package com.servlet;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.URLEncoder;
import java.util.Iterator;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.RequestContext;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.commons.fileupload.servlet.ServletRequestContext;
import org.apache.commons.io.FileUtils;

import com.constant.FileUploadConstant;
import com.constant.LogoEnum;
import com.google.zxing.common.StringUtils;
import com.util.QRCodeUtil;
import com.util.UniqueUtil;

public class QRDownloadServlet extends HttpServlet{
	
	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		// TODO Auto-generated method stub
		super.doPost(req, resp);
	}
	
	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
		// TODO Auto-generated method stub

		String qrName = req.getParameter("qrName");
		String qrPath = req.getServletContext().getRealPath(FileUploadConstant.QR_PATH)+File.separator+qrName;
		File file = new File(qrPath);
		if(file.exists()){
			 String filename = URLEncoder.encode(file.getName(), "utf-8");
			 resp.reset();
			 resp.addHeader("Content-Disposition", "attachment; filename=\"" + filename + "\"");
	         int fileLength = (int) file.length();
	         resp.setContentLength(fileLength);
	         /*如果文件长度大于0*/
	         if (fileLength != 0) {
	        	 	/*创建输入流*/
	                InputStream inStream = new FileInputStream(file);
	                byte[] buf = new byte[4096];
	                /*创建输出流*/
	                ServletOutputStream servletOS = resp.getOutputStream();
	                int readLength;
	                while (((readLength = inStream.read(buf)) != -1)) {
	                    servletOS.write(buf, 0, readLength);
	                }
	                inStream.close();
	                servletOS.flush();
	                servletOS.close();
	            }
		}
		
	}

}