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1
32
33 package com.knowgate.http;
34
35 import java.io.InputStream  ;
36 import java.io.IOException ;
37 import java.io.FileNotFoundException ;
38 import javax.servlet.*;
39 import javax.servlet.http.*;
40
41 import java.lang.System ;
42 import java.util.StringTokenizer ;
43 import java.util.Properties ;
44
45 import java.sql.DriverManager ;
46 import java.sql.SQLException ;
47 import java.sql.Connection ;
48 import java.sql.PreparedStatement ;
49 import java.sql.ResultSet ;
50
51 import com.knowgate.debug.DebugFile;
52 import com.knowgate.misc.Environment;
53
54
59
60 public class HttpBLOBServlet extends HttpServlet {
61
62
64 private boolean isVoid(String sParam) {
65 if (null==sParam)
66 return true;
67 else
68 return (sParam.length()==0);
69 }
70
71
82
83 public void init() throws ServletException {
84 ServletConfig config = getServletConfig();
85
86 jdbcDriverClassName = config.getInitParameter("jdbcDriverClassName");
87 jdbcURL = config.getInitParameter("jdbcURL");
88 dbUserName = config.getInitParameter("dbUserName");
89 dbUserPassword = config.getInitParameter("dbUserPassword");
90
91 if (isVoid(jdbcDriverClassName) || isVoid(jdbcURL) || isVoid(dbUserName) || isVoid(dbUserPassword)) {
92 Properties env = Environment.getProfile("hipergate");
93
94 if (isVoid(jdbcDriverClassName))
95 jdbcDriverClassName = env.getProperty("driver");
96
97 if (isVoid(jdbcURL))
98 jdbcURL = env.getProperty("dburl");
99
100 if (isVoid(dbUserName))
101 dbUserName = env.getProperty("dbuser");
102
103 if (isVoid(dbUserPassword))
104 dbUserPassword = env.getProperty("dbpassword");
105 }
106
107 if (jdbcDriverClassName == null || jdbcURL == null) {
108 throw new UnavailableException("Init params missing");
109 }
110 }
112
114
123 public void doGet(HttpServletRequest request, HttpServletResponse response)
124 throws IOException , FileNotFoundException , ServletException
125 {
126 boolean bFound;
127 String sSQL;
128 Class oDriver;
129 Connection oConn = null;
130 PreparedStatement oStmt;
131 ResultSet oRSet;
132 InputStream oBlob = null;
133 int iOffset;
134 int iReaded;
135 int iPar;
136 StringTokenizer oStrTok;
137
138 if (DebugFile.trace) {
139 DebugFile.writeln("Begin HttpBLOBServlet().doGet");
140 DebugFile.incIdent();
141 }
142
143 try {
144 oDriver = Class.forName(jdbcDriverClassName);
145 }
146 catch (ClassNotFoundException ignore) {
147 oDriver = null;
148 if (DebugFile.trace) DebugFile.writeln("Class.forName(" + jdbcDriverClassName + ") : " + ignore.getMessage());
149 response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, "Database driver not found");
150 }
151
152 if (null==oDriver) return;
153
154 ServletOutputStream oOut = response.getOutputStream();
155
156 byte oBuffer[] = new byte[4004];
157
158 try {
159 if (DebugFile.trace) DebugFile.writeln("DriverManager.getConnection(" + jdbcURL + ",...)");
160
161 oConn = DriverManager.getConnection(jdbcURL,dbUserName,dbUserPassword);
162
163 if (DebugFile.trace) DebugFile.writeln("pk_field = " + (request.getParameter("pk_field")!=null ? request.getParameter("pk_field") : "null"));
164
165 oStrTok = new StringTokenizer (request.getParameter("pk_field"), ",");
166
167 sSQL = "";
168 while (oStrTok.hasMoreTokens()) {
169 sSQL += (sSQL.length()==0 ? " WHERE " : " AND ");
170 sSQL += oStrTok.nextToken() + "=?";
171 } sSQL = "SELECT " + request.getParameter("nm_field") + "," + request.getParameter("bin_field") + " FROM " + request.getParameter("nm_table") + sSQL;
173
174 if (DebugFile.trace) DebugFile.writeln("Connection.prepareStatement(" + sSQL + ")");
175
176 oStmt = oConn.prepareStatement (sSQL);
177
178 iPar = 0;
179 oStrTok = new StringTokenizer (request.getParameter("pk_value"), ",");
180 while (oStrTok.hasMoreTokens()) {
181 oStmt.setString(++iPar, oStrTok.nextToken());
182 }
183
184 if (DebugFile.trace) DebugFile.writeln("PreparedStatement.executeQuery()");
185
186 oRSet = oStmt.executeQuery();
187 bFound = oRSet.next();
188
189 String sFileName = null;
190
191 if (bFound) {
192
193 sFileName = oRSet.getString(1);
194
195 if (DebugFile.trace) {
196 DebugFile.writeln("response.setContentType(\"application/octet-stream\")");
197 DebugFile.writeln("response.setHeader(\"Content-Disposition\", \"inline; filename=\"" + sFileName + "\"");
198 }
199
200 response.setContentType("application/octet-stream");
202 response.setHeader("Content-Disposition", "inline; filename=\"" + sFileName + "\"");
203
204 if (DebugFile.trace)
205 DebugFile.writeln("ResultSet.getBinaryStream(2)");
206
207 oBlob = oRSet.getBinaryStream(2);
208 iOffset = 0;
209 do {
210 iReaded = oBlob.read(oBuffer, 0, 4000);
211 if (iReaded>0)
212 oOut.write(oBuffer, 0, iReaded);
213 iOffset += iReaded;
214 } while (4000==iReaded);
215
216 if (DebugFile.trace)
217 DebugFile.writeln("response.getOutputStream().flush()");
218
219 oOut.flush();
220 oBlob.close();
221 oBlob = null;
222 }
224 oRSet.close();
225
226 if (!bFound) {
227 if (DebugFile.trace) DebugFile.writeln("FileNotFoundException: Cannot find requested document");
228
229 response.sendError(HttpServletResponse.SC_NOT_FOUND, "Cannot find requested document");
230 }
231
232 oConn.close();
233 oConn = null;
234 }
235 catch (SQLException e) {
236 bFound = false;
237 if (oBlob!=null) oBlob.close();
238
239 if (DebugFile.trace) DebugFile.writeln("SQLException: " + e.getMessage());
240
241 response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR, e.getMessage());
242 }
243 try { if(null!=oConn) if(!oConn.isClosed()) oConn.close(); } catch (SQLException e) { }
244
245 if (DebugFile.trace) {
246 DebugFile.decIdent();
247 DebugFile.writeln("End HttpBLOBServlet().doGet()");
248 }
249 }
251
254 private String jdbcDriverClassName;
255 private String jdbcURL;
256 private String dbUserName;
257 private String dbUserPassword;
258 } |
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