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1   /*
2    * $Header: /cvsroot/jdbforms/dbforms/src/org/dbforms/servlets/CSVReportServlet.java,v 1.5 2005/11/30 20:31:18 hkollmann Exp $
3    * $Revision: 1.5 $
4    * $Date: 2005/11/30 20:31:18 $
5    *
6    * DbForms - a Rapid Application Development Framework
7    * Copyright (C) 2001 Joachim Peer <joepeer@excite.com>
8    *
9    * This library is free software; you can redistribute it and/or
10   * modify it under the terms of the GNU Lesser General Public
11   * License as published by the Free Software Foundation; either
12   * version 2.1 of the License, or (at your option) any later version.
13   *
14   * This library is distributed in the hope that it will be useful,
15   * but WITHOUT ANY WARRANTY; without even the implied warranty of
16   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17   * Lesser General Public License for more details.
18   *
19   * You should have received a copy of the GNU Lesser General Public
20   * License along with this library; if not, write to the Free Software
21   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
22   */
23  
24  package org.dbforms.servlets;
25  
26  import org.dbforms.servlets.reports.AbstractLineReportServlet;
27  
28  import java.io.OutputStream;
29  import java.io.OutputStreamWriter;
30  import java.io.PrintWriter;
31  
32  /***
33   * This servlet generates a comma separated values file (CSV). Data is read from
34   * the current dbForm, a Collection or a ResultSetVector The template file is in
35   * the reports directory with a .cr extension it consists of two lines of text,
36   * the first is a list of stirngs to use as header the second a list of comma
37   * separated field names. both lines must have the same number of elements.
38   * Normally the output file will use the first row as the headers. But if no
39   * header line is provided, then no headers are output and every row is data.
40   * usage: with a simple goto button: &lt;db:gotoButton destTable="web_parts"
41   * destination=" /reports/Artikel"/&gt; or for one record: &lt;db:gotoButton
42   * destTable="web_parts" keyToDestPos="currentRow"
43   * destination="/reports/Artikel" /&gt; Servlet mapping must be set to handle
44   * all /reports by this servlet!!! &lt;servlet/&gt;
45   * &lt;servlet-name/&gt;startreport&lt;/servlet-name/&gt;
46   * &lt;display-name/&gt;startreport&lt;/display-name/&gt;
47   * &lt;servlet-class/&gt;org.dbforms.StartReportServlet&lt;/servlet-class/&gt;
48   * &lt;/servlet&gt; &lt;servlet-mapping/&gt;
49   * &lt;servlet-name/&gt;startreport&lt;/servlet-name/&gt;
50   * &lt;url-pattern/&gt;/reports/&lt;/url-pattern/&gt; &lt;/servlet-mapping&gt;
51   * web.xml optional parameters reportdirs list of directories to search for
52   * report file reportMimeType mime type to send to browser Parameters
53   * filename=xyz.csv name the output file Support for grabbing data from a
54   * Collection or an existing ResultSetVector set session variable "jasper.input"
55   * to use a Collection object set session variable "jasper.rsv" to use a
56   * ResultSetVector object ex &ltc:set var="jasper.rsv" value="${rsv_xxxxx}"
57   * scope="session" /&gt
58   * 
59   * @author Neal Katz
60   */
61  public class CSVReportServlet extends AbstractLineReportServlet {
62  
63  	private static final char Q = '\"';
64  
65  	private static final String DEFAULTMIMETYPE = "text/comma-separated-values;charset=ASCII";
66  
67  	private String clean(String s) {
68  		s = s.replaceAll("\"", "//\"");
69  		return s;
70  	}
71  
72  	protected String getMimeType() {
73  		return DEFAULTMIMETYPE;
74  	}
75  
76  	protected String getFileExtension() {
77  		return ".csv";
78  	}
79  
80  	private PrintWriter pw;
81  
82  	protected void openStream(OutputStream out)  throws Exception {
83  		OutputStreamWriter osw;
84  		try {
85  			osw = new OutputStreamWriter(out, "UTF8");
86  		} catch (Exception e) {
87  			osw = new OutputStreamWriter(out);
88  		}
89  		pw = new PrintWriter(osw);
90  	}
91  
92  	protected void closeStream(OutputStream out)  throws Exception {
93  		pw.flush();
94  		pw.close();
95  	}
96  
97  	protected void writeData(Object[] data) throws Exception {
98  		for (int i = 0; i < data.length; i++) {
99  			if (i > 0) {
100 				pw.print(',');
101 			}
102 			if (data[i] != null) {
103 				pw.print(Q + clean(data[i].toString()) + Q);
104 			} else {
105 				pw.print(Q + "" + Q);
106 			}
107 		}
108 		pw.println();
109 	}
110 
111 }