Java implements Zip compressed files and can download

1. Project requirements: After packaging multiple files, put them locally to provide download requirements.

2. Implementation ideas: use org.apache.tools.zip.ZipOutputStream.

3. Implementation code:

(1) Make a compressed tool class

package com.thinkgem.jeesite.modules.data.utils;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.zip.CRC32;
import java.util.zip.CheckedOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class ZipCompressor {
   static final int BUFFER = 8192;

   private File zipFile;

   public ZipCompressor(String pathName) {
       zipFile = new File(pathName);
   }
   public void compress(String... pathName) {
       ZipOutputStream out = null;
       try {
           FileOutputStream fileOutputStream = new FileOutputStream(zipFile);
           CheckedOutputStream cos = new CheckedOutputStream(fileOutputStream,
                   new CRC32());
           out = new ZipOutputStream(cos);
           String basedir = "";
           for (int i=0;i<pathName.length;i++){
               compress(new File(pathName[i]), out, basedir);
           }
           out.close();
       } catch (Exception e) {
           throw new RuntimeException(e);
       }
   }
   public void compress(String srcPathName) {
       File file = new File(srcPathName);
       if (!file.exists())
           throw new RuntimeException(srcPathName + "不存在！");
       try {
           FileOutputStream fileOutputStream = new FileOutputStream(zipFile);
           CheckedOutputStream cos = new CheckedOutputStream(fileOutputStream,
                   new CRC32());
           ZipOutputStream out = new ZipOutputStream(cos);
           String basedir = "";
           compress(file, out, basedir);
           out.close();
       } catch (Exception e) {
           throw new RuntimeException(e);
       }
   }

   private void compress(File file, ZipOutputStream out, String basedir) {
       /* Determine whether it is a directory or a file*/
       if (file.isDirectory()) {
           System.out.println("Compression:" + basedir + file.getName() );
           this.compressDirectory(file, out, basedir);
       } else {
           System.out.println("Compression: " + basedir + file.getName());
           this.compressFile(file, out, basedir);
       }
   }

   / ** Compress a directory*/
   private void compressDirectory(File dir, ZipOutputStream out, String basedir) {
       if (!dir.exists())
           return;

       File[] files = dir.listFiles();
       for (int i = 0; i < files.length; i++) {
           /* 递归 */
           compress(files[i], out, basedir + dir.getName() + "/");
       }
   }

   /** 压缩一个文件 */
   private void compressFile(File file, ZipOutputStream out, String basedir) {
       if (!file.exists()) {
           return;
       }
       try {
           BufferedInputStream bis = new BufferedInputStream(
                   new FileInputStream(file));
           ZipEntry entry = new ZipEntry(basedir + file.getName());
           out.putNextEntry(entry);
           int count;
           byte data[] = new byte[BUFFER];
           while ((count = bis.read(data, 0, BUFFER)) != -1) {
               out.write(data, 0, count);
           }
           bis.close();
       } catch (Exception e) {
           throw new RuntimeException(e);
       }
   }
public static void main(String[] args) {
       ZipCompressor zc = new ZipCompressor("E:/resource/resource.zip");
       zc.compress("E:/resource/js","E:/resource/css","E:/resource/images");
   }
}

(2) call the class

        //The path to store the Zip file
       String path = fileRoot + productService.getCode() + productService.getTypeCode() + ".zip";

       File file = new File(path);
       if(!file.exists()) {// Path to multiple files to be packed
           String[] str = (String[])strArray.toArray(new String[strArray.size()]);
           ZipCompressor zc = new ZipCompressor(path);
            zc.compress(str);
       }

(3) Provide a method for downloading

@RequestMapping(value = "downLoadZipFile")
    public void estampDown(HttpServletRequest request, HttpServletResponse response) {

        try {
           String code = request.getParameter("code");
           String typeCode = request.getParameter("typeCode");
           String fileRoot = Global.getConfig("fileRoot");
           String path = fileRoot + code + typeCode + ".zip";

           File file = new File(path); // 要下载的文件绝对路径
            InputStream ins;

            ins = new BufferedInputStream(new FileInputStream(file));

            byte[] buffer = new byte[ins.available()];
            ins.read(buffer);
            ins.close();

            response.reset();
            response.addHeader("Content-Disposition", "attachment;filename="+ new String(file.getName().getBytes()));
            response.addHeader("Content-Length", "" + file.length());
            OutputStream ous = new BufferedOutputStream(response.getOutputStream());
            response.setContentType("application/octet-stream");
            ous.write(buffer);
            ous.flush();
            ous.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

Links to related materials (thanks):

https://blog.csdn.net/xinqiku/article/details/79656829

http://blog.163.com/shanqing_shuixiu@yeah/blog/static/165319229201192444434865/

Java implements Zip compressed files and can download

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