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1
23
24 package org.dbforms.servlets;
25
26 import org.apache.commons.logging.Log;
27 import org.apache.commons.logging.LogFactory;
28
29 import org.dbforms.config.DbFormsConfig;
30 import org.dbforms.config.DbFormsConfigRegistry;
31 import org.dbforms.config.Field;
32 import org.dbforms.config.FieldTypes;
33 import org.dbforms.config.Table;
34
35 import org.dbforms.util.SqlUtil;
36 import org.dbforms.util.StringUtil;
37 import org.dbforms.util.Util;
38 import org.dbforms.util.FileHolder;
39
40 import java.io.IOException  ;
41 import java.io.InputStream ;
42
43 import java.sql.Connection ;
44 import java.sql.PreparedStatement ;
45 import java.sql.ResultSet ;
46 import java.sql.SQLException ;
47
48 import javax.servlet.ServletException ;
49 import javax.servlet.ServletOutputStream ;
50 import javax.servlet.http.HttpServlet ;
51 import javax.servlet.http.HttpServletRequest ;
52 import javax.servlet.http.HttpServletResponse ;
53
54
59 public class FileServlet extends HttpServlet {
60 private static Log logCat = LogFactory.getLog(FileServlet.class.getName());
62
63
76 public void doGet(HttpServletRequest request, HttpServletResponse response)
77 throws ServletException , IOException {
78
79 DbFormsConfig config = null;
83 try {
84 config = DbFormsConfigRegistry.instance().lookup();
85 } catch (Exception e) {
86 logCat.error(e);
87 throw new ServletException (e);
88 }
89
90 try {
91 String tf = request.getParameter("tf");
92 String keyValuesStr = request.getParameter("keyval");
93 if (!Util.isNull(keyValuesStr) && !("null".equals(keyValuesStr))) {
94
95 int tableId = Integer.parseInt(StringUtil.getEmbeddedString(tf,
96 0, '_'));
97 Table table = config.getTable(tableId);
98 int fieldId = Integer.parseInt(StringUtil.getEmbeddedString(tf,
99 1, '_'));
100 Field field = table.getField(fieldId);
101
102 StringBuffer queryBuf = new StringBuffer ();
103 String dbConnectionName = request.getParameter("invname_"
104 + tableId);
105 Connection con = config.getConnection(dbConnectionName);
106
107 String nameField = request.getParameter("nf");
109
110 InputStream is = null;
111 String fileName = null;
112
113 queryBuf.append("SELECT ");
114 queryBuf.append(field.getName());
115
116 if (nameField != null) {
117 queryBuf.append(", ");
118 queryBuf.append(nameField);
119 }
120
121 queryBuf.append(" FROM ");
122 queryBuf.append(table.getName());
123 queryBuf.append(" WHERE ");
124 queryBuf.append(table.getWhereClauseForKeyFields());
125
126 logCat.info("::doGet - query is [" + queryBuf + "]");
129
130 PreparedStatement ps = con
131 .prepareStatement(queryBuf.toString());
132 table.populateWhereClauseWithKeyFields(keyValuesStr, ps, 1);
133
134 ResultSet rs = ps.executeQuery();
135
136 if (rs.next()) {
137 if (field.getType() == FieldTypes.DISKBLOB) {
139 fileName = rs.getString(1);
140 is = SqlUtil.readDiskBlob(fileName, field
141 .getDirectory(), request
142 .getParameter("defaultValue"));
143 }
144 else if (field.getType() == FieldTypes.BLOB) {
146 if (nameField != null) {
148 fileName = rs.getString(2);
149 is = SqlUtil.readDbFieldBlob(rs);
150 } else {
151 FileHolder fh = SqlUtil.readFileHolderBlob(rs);
152 is = fh.getInputStreamFromBuffer();
153 fileName = fh.getFileName();
154 }
155 }
156 } else {
157 logCat.info("::doGet - we have got no result using query "
158 + queryBuf);
159 }
160
161 if (is != null) {
162 writeToClient(request, response, fileName, is);
163 }
164
165 SqlUtil.closeConnection(con);
166 }
167 } catch (SQLException sqle) {
168 logCat.error("::doGet - SQL exception", sqle);
169 }
170 }
171
172
185 public void doPost(HttpServletRequest request, HttpServletResponse response)
186 throws ServletException , IOException {
187 doGet(request, response);
188 }
189
190
205 private void writeToClient(HttpServletRequest request,
206 HttpServletResponse response, String fileName, InputStream is)
207 throws IOException {
208 String contentType = request.getSession().getServletContext()
209 .getMimeType(fileName);
210 logCat.info("::writeToClient- writing to client:" + fileName + " ct="
211 + contentType);
212
213 if (!Util.isNull(contentType)) {
214 response.setContentType(contentType);
215 }
216
217 response.setHeader("Cache-control", "private");
219 response.setHeader("Content-Disposition", "attachment; fileName=\""
221 + fileName + "\"");
222
223 ServletOutputStream out = response.getOutputStream();
224 byte[] b = new byte[1024];
225 int read;
226
227 while ((read = is.read(b)) != -1)
228 out.write(b, 0, read);
229
230 out.close();
231 }
232 }
233 |
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