package com;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.URLEncoder;
import java.util.Date;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.sun.xml.internal.messaging.saaj.packaging.mime.internet.MimeUtility;
/**
* File download class. In order to prevent the client browser directly open the target file (such as installed MS Office The suite Windows In the IE The browser will probably be right there IE Open whatever you want to download in your browser doc or xls File), in the response header to add the mandatory download MIME Type.
*/
public class DownloadFile extends HttpServlet {
private static final Log log = LogFactory.getLog(DownloadFile.class);
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException {
long timeStart = 0;
if(log.isDebugEnabled()){
timeStart=System.currentTimeMillis();
}
response.setContentType("application/x-download charset=UTF-8");
java.io.FileInputStream fis = null;
String filepath = request.getRealPath("");
javax.servlet.ServletOutputStream sos = null;
// System.out.println("DownloadFile filename:" + filename);
try {
if(request.getParameter("filename")==null
||request.getParameter("showName")==null){
return;
}
String filename = request.getParameter("filename");
String showName = request.getParameter("showName");
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
java.io.File file = new java.io.File(filepath + filename);
if (!file.exists()) {
log.error(file.getAbsolutePath() + " File does not exist !");
return;
}
// Read file stream
fis = new java.io.FileInputStream(file);
// Set the filename to save for download
sos = response.getOutputStream();
showName += filename.substring(filename.lastIndexOf("."));
String contentDisposition = "", browser = getBrowser(request);
if ("IE".equals(browser)) {
contentDisposition = "attachment; filename=" + URLEncoder.encode(showName, "UTF-8").replace("+", "%20");
} else if ("CH".equals(browser)) {
contentDisposition = "attachment; filename=" + MimeUtility.encodeText(showName, "UTF8", "B");
} else if ("SF".equals(browser)) {
contentDisposition = "attachment; filename=" + new String(showName.getBytes("UTF-8"), "ISO8859-1");
} else {
contentDisposition = "attachment; filename*=UTF-8''" + URLEncoder.encode(showName, "UTF-8").replace("+", "%20");
}
response.setHeader("Content-Disposition", contentDisposition);
int byteCount = 0;
if (fis != null) {
byte[] buff = new byte[1024];
int bytesRead;
while(-1 != (bytesRead = fis.read(buff, 0, buff.length))) {
sos.write(buff, 0, bytesRead);
sos.flush();
byteCount += bytesRead;
}
}
sos.flush();
if(log.isDebugEnabled()){
log.debug(" File download completed, file size: "+ byteCount +" , total time :"+ (new Date().getTime() - timeStart) +" Milliseconds. ");
}
} catch(IOException ioe) {
ioe.printStackTrace();
} finally {
try {
if(fis!=null){
fis.close();
}
} catch (IOException e) {
} finally {
try {
if(sos!=null){
sos.close();
}
} catch (IOException e) {
}
}
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">");
out.println("<html>");
out.println(" <head>");
out.println(" <title> File download </title>");
out.println(" <meta http-equiv=\"Content-Type\" content=\"text/html; charset=UTF-8\" />");
out.println(" </head>");
out.println(" <body>");
out.print(" This is ");
out.print(this.getClass().getName());
out.println(", using the POST method");
out.println(" </body>");
out.println("</html>");
out.flush();
out.close();
}
private String getBrowser(HttpServletRequest request) {
String userAgent = request.getHeader("USER-AGENT").toLowerCase();
if (userAgent != null) {
if (userAgent.indexOf("msie") >= 0) {
return "IE";
} else if (userAgent.indexOf("mozilla") >= 0) {
return "FF";
} else if (userAgent.indexOf("applewebkit") >= 0) {
return "CH";
} else if (userAgent.indexOf("safari") >= 0) {
return "SF";
} else if (userAgent.indexOf("opera") >= 0) {
return "OP";
}
}
return null;
}
}