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1 package edu.rice.rubis.beans;
2
3 import java.rmi.RemoteException  ;
4 import javax.ejb.SessionBean ;
5 import javax.ejb.SessionContext ;
6 import javax.ejb.FinderException ;
7 import javax.ejb.ObjectNotFoundException ;
8 import javax.ejb.CreateException ;
9 import javax.ejb.RemoveException ;
10 import javax.ejb.EJBException ;
11 import javax.naming.Context ;
12 import javax.naming.InitialContext ;
13 import javax.rmi.PortableRemoteObject ;
14 import javax.sql.DataSource ;
15 import java.sql.Connection ;
16 import java.sql.PreparedStatement ;
17 import java.sql.ResultSet ;
18 import java.sql.SQLException ;
19 import java.io.Serializable ;
20 import javax.transaction.UserTransaction ;
21
22
28
29 public class SB_StoreBidBean implements SessionBean
30 {
31 protected SessionContext sessionContext;
32 protected Context initialContext = null;
33 protected DataSource dataSource = null;
34 private UserTransaction utx = null;
35
36
46 public void createBid(int userId, int itemId, float bid, float maxBid, int qty) throws RemoteException
47 {
48 PreparedStatement stmt = null;
49 ResultSet rs = null;
50 Connection conn = null;
51
52 utx = sessionContext.getUserTransaction();
53 try
54 {
55 utx.begin();
56 try
57 {
58 conn = dataSource.getConnection();
60 String now = TimeManagement.currentDateToString();
61 stmt = conn.prepareStatement("INSERT INTO bids VALUES (NULL, \""+userId+
62 "\", \""+itemId+"\", \""+qty+"\", \""+
63 bid+"\", \""+maxBid+"\", \""+now+"\")");
64 stmt.executeUpdate();
65 stmt.close();
66 }
67 catch (SQLException e)
68 {
69 try { stmt.close(); } catch (Exception ignore) {}
70 try { conn.close(); } catch (Exception ignore) {}
71 throw new RemoteException ("Error while storing the bid (got exception: " +e+")<br>");
72 }
73 PreparedStatement update = null;
75 try
76 {
77 stmt = conn.prepareStatement("SELECT nb_of_bids, max_bid FROM items WHERE id=?");
78 stmt.setInt(1, itemId);
79 rs = stmt.executeQuery();
80
81 if (rs.first())
82 {
83 int nbOfBids = rs.getInt("nb_of_bids");
84 nbOfBids++;
85 float oldMaxBid = rs.getFloat("max_bid");
86 if (bid > oldMaxBid)
87 {
88 oldMaxBid = bid;
89 update = conn.prepareStatement("UPDATE items SET max_bid=?,nb_of_bids=? WHERE id=?");
90 update.setFloat(1, oldMaxBid);
91 update.setInt(2, nbOfBids);
92 update.setInt(3, itemId);
93 update.executeUpdate();
94 }
95 else
96 {
97 update = conn.prepareStatement("UPDATE items SET nb_of_bids=? WHERE id=?");
98 update.setInt(1, nbOfBids);
99 update.setInt(2, itemId);
100 update.executeUpdate();
101 }
102 stmt.close();
103 update.close();
104 }
105 }
106 catch (Exception ex)
107 {
108 try { update.close(); } catch (Exception ignore) {}
109 try { stmt.close(); } catch (Exception ignore) {}
110 try { conn.close(); } catch (Exception ignore) {}
111 throw new RemoteException ("Failed to update nb of bids and max bid: " + ex);
112 }
113 if (conn != null) conn.close();
114 utx.commit();
115 }
116 catch (Exception e)
117 {
118 try { conn.close(); } catch (Exception ignore) {}
119 try
120 {
121 utx.rollback();
122 throw new RemoteException ("Failed to create a new bid (got exception: " +e+")<br>");
123 }
124 catch (Exception se)
125 {
126 throw new RemoteException ("Transaction rollback failed: " + e +"<br>");
127 }
128 }
129 }
130
131
132
133
135
138 public void ejbCreate() throws CreateException , RemoteException
139 {
140 }
141
142
143 public void ejbActivate() throws RemoteException {}
144
145 public void ejbPassivate() throws RemoteException {}
146
147 public void ejbRemove() throws RemoteException {}
148
149
150
159 public void setSessionContext(SessionContext sessionContext) throws RemoteException
160 {
161 this.sessionContext = sessionContext;
162 if (dataSource == null)
163 {
164
166 try
167 {
168 initialContext = new InitialContext ();
169 dataSource = (DataSource )initialContext.lookup("java:comp/env/jdbc/rubis");
170 }
171 catch (Exception e)
172 {
173 throw new RemoteException ("Cannot get JNDI InitialContext");
174 }
175 }
176 }
177
178 }
179 |
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