java批量下载文件

通过打包的方式 批量下载文件

package com.szfa.cplib.exhh5server.controller;

import com.szfa.cplib.exhh5server.utils.httputils.OssUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

/**
 * @aouhor YangHuiLiang
 * @create 2020/5/11
 */
@RestController
@RequestMapping("test")
public class Test {
    @Autowired
    OssUtils ossUtils;

    @RequestMapping("test1")
    public HttpServletResponse test(HttpServletResponse response){
        return downLoadFiles(response);
    }

    //文件打包下载
    public HttpServletResponse downLoadFiles(HttpServletResponse response){
        try {
            //这个集合就是你想要打包的所有文件，这里假设已经准备好了所要打包的文件
            File f1 = new File("D:\\file\\1.png");
            File f2 = new File("D:\\file\\2.jpg");
            File f3 = new File("D:\\file\\3.jpg");
            List files = new ArrayList<>();
            files.add(f1);
            files.add(f2);
            files.add(f3);

            //创建一个临时压缩文件，我们会把文件流全部注入到这个文件中 这里的文件你可以自定义是.rar还是.zip*/
            File file = new File("d:/test.rar");
            if (!file.exists()) {
                file.createNewFile();
            }
            response.reset();

            //创建文件输出流
            FileOutputStream fous = new FileOutputStream(file);

            //打包的方法我们会用到ZipOutputStream这样一个输出流,所以这里我们把输出流转换一下
            ZipOutputStream zipOut = new ZipOutputStream(fous);

            //这个方法接收的就是一个所要打包文件的集合，还有一个ZipOutputStream
            zipFile(files, zipOut);

            zipOut.close();
            fous.close();
            return downloadZip(file, response);
        } catch (Exception e) {
            e.printStackTrace();
        }

        return response;
    }

    /**
     * 把接收的全部文件打成压缩包   
     */
    public void zipFile(List files, ZipOutputStream outputStream) {
        int size = files.size();
        for (int i = 0; i < size; i++) {
            File file = (File) files.get(i);
            zipFile(file, outputStream);
        }
    }

    public static HttpServletResponse downloadZip(File file, HttpServletResponse response) {
        try {
            // 以流的形式下载文件。
            InputStream fis = new BufferedInputStream(new FileInputStream(file.getPath()));
            byte[] buffer = new byte[fis.available()];
            fis.read(buffer);
            fis.close();

            // 清空response
            response.reset();

            OutputStream toClient = new BufferedOutputStream(response.getOutputStream());
            response.setContentType("application/octet-stream");
            response.setHeader("Content-Disposition", "attachment;filename=" + file.getName());
            toClient.write(buffer);
            toClient.flush();
            toClient.close();
        } catch (IOException ex) {
            ex.printStackTrace();
        } finally {
            try {
                File f = new File(file.getPath());
                f.delete();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return response;
    }


    /**
    * 根据输入的文件与输出流对文件进行打包   
     */
    public void zipFile(File inputFile,ZipOutputStream outputStream) {
        try {
            if (inputFile.exists()) {
                //如果是目录的话这里是不采取操作的，至于目录的打包正在研究中*/
                if (inputFile.isFile()) {
                    FileInputStream IN = new FileInputStream(inputFile);
                    BufferedInputStream bins = new BufferedInputStream(IN, 512);
                    ZipEntry entry = new ZipEntry(inputFile.getName());
                    outputStream.putNextEntry(entry);
                    // 向压缩文件中输出数据  
                    int nNumber;
                    byte[] buffer = new byte[512];
                    while ((nNumber = bins.read(buffer)) != -1) {
                        outputStream.write(buffer, 0, nNumber);
                    }
                    // 关闭创建的流对象  
                    bins.close();
                    IN.close();
                } else {
                    try {
                        File[] files = inputFile.listFiles();
                        for (int i = 0; i < files.length; i++) {
                            zipFile(files[i], outputStream);
                        }
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}