JAVA 文件压缩（IO/NIO）

w_十二2024-08-29 22:16

IO

java 复制代码

 @GetMapping("io")
  public void downloadZip() {
    long start = System.currentTimeMillis();
    EntityWrapper<AttachmentEntity> wrapper = new EntityWrapper<>();
    List<AttachmentEntity> attachments = attachmentMapper.selectList(wrapper);
    String zpiName = "D:/data/压缩文件io.zip";
    try (FileOutputStream fos = new FileOutputStream(
        zpiName); ZipOutputStream zipOutputStream = new ZipOutputStream(fos)) {
      int i = 0;
      for (AttachmentEntity attachment : attachments) {
        String uuid = UUID.randomUUID().toString();
        FileInputStream fileInputStream = new FileInputStream(attachment.getPath());
        zipOutputStream.putNextEntry(new ZipEntry(uuid + "/" + attachment.getName()));
        IOUtils.copy(fileInputStream, zipOutputStream);
        zipOutputStream.closeEntry();
        fileInputStream.close();
        i++;
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
    long end = System.currentTimeMillis();
    System.out.println("耗时：" + (end - start));
  }

NIO

java 复制代码

@GetMapping("nio")
  public void downloadZipNio() throws FileNotFoundException {
    long start = System.currentTimeMillis();
    EntityWrapper<AttachmentEntity> wrapper = new EntityWrapper<>();
    List<AttachmentEntity> attachments = attachmentMapper.selectList(wrapper);
    String zpiName = "D:/data/压缩文件nio.zip";
    try (FileOutputStream fos = new FileOutputStream(zpiName); 
        ZipOutputStream zos = new ZipOutputStream(fos);
        WritableByteChannel wbc = Channels.newChannel(zos)) {
      for (AttachmentEntity attachment : attachments) {
        FileInputStream fis = new FileInputStream(attachment.getPath());
        FileChannel channel = fis.getChannel();
        String uuid = UUID.randomUUID().toString();
        zos.putNextEntry(new ZipEntry(uuid + "/" + attachment.getName()));
        channel.transferTo(0, channel.size(), wbc);
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
    long end = System.currentTimeMillis();
    System.out.println("耗时：" + (end - start));
  }

运行时间对比(ms)

io	nio
375	349
350	321
340	330