com.mockrunner.example.ejb.PaySessionBean Maven / Gradle / Ivy
package com.mockrunner.example.ejb;
import java.rmi.RemoteException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import javax.ejb.CreateException;
import javax.ejb.EJBException;
import javax.ejb.SessionBean;
import javax.ejb.SessionContext;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;
/*
* @ejb:bean name="PaySession"
* display-name="PaySessionBean"
* type="Stateless"
* transaction-type="Container"
* jndi-name="com/mockrunner/example/PaySession"
*
* @ejb:resource-ref res-ref-name="jdbc/MySQLDB"
* res-type="javax.sql.DataSource"
* res-auth="Container"
* res-sharing-scope="Shareable"
*
* @jboss:resource-manager res-man-name="jdbc/MySQLDB"
* res-man-jndi-name="java:/MySQLDB"
*/
/**
* This is the EJB-version of
* com.mockrunner.example.jdbc.PayAction.
* It throws a PaySessionException in case of error.
*/
public class PaySessionBean implements SessionBean
{
private SessionContext sessionContext;
/*
* @ejb:interface-method
* @ejb:transaction type="Required"
*/
public void payBill(String customerId, String billId, double amount) throws PaySessionException
{
Connection connection = null;
try
{
InitialContext context = new InitialContext();
DataSource dataSource = (DataSource)context.lookup("java:comp/env/jdbc/MySQLDB");
connection = dataSource.getConnection();
String name = getName(connection, customerId);
if(null == name)
{
sessionContext.setRollbackOnly();
throw new PaySessionException(PaySessionException.UNKNOWN_CUSTOMER);
}
checkBillIntegrity(connection, customerId, billId, amount);
markBillAsPaid(connection, customerId, billId, amount);
System.out.println(amount + " paid from customer " + name);
}
catch(NamingException exc)
{
sessionContext.setRollbackOnly();
throw new EJBException("JNDI error " + exc.getMessage());
}
catch(SQLException exc)
{
sessionContext.setRollbackOnly();
throw new EJBException("Database error " + exc.getMessage());
}
finally
{
try
{
if(null != connection) connection.close();
}
catch(SQLException ignored)
{
}
}
}
private String getName(Connection connection, String customerId) throws SQLException
{
Statement statement = connection.createStatement();
ResultSet result = statement.executeQuery("select name from customers where id='" + customerId + "'");
String name = null;
if(result.next())
{
name = result.getString("name");
}
result.close();
statement.close();
return name;
}
private void checkBillIntegrity(Connection connection, String customerId, String billId, double amount) throws SQLException, PaySessionException
{
Statement statement = connection.createStatement();
ResultSet result = statement.executeQuery("select * from openbills where id='" + billId + "'");
try
{
if(false == result.next())
{
sessionContext.setRollbackOnly();
throw new PaySessionException(PaySessionException.UNKNOWN_BILL);
}
if(!result.getString("customerid").equals(customerId))
{
sessionContext.setRollbackOnly();
throw new PaySessionException(PaySessionException.WRONG_BILL_FOR_CUSTOMER);
}
if(result.getDouble("amount") != amount)
{
sessionContext.setRollbackOnly();
throw new PaySessionException(PaySessionException.WRONG_AMOUNT_FOR_BILL);
}
}
finally
{
result.close();
statement.close();
}
}
private void markBillAsPaid(Connection connection, String customerId, String billId, double amount) throws SQLException
{
Statement statement = connection.createStatement();
statement.executeUpdate("delete from openbills where id='" + billId + "'");
statement.executeUpdate("insert into paidbills values('" + billId + "','" + customerId + "'," + amount + ")");
statement.close();
}
/*
* @ejb:create-method
*/
public void ejbCreate() throws CreateException
{
}
public void ejbActivate() throws EJBException, RemoteException
{
}
public void ejbPassivate() throws EJBException, RemoteException
{
}
public void ejbRemove() throws EJBException, RemoteException
{
}
public void setSessionContext(SessionContext sessionContext) throws EJBException, RemoteException
{
this.sessionContext = sessionContext;
}
}