Note : In this tutorial i will use this library :-
- JSTL 1.1
The JSP File
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Download File As ZIP File</title>
</head>
<body>
<h1>Download File As ZIP File</h1>
${DownloadMessage}
<br/>
<form action="<c:url value="/downloadFileServletZip" />" method="post" >
Default Path is server to download is D:\JAVA\dist\Output\
<input type="submit" name="bDownload" value="Download Zip file"/>
</form>
</body>
</html>
The Servlet
import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class downloadFileServletZip extends HttpServlet {
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
String path = "D:\\JAVA\\dist\\Output\\";
File directory = new File(path);
String[] files = directory.list();
//check if directories have files
if (files != null && files.length > 0) {
//create zip stream
byte[] zip = zipFiles(directory, files);
// Sends the response back to the user / browser with zip content
ServletOutputStream sos = response.getOutputStream();
response.setContentType("application/zip");
response.setHeader("Content-Disposition", "attachment; filename=\"DATA.ZIP\"");
sos.write(zip);
sos.flush();
}
request.setAttribute("DownloadMessage", "Successfully");
request.getRequestDispatcher("DownloadZipFile.jsp").forward(request, response);
}
private byte[] zipFiles(File directory, String[] files) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ZipOutputStream zos = new ZipOutputStream(baos);
byte bytes[] = new byte[4096];
for (String fileName : files) {
try (FileInputStream fis = new FileInputStream(directory.getPath()
+ "/" + fileName);
BufferedInputStream bis = new BufferedInputStream(fis)) {
zos.putNextEntry(new ZipEntry(fileName));
int bytesRead;
while ((bytesRead = bis.read(bytes)) != -1) {
zos.write(bytes, 0, bytesRead);
}
zos.closeEntry();
}
}
zos.flush();
baos.flush();
zos.close();
baos.close();
return baos.toByteArray();
}
}
The Web.xml
<servlet-mapping> <servlet-name>downloadFileServletZip</servlet-name> <url-pattern>/downloadFileServletZip</url-pattern> </servlet-mapping> <servlet> <servlet-name>downloadFileServletZip</servlet-name> <servlet-class>sys.servlet.downloadFileServletZip</servlet-class> </servlet>
.bmp)
Note : This code will throw exception Access denied if the folder to create zip file contain subfolder.
By Mohd Zulkamal
NOTE : – If You have Found this post Helpful, I will appreciate if you can Share it on Facebook, Twitter and Other Social Media Sites. Thanks =)
0 comments:
Post a Comment