文件下载Controller,文件夹内容监听，文件上传，运行程序通过url实现文件下载

文件下载Controller

@RequestMapping("/fileDownLoad")
 public ResponseEntity<byte[]> fileDownLoad(HttpServletRequest request) throws Exception{
  
   String downloadFilePath="D:\\Data\\Download";//从我们的上传文件夹中去取
         String filename = "SocketClient-Android-Of-Final-Assignment.apk";
         File file = new File(downloadFilePath+File.separator+filename);//新建一个文件
        
         HttpHeaders headers = new HttpHeaders();//http头信息
        
         String downloadFileName = new String(filename.getBytes("UTF-8"),"iso-8859-1");//设置编码
        
         headers.setContentDispositionFormData("attachment", downloadFileName);
        
         headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
        
         //MediaType:互联网媒介类型  contentType：具体请求中的媒体类型信息
        
         return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),headers,HttpStatus.CREATED);
        
 }

文件夹内容监听和文件上传

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

import org.apache.commons.io.filefilter.FileFilterUtils;
import org.apache.commons.io.monitor.FileAlterationListener;
import org.apache.commons.io.monitor.FileAlterationMonitor;
import org.apache.commons.io.monitor.FileAlterationObserver;

public class FileListener {

    public static void main(String[] args) throws Exception {

        File directory = new File("H:/test");
        // 轮询间隔 5 秒
        long interval = TimeUnit.SECONDS.toMillis(5);
        // 创建一个文件观察器用于处理文件的格式
        FileAlterationObserver observer = new FileAlterationObserver(directory, FileFilterUtils.and(
        FileFilterUtils.fileFileFilter(),FileFilterUtils.suffixFileFilter(".txt")));
        //设置文件变化监听器
        observer.addListener(new MyFileListener());
        FileAlterationMonitor monitor = new FileAlterationMonitor(interval,observer);
        monitor.start();

    }
   

}
final class MyFileListener implements FileAlterationListener{

    @Override
    public void onDirectoryChange(File arg0) {

        System.out.println("文件目录发生改变！！！");
       
    }

    @Override
    public void onDirectoryCreate(File arg0) {

        System.out.println("文件目录创建成功！！！");

    }

    @Override
    public void onDirectoryDelete(File arg0) {

        System.out.println("文件目录已经删除！！！");
       
    }

    @Override
    public void onFileChange(File arg0) {

        System.out.println("文件发生改变！！！");
       
    }

    @Override
    public void onFileCreate(File arg0) {

     File arg1=arg0;
     System.out.println(arg1);
      InputStream in = null;
         OutputStream out = null;
     try {
 
        String srcPath = arg0.toString();
        File parentDir = new File("\\\\192.168.1.104\\test");
        File targetPath = new File(parentDir,   srcPath.substring(srcPath.lastIndexOf("\\")));
        in = new FileInputStream(srcPath);
         out = new FileOutputStream(targetPath);
     
       
            byte[] bs = new byte[1024];
            int len = -1;
            while((len = in.read(bs)) != -1) {
                out.write(bs, 0, len);
            }}catch(Exception e){
          e.printStackTrace();
         }
         
        finally {
            try {
                out.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
            try {
                in.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        System.out.println("上传成功！！");
        System.out.println("文件创建成功！！！");
       
    }

    @Override
    public void onFileDelete(File arg0) {

        System.out.println("文件删除成功！！！");
       
    }

    @Override
    public void onStart(FileAlterationObserver arg0) {

        System.out.println("开始！！！");
       
    }

    @Override
    public void onStop(FileAlterationObserver arg0) {

        System.out.println("停止！！！");
       
    }
   
}

运行程序通过url实现文件下载

public static void downloadHttpUrl(String url, String dir, String fileName) {

  try {

   URL httpurl = new URL(url);

   File dirfile = new File(dir); 

         if (!dirfile.exists()) { 

          dirfile.mkdirs();

         }

   FileUtils.copyURLToFile(httpurl, new File(dir+fileName));

  } catch (Exception e) {

   e.printStackTrace();

  }

 }