java读取文件和写入文件

//读取
 public static String readFile(String fileUrl) throws IOException {
        FileInputStream fis=new FileInputStream(str);
        InputStreamReader isr=new InputStreamReader(fis, "GBK");//utf-8 或者gbk  根据你个人需求
        BufferedReader br = new BufferedReader(isr);
        //简写如下
        //BufferedReader br = new BufferedReader(new InputStreamReader(
        //        new FileInputStream("E:/phsftp/evdokey/evdokey_201103221556.txt"), "UTF-8"));
        String line="";
        String arrs="";
        while ((line=br.readLine())!=null) {
            arrs += line+",";
            
        }
        br.close();
        isr.close();
        fis.close();
        return arrs;//返回的字符串 可以 split（“，”） 来分割为数组
    }
//以字符串数组形式写入
 public static void writeFile(String []arrs) throws IOException {
      
        
        FileOutputStream fos=new FileOutputStream(new File("C:/Users......"));
        OutputStreamWriter osw=new OutputStreamWriter(fos, "GBK");
        BufferedWriter  bw=new BufferedWriter(osw);
        //简写如下：
        //BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(
        //        new FileOutputStream(new File("E:/phsftp/evdokey/evdokey_201103221556.txt")), "UTF-8"));

        for(String arr:arrs){
            bw.write(arr+"\t\n");
        }
        
        //注意关闭的先后顺序，先打开的后关闭，后打开的先关闭
        bw.close();
        osw.close();
        fos.close();
    }