生成UUID

    UUID uuid=UUID.randomUUID();
    System.out.println("uuid======"+uuid);

文件上传下载

package com.imt.sys.util;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.UUID;

import org.junit.Test;
import org.springframework.test.context.TestExecutionListeners;

public class uploadText {
    private   String file = "";
    //保存字符串到文件中
    public void saveAsFileWriter(String content,UUID uuid) {
     file="F:/text/"+uuid+".txt";
     FileWriter fwriter = null;
     try {
      fwriter = new FileWriter(file);
      fwriter.write(content);
     } catch (IOException ex) {
      ex.printStackTrace();
     } finally {
      try {
       fwriter.flush();
       fwriter.close();
      } catch (IOException ex) {
       ex.printStackTrace();
      }
     }
    }
        //读取本地文本
       public  String readFileByLines(UUID uuid) {
            File file = new File("F:/text/"+uuid+".txt");
            BufferedReader reader = null;
            String content="";
            try {
                System.out.println("以行为单位读取文件内容，一次读一整行：");
                reader = new BufferedReader(new FileReader(file));
                String tempString = null;
                int line = 1;
                // 一次读入一行，直到读入null为文件结束
                while ((tempString = reader.readLine()) != null) {
               //加上p标签 ，前台显示可以换行 
               tempString="<p>"+tempString+"</p>";
                // 显示行号
                                    System.out.println("line?????????????????????????????????? " + line + ": " + tempString);
                    content=tempString;
                    line++;
                }
            }catch(IOException e){

            }
            return content;
       }
}