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1
24
25 package edu.rice.rubbos.servlets;
26
27 import java.io.IOException  ;
28 import java.net.URLEncoder ;
29 import java.sql.Connection ;
30 import java.sql.PreparedStatement ;
31 import java.sql.ResultSet ;
32
33 import javax.servlet.ServletException ;
34 import javax.servlet.http.HttpServletRequest ;
35 import javax.servlet.http.HttpServletResponse ;
36
37 public class BrowseStoriesByCategory extends RubbosHttpServlet
38 {
39
40 public int getPoolSize()
41 {
42 return Config.BrowseCategoriesPoolSize;
43 }
44
45 private void closeConnection(PreparedStatement stmt, Connection conn)
46 {
47 try
48 {
49 if (stmt != null)
50 stmt.close(); }
52 catch (Exception ignore)
53 {
54 }
55
56 try
57 {
58 if (conn != null)
59 releaseConnection(conn);
60 }
61 catch (Exception ignore)
62 {
63 }
64
65 }
66
67
68 public void doGet(HttpServletRequest request, HttpServletResponse response)
69 throws IOException , ServletException
70 {
71
72 ServletPrinter sp = null;
73 PreparedStatement stmt = null;
74 Connection conn = null;
75
76 sp = new ServletPrinter(response, "BrowseStoriesByCategory");
77
78 String categoryName, username, categoryId, testpage, testnbOfStories;
79 int page = 0, nbOfStories = 0;
80 ResultSet rs = null;
81
82 testpage = request.getParameter("page");
83 testnbOfStories = request.getParameter("nbOfStories");
84
85 if (testpage != null)
86 {
87 page = (Integer.valueOf(request.getParameter("page"))).intValue();
88 }
89
90 if (testnbOfStories != null)
91 {
92 nbOfStories = (Integer.valueOf(request.getParameter("nbOfStories")))
93 .intValue();
94 }
95
96 categoryId = request.getParameter("category");
97 categoryName = request.getParameter("categoryName");
98
99 if (categoryName == null)
100 {
101 sp.printHTML("Browse Stories By Category"
102 + "You must provide a category name!<br>");
103 return;
104 }
105
106 if (categoryId == null)
107 {
108 sp.printHTML("Browse Stories By Category"
109 + "You must provide a category identifier!<br>");
110 return;
111 }
112
113 if (page == 0)
114 {
115 page = 0;
116 }
117
118 if (nbOfStories == 0)
119 {
120 nbOfStories = 25;
121
122 }
123 sp.printHTMLheader("RUBBoS Browse Stories By Category");
124 sp.printHTML("<br><h2>Stories in category " + categoryName + "</h2><br>");
125
126 conn = getConnection();
127
128 try
129 {
130 stmt = conn.prepareStatement("SELECT * FROM stories WHERE category= "
131 + categoryId + " ORDER BY date DESC LIMIT " + page * nbOfStories
132 + "," + nbOfStories);
133 rs = stmt.executeQuery();
134 }
135 catch (Exception e)
136 {
137 sp.printHTML("Failed to execute Query for BrowseStoriesByCategory: " + e);
138 closeConnection(stmt, conn);
139 return;
140 }
141 try
142 {
143 if (!rs.first())
144 {
145 if (page == 0)
146 {
147 sp
148 .printHTML("<h2>Sorry, but there is no story available in this category !</h2>");
149 }
150 else
151 {
152 sp
153 .printHTML("<h2>Sorry, but there are no more stories available at this time.</h2><br>\n");
154 sp
155 .printHTML("<p><CENTER>\n<a HREF=\"/rubbos/servlet/edu.rice.rubbos.servlets.BrowseStoriesByCategory?category="
156 + categoryId
157 + "&categoryName="
158 + URLEncoder.encode(categoryName)
159 + "&page="
160 + (page - 1)
161 + "&nbOfStories=nbOfStories\">Previous page</a>\n</CENTER>\n");
162 }
163 sp.printHTMLfooter();
164 closeConnection(stmt, conn);
165 return;
166 }
167
168 do
169 {
170 String title = rs.getString("title");
171 String date = rs.getString("date");
172 username = rs.getString("writer");
173 int id = rs.getInt("id");
174
175 sp
176 .printHTML("<a HREF=\"/rubbos/servlet/edu.rice.rubbos.servlets.ViewStory?storyId="
177 + id
178 + "\">"
179 + title
180 + "</a> by "
181 + username
182 + " on "
183 + date
184 + "<br>\n");
185 }
186 while (rs.next());
187 }
188 catch (Exception e)
189 {
190 sp.printHTML("Exception getting categories: " + e + "<br>");
191 }
192
193 closeConnection(stmt, conn);
194
195
196 if (page == 0)
197 sp
198 .printHTML("<p><CENTER>\n<a HREF=\"/rubbos/servlet/edu.rice.rubbos.servlets.BrowseStoriesByCategory?category="
199 + categoryId
200 + "&categoryName="
201 + URLEncoder.encode(categoryName)
202 + "&page="
203 + (page + 1)
204 + "&nbOfStories="+nbOfStories+"\">Next page</a>\n</CENTER>\n");
205 else
206 sp
207 .printHTML("<p><CENTER>\n<a HREF=\"/rubbos/servlet/edu.rice.rubbos.servlets.BrowseStoriesByCategory?category="
208 + categoryId
209 + "&categoryName="
210 + URLEncoder.encode(categoryName)
211 + "&page="
212 + (page - 1)
213 + "&nbOfStories="+nbOfStories+"\">Previous page</a>\n   "
214 + "<a HREF=\"/rubbos/servlet/edu.rice.rubbos.servlets.BrowseStoriesByCategory?category="
215 + categoryId
216 + "&categoryName="
217 + URLEncoder.encode(categoryName)
218 + "&page="
219 + (page + 1)
220 + "&nbOfStories="+nbOfStories+"\">Next page</a>\n\n</CENTER>\n");
221
222 sp.printHTMLfooter();
223
224 }
225
226 public void doPost(HttpServletRequest request, HttpServletResponse response)
227 throws IOException , ServletException
228 {
229 doGet(request, response);
230 }
231
232 }
233 |
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