package stocks;
import java.io.*;
import java.sql.*;
import javax.sql.*;
// Bean class for session bean "StockQuotes"
import javax.ejb.*;
import javax.naming.*;
import java.rmi.*;
public class StockQuotesBean implements javax.ejb.SessionBean {
//Instance member variables.
//
public String stock = null;
int nPurchased = 0;
float purchasePrice = 0.0F;
// Session context, can be used to obtain handles etc
//
javax.ejb.SessionContext ejbSessionContext = null;
//Getter/setter methods
//
public String getStock() throws java.rmi.RemoteException
{
return stock;
}
public void setStock( String stock ) throws java.rmi.RemoteException
{
this.stock = stock;
}
public float getPrice() throws java.rmi.RemoteException,
java.io.IOException, NamingException, SQLException
{
DataSource dataSource = (DataSource) (new InitialContext()).lookup( "java:comp/env/jdbc/stocksDataSource" );
Connection con = dataSource.getConnection();
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery( "SELECT MIN(StockPrice) FROM Stocks WHERE StockName='" + stock + "'" );
if ( ! rs.next()) {
stmt.close();
con.close();
throw new java.rmi.RemoteException( "Not found" );
}
float result = rs.getFloat(1);
stmt.close();
con.close();
if ( result == 0.0 )
throw new java.rmi.RemoteException( "Not found" );
return result;
}
public int getNumber() throws java.rmi.RemoteException, NamingException, SQLException
{
DataSource dataSource = (DataSource) (new InitialContext()).lookup( "java:comp/env/jdbc/stocksDataSource" );
Connection con = dataSource.getConnection();
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery( "SELECT NumberAvailable FROM Stocks WHERE StockName='" + stock + "' AND StockPrice=(SELECT MIN(StockPrice) FROM Stocks WHERE StockName='" + stock + "')" );
if ( ! rs.next()) {
stmt.close();
con.close();
return 0;
}
int result = rs.getInt(1);
stmt.close();
con.close();
return result;
}
public boolean buy( float maxPrice, int maxAmount ) throws java.rmi.RemoteException, NamingException, SQLException
{
// EJB Container takes care of the transaction handling.
DataSource dataSource = (DataSource) (new InitialContext()).lookup( "java:comp/env/jdbc/stocksDataSource" );
Connection con = dataSource.getConnection();
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery( "SELECT NumberAvailable,StockPrice FROM Stocks WHERE StockPrice < " + maxPrice + " AND StockName='" + stock + "' AND StockPrice=(SELECT MIN(StockPrice) FROM Stocks WHERE StockName='" + stock + "')" );
if ( ! rs.next()) {
stmt.close();
con.close();
return false;
}
int number = rs.getInt( 1 );
purchasePrice = rs.getFloat(2);
rs.close();
if ( number > maxAmount ) {
int newNumber = number - maxAmount;
stmt.executeUpdate( "UPDATE Stocks SET NumberAvailable=" + newNumber + " WHERE StockPrice=" + purchasePrice + " AND StockName='" + stock + "'" );
nPurchased = maxAmount;
} else {
stmt.executeUpdate( "DELETE FROM Stocks WHERE StockPrice=" + purchasePrice + " AND StockName='" + stock + "'" );
nPurchased = number;
}
stmt.close();
con.close();
return true;
}
public int getNumPurchased() throws java.rmi.RemoteException
{
return nPurchased;
}
public float getPurchasePrice() throws java.rmi.RemoteException
{
return purchasePrice;
}
// The default ejbCreate method.
//
public void ejbCreate(
String stock
)
throws javax.ejb.CreateException, java.rmi.RemoteException
{
this.stock = stock;
}
// TBD: If any other ejbCreate's are added manually to the home interface, define them.
//
// Other methods required in a session bean
//
public void setSessionContext( javax.ejb.SessionContext ejbSessionContext )
throws RemoteException
{
this.ejbSessionContext = ejbSessionContext;
}
public void unsetSessionContext()
throws RemoteException
{
this.ejbSessionContext = null;
}
public void ejbRemove()
throws java.rmi.RemoteException, javax.ejb.EJBException
{
// TBD: Do any processing here when instance is being removed
}
public void ejbActivate()
throws java.rmi.RemoteException
{
// TBD: Restore any saved resources
}
public void ejbPassivate()
throws java.rmi.RemoteException
{
// TBD: Save any resources here before bean is passivated
}
}