Java实现zip压缩多个文件下载
为了更好的演示,首先创建一个文件实体FileBean,包含了文件路径和文件名称:
package com.javaweb.entity; import java.io.Serializable; /** * 文件实体类*/ public class FileBean implements Serializable{ private static final long serialVersionUID = -5452801884470115159L; private Integer fileId;//主键 private String filePath;//文件保存路径 private String fileName;//文件保存名称 public FileBean(){ } //Setters and Getters ... }
接下来,在控制层的方法里(示例为Spring MVC),进行读入多个文件List<FileBean>,压缩成myfile.zip输出到浏览器的客户端:
/** * 打包压缩下载文件 */ @RequestMapping(value = "/downLoadZipFile") public void downLoadZipFile(HttpServletResponse response) throws IOException{ String zipName = "myfile.zip";
List<FileBean> fileList = fileService.getFileList();//查询数据库中记录 response.setContentType("APPLICATION/OCTET-STREAM"); response.setHeader("Content-Disposition","attachment; filename="+zipName); ZipOutputStream out = new ZipOutputStream(response.getOutputStream()); try { for(Iterator<FileBean> it = fileList.iterator();it.hasNext();){ FileBean file = it.next(); ZipUtils.doCompress(file.getFilePath()+file.getFileName(), out); response.flushBuffer(); }
out.closeEntry();
} catch (Exception e) { e.printStackTrace(); }finally{ out.close(); } }
最后,附上ZipUtils压缩文件的工具类,这样便实现了多文件的压缩下载功能:
import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.util.zip.ZipEntry; import java.util.zip.ZipOutputStream; public class ZipUtils { private ZipUtils(){ } public static void doCompress(String srcFile, String zipFile) throws IOException { doCompress(new File(srcFile), new File(zipFile)); } /** * 文件压缩 * @param srcFile 目录或者单个文件 * @param zipFile 压缩后的ZIP文件 */ public static void doCompress(File srcFile, File zipFile) throws IOException { ZipOutputStream out = null; try { out = new ZipOutputStream(new FileOutputStream(zipFile)); doCompress(srcFile, out); } catch (Exception e) { throw e; } finally { out.close();//记得关闭资源 } } public static void doCompress(String filelName, ZipOutputStream out) throws IOException{ doCompress(new File(filelName), out); } public static void doCompress(File file, ZipOutputStream out) throws IOException{ doCompress(file, out, ""); } public static void doCompress(File inFile, ZipOutputStream out, String dir) throws IOException { if ( inFile.isDirectory() ) { File[] files = inFile.listFiles(); if (files!=null && files.length>0) { for (File file : files) { String name = inFile.getName(); if (!"".equals(dir)) { name = dir + "/" + name; } ZipUtils.doCompress(file, out, name); } } } else { ZipUtils.doZip(inFile, out, dir); } } public static void doZip(File inFile, ZipOutputStream out, String dir) throws IOException { String entryName = null; if (!"".equals(dir)) { entryName = dir + "/" + inFile.getName(); } else { entryName = inFile.getName(); } ZipEntry entry = new ZipEntry(entryName); out.putNextEntry(entry); int len = 0 ; byte[] buffer = new byte[1024]; FileInputStream fis = new FileInputStream(inFile); while ((len = fis.read(buffer)) > 0) { out.write(buffer, 0, len); out.flush(); } //out.closeEntry(); fis.close(); } public static void main(String[] args) throws IOException { doCompress("D:/java/", "D:/java.zip"); } }
其他:spring mvc 下载普通单个文件的方法:
@RequestMapping(value = "/downloadFile") @ResponseBody public void downloadFile (HttpServletResponse response) {
OutputStream os = null;
try {
os = response.getOutputStream();
File file = new File("D:/javaweb/demo.txt");
// Spring工具获取项目resources里的文件
File file2 = ResourceUtils.getFile("classpath:shell/init.sh"); if(!file.exists()){
return;
} response.reset(); response.setHeader("Content-Disposition", "attachment;filename=demo.txt"); response.setContentType("application/octet-stream; charset=utf-8"); os.write(FileUtils.readFileToByteArray(file)); } catch (Exception e) { e.printStackTrace(); }finally{ IOUtils.closeQuietly(os); } }
补充,另外一种 利用 ResponseEntity<byte[]> 实现下载单个文件的方法:
/** * Spring下载文件 * @param request * @throws IOException */ @RequestMapping(value="/download") public ResponseEntity<byte[]> download(HttpServletRequest request) throws IOException{
// 获取项目webapp目录路径下的文件 String path = request.getSession().getServletContext().getRealPath("/"); File file = new File(path+"/soft/javaweb.txt"); HttpHeaders headers = new HttpHeaders(); headers.setContentType(MediaType.APPLICATION_OCTET_STREAM); headers.setContentDispositionFormData("attachment", "javaweb.txt"); return new ResponseEntity<byte[]>(org.apache.commons.io.FileUtils.readFileToByteArray(file),headers, HttpStatus.CREATED); }
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