part.getSubmittedFileName 文件上传

在进行文件上传的时候，

getSubmittedFileName方法没有，是jar包的问题，引入4、0以上的jar包

**
 * @program: _10_24
 * @description
 * @author: nan
 * @create: 2022-10-24 16:21
 * 返回文件的后缀
 **/
public class FileTool {
    public static String  getFile(String fileName){
        StringTokenizer s=new StringTokenizer(fileName,".");
        int size = s.countTokens();//切分的个数

        if (size>1){
            for (int i=0;i<size-1;i++){
                s.nextToken();
            }
            return s.nextToken();
        }else{
            return "";
        }
    }
    public static String getRandomString(){
        return UUID.randomUUID().toString().replace("-","");
    }
}

  Part fff = req.getPart("fff");
    String fileName = fff.getSubmittedFileName();
    String file = FileTool.getFile(fileName);  //获得后缀
    String randomString = FileTool.getRandomString();//转换格式
    String name=randomString+"."+file;
    System.out.println(name); //得到文件名
    BufferedInputStream get = new BufferedInputStream(fff.getInputStream());//利用流获取到源文件
    BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream("d:\\ww\\" + name));
    int s=0;
    while ((s=get.read())!=-1){
        out.write(s);
    }
    get.close();
    out.close();
}