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1 package edu.rice.rubis.servlets;
2
3 import java.io.IOException  ;
4 import java.sql.Connection ;
5 import java.sql.PreparedStatement ;
6 import java.sql.ResultSet ;
7 import java.sql.SQLException ;
8
9 import javax.servlet.ServletException ;
10 import javax.servlet.http.HttpServletRequest ;
11 import javax.servlet.http.HttpServletResponse ;
12
13
15 public class BrowseCategories extends RubisHttpServlet
16 {
17
18
19
20 public int getPoolSize()
21 {
22 return Config.BrowseCategoriesPoolSize;
23 }
24
25
28 private void closeConnection(PreparedStatement stmt, Connection conn)
29 {
30 try
31 {
32 if (stmt != null)
33 stmt.close(); if (conn != null)
35 releaseConnection(conn);
36 }
37 catch (Exception ignore)
38 {
39 }
40 }
41
42
43 private boolean categoryList(int regionId, int userId, PreparedStatement stmt, Connection conn, ServletPrinter sp)
44 {
45 String categoryName;
46 int categoryId;
47 ResultSet rs = null;
48
49 try
51 {
52 stmt = conn.prepareStatement("SELECT name, id FROM categories");
53 rs = stmt.executeQuery();
54 }
55 catch (Exception e)
56 {
57 sp.printHTML("Failed to execute Query for categories list: " + e);
58 closeConnection(stmt, conn);
59 return false;
60 }
61 try
62 {
63 if (!rs.first())
64 {
65 sp.printHTML(
66 "<h2>Sorry, but there is no category available at this time. Database table is empty</h2><br>");
67 closeConnection(stmt, conn);
68 return false;
69 }
70 else
71 sp.printHTML("<h2>Currently available categories</h2><br>");
72
73 do
74 {
75 categoryName = rs.getString("name");
76 categoryId = rs.getInt("id");
77
78 if (regionId != -1)
79 {
80 sp.printCategoryByRegion(categoryName, categoryId, regionId);
81 }
82 else
83 {
84 if (userId != -1)
85 sp.printCategoryToSellItem(categoryName, categoryId, userId);
86 else
87 sp.printCategory(categoryName, categoryId);
88 }
89 }
90 while (rs.next());
91 }
92 catch (Exception e)
93 {
94 sp.printHTML("Exception getting categories list: " + e + "<br>");
95 closeConnection(stmt, conn);
96 return false;
97 }
98 return true;
99 }
100
101
102 public void doGet(HttpServletRequest request, HttpServletResponse response)
103 throws IOException , ServletException
104 {
105 ServletPrinter sp = null;
106 PreparedStatement stmt = null;
107 Connection conn = null;
108 int regionId = -1, userId = -1;
109 String username = null, password = null;
110
111 sp = new ServletPrinter(response, "BrowseCategories");
112 sp.printHTMLheader("RUBiS available categories");
113
114 username = request.getParameter("nickname");
115 password = request.getParameter("password");
116
117 conn = getConnection();
118
119 if ((username != null && username != "")
121 || (password != null && password != ""))
122 {
123 Auth auth = new Auth(conn, sp);
124 userId = auth.authenticate(username, password);
125 if (userId == -1)
126 {
127 sp.printHTML(
128 " You don't have an account on RUBiS!<br>You have to register first.<br>");
129 sp.printHTMLfooter();
130 closeConnection(stmt, conn);
131 return;
132 }
133 }
134
135 String value = request.getParameter("region");
136 if ((value != null) && (!value.equals("")))
137 {
138 try
140 {
141 stmt = conn.prepareStatement("SELECT id FROM regions WHERE name=?");
142 stmt.setString(1, value);
143 ResultSet rs = stmt.executeQuery();
144 if (!rs.first())
145 {
146 sp.printHTML(
147 " Region " + value + " does not exist in the database!<br>");
148 closeConnection(stmt, conn);
149 return;
150 }
151 regionId = rs.getInt("id");
152 stmt.close();
153 }
154 catch (SQLException e)
155 {
156 sp.printHTML("Failed to execute Query for region: " + e);
157 closeConnection(stmt, conn);
158 return;
159 }
160 }
161
162 boolean connAlive = categoryList(regionId, userId, stmt, conn, sp);
163 if (connAlive) {
164 closeConnection(stmt, conn);
165 }
166 sp.printHTMLfooter();
167
168 }
169
170 public void doPost(HttpServletRequest request, HttpServletResponse response)
171 throws IOException , ServletException
172 {
173 doGet(request, response);
174 }
175
176
179 public void destroy()
180 {
181 super.destroy();
182 }
183
184 }
185 |
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