try {
                loadManager();
             } catch (Exception ex) {
                  throw new EJBException("ejbLoad: " +
                      ex.getMessage());
             }
        }//ejbLoad

        public void ejbStore()
        {

              System.out.println("managerBean ejbStore");

              try {
                  storeManager();
               } catch (Exception ex) {
                    throw new EJBException("ejbStore: " +
                        ex.getMessage());
               }
          }//ejbStore

    public void ejbActivate()
    {
          System.out.println("managerBean ejbActivate");
          //
          managerID = (String)entityContext.getPrimaryKey();
      }

      public void ejbPassivate()
      {
          System.out.println("managerBean ejbPassivate");

          managerID= null;
      }

    public void unsetEntityContext()
    {
      System.out.println("managerBean ussetEntiyContext");
      this.entityContext = null;
    }
    public void setEntityContext(EntityContext entityContext) {
      System.out.println("managerBean setEntiyContext");
      this.entityContext = entityContext;
    }

    /****************************util methods*******************************/
    private void makeConnection() {

          System.out.println("managerBean makeConnection in");
          try
             {
               InitialContext ic = new InitialContext();
               DataSource ds = (DataSource) ic.lookup("DBSource");
               con = ds.getConnection();
             }
             catch (Exception ex)
             {
               throw new EJBException("Unable to connect to database. " +
                                     ex.getMessage());
             }
          System.out.println("managerBean makeConnection out");
      } // makeConnection


      private void releaseConnection() {

          System.out.println("managerBean releaseConnection in");

          try {
              con.close();
          } catch (SQLException ex) {
               throw new EJBException("releaseConnection: " + ex.getMessage());
          }
          System.out.println("managerBean releaseConnection out");

      } // releaseConnection


      private void insertRow () throws SQLException {

          System.out.println("managerBean insertRow in");

          makeConnection();
          String insertStatement =
              "insert into manager values ( ? , ? , ? )";
          PreparedStatement prepStmt =
              con.prepareStatement(insertStatement);
          prepStmt.setString(1, managerID);
          prepStmt.setString(2, name);
          prepStmt.setString(3, password);

          prepStmt.executeUpdate();
          prepStmt.close();
          releaseConnection();
          System.out.println("managerBean insertRow out");
      }//insertRow

      private Collection selectByCondition(String condition) throws SQLException {

         System.out.println("managerBean selectByCondition in");

         makeConnection();
         String selectStatement =
                 "select managerID " +
                 "from manager where "+condition;
         System.out.println(selectStatement);
         Statement stmt=con.createStatement();
         ResultSet rs=stmt.executeQuery(selectStatement);

         ArrayList a = new ArrayList();
         while (rs.next())
         {
             a.add(rs.getString(1));
         }

         stmt.close();
         releaseConnection();
         System.out.println("managerBean selectByCondition out");
         return a;
     }//selectByCondition

     private boolean selectByPrimaryKey(String primaryKey) throws SQLException {
          //本函数主要目的还在于确保manager_id在数据库表中是存在的
          System.out.println("managerBean selectByPrimaryKey in");

          makeConnection();
          //a question here
          String selectStatement =
                  "select managerID " +
                  "from manager where managerID = ? ";
          PreparedStatement prepStmt =
                  con.prepareStatement(selectStatement);
          prepStmt.setString(1, primaryKey);

          ResultSet rs = prepStmt.executeQuery();
          boolean result = rs.next();
          prepStmt.close();
          releaseConnection();
          System.out.println("managerBean selectByPrimaryKey out");
          return result;
      }//selectByPrimaryKey

      private void loadManager() throws SQLException {

          System.out.println("managerBean loadmanager in");

          makeConnection();
          String selectStatement =
                  "select name, password " +
                  "from manager where managerID = ? ";
          PreparedStatement prepStmt =
                  con.prepareStatement(selectStatement);

          prepStmt.setString(1, managerID);

          ResultSet rs = prepStmt.executeQuery();

          if (rs.next())
          {
              name = rs.getString(1);
              password = rs.getString(2);
              prepStmt.close();
              releaseConnection();
          }
          else {
              prepStmt.close();
              releaseConnection();
              throw new NoSuchEntityException("loadmanager:Row for id " +
                  managerID + " not found in database.");
          }
          System.out.println("managerBean loadmanager out");
      }//loadmanager

      private void storeManager() throws SQLException {

          System.out.println("managerBean storemanager in");

          makeConnection();

          String updateStatement =
                  "update manager " +
                  "set name = ? , password = ? " +
                  "where managerID = ? ";
          PreparedStatement prepStmt =
                  con.prepareStatement(updateStatement);

          prepStmt.setString(1,name);
          prepStmt.setString(2, password);
          prepStmt.setString(3,managerID);

          int rowCount = prepStmt.executeUpdate();
          prepStmt.close();
          releaseConnection();

          if (rowCount == 0) {
              throw new EJBException("storemanager:Storing row for id " + managerID + " failed.");
          }
          System.out.println("managerBean storemanager out");
      }//storemanager

      private void deleteRow(String id) throws SQLException {

          System.out.println("managerBean deleteRow in");

          makeConnection();
          String deleteStatement =
                  "delete from manager where managerID = ? ";
          PreparedStatement prepStmt =
                  con.prepareStatement(deleteStatement);

          prepStmt.setString(1, id);
          prepStmt.executeUpdate();
          prepStmt.close();
          releaseConnection();
          System.out.println("managerBean deleteRow out");
      }////deleteRow

}