一个用servlet实现导出csv文件的实例

作者：李书鹏 tukeyli@sohu.com

关键字: Java Servlet CSV

本文实现了一个基于servlet技术的简单的csv文件导出的程序实例。

代码如下，其中setCsvData函数的作用是设置导出的数据，并将结果保存于Vector中，实际应用时可以任意扩展该函数：

package common;

import java.io.IOException;

import java.io.PrintWriter;

import java.util.Vector;

import javax.servlet.ServletException;

import javax.servlet.http.*;

public class Go2Csv extends HttpServlet

{

public Vector vecCsvData;

private String FileName;

public void doGet(HttpServletRequest request, HttpServletResponse response)

//throws ServletException, IOException

{

FileName = "Untitled.csv"; //default file name

vecCsvData = new Vector();

//sets the data to be exported

setCsvData(request);

//Exporting vector to csv file

String strOut = "";

for (int i = 0; i < vecCsvData.size(); i++)

{

String[] strLine = (String[])vecCsvData.elementAt(i);

int col_num = strLine.length;

for (int j = 0; j < col_num; j++)

{

strOut += strLine[j];

if (j < col_num - 1)

{

strOut += ",";

}

}

strOut += "/n";

}

//***** Output strOut to Response ******

response.reset(); // Reset the response

response.setContentType("application/octet-stream;charset=GB2312"); // the encoding of this example is GB2312

response.setHeader("Content-Disposition","attachment; filename=/"" + FileName + "/"");

PrintWriter out;

try

{

out = response.getWriter();

out.write(strOut);

}

catch (IOException e)

{

e.printStackTrace();

}

//***************************************

}

public void doPost(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException

{

doGet(request, response);

}

/**

* Sets the data to be exported

* @param request

*/

public void setCsvData(HttpServletRequest request)

{

//Writing vector

for (int i = 0; i < 5; i++)

{

String[] strLine = new String[10];

for (int j = 0; j < 10; j++)

{

strLine[j] = Integer.toString(i) + "-" + Integer.toString(j);

}

vecCsvData.addElement(strLine);

}

}

/**

* Sets the file name to be exported

* @param filename

*/

public void setFileName(String filename)

{

FileName = filename;

}

}

调用方法：
http://hostname:port/ApplicationName/servlet/common.Go2Csv
导出文件Untitled.csv内容如下：

0-0,0-1,0-2,0-3,0-4,0-5,0-6,0-7,0-8,0-9

1-0,1-1,1-2,1-3,1-4,1-5,1-6,1-7,1-8,1-9

2-0,2-1,2-2,2-3,2-4,2-5,2-6,2-7,2-8,2-9

3-0,3-1,3-2,3-3,3-4,3-5,3-6,3-7,3-8,3-9

4-0,4-1,4-2,4-3,4-4,4-5,4-6,4-7,4-8,4-9