Java 按行读取文件内容_line = in.readline(); while( ② )-优快云博客

本文详细介绍了如何使用Java进行文件读写操作，包括创建BufferedReader和BufferedWriter实例，读取文件内容并将其写入指定路径，以及处理异常情况和资源关闭。

（一）

String readPath = "";
  String writePath = "";

  BufferedReader in = null;
  BufferedWriter os = null;

  try {
   // 读取文件（readPaht）内容
   if(null != in){
    in.close();
   }
   in = new BufferedReader(new InputStreamReader(new FileInputStream(readPath)));
   //
   if(null != os){
    os.close();
   }
   os = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(writePath)));
   String line = in.readLine();

   while (null != line && !"".equals(line)) {
    os.write(line);
    os.newLine();
    line = in.readLine();
   }

  } catch (Exception e) {
   e.printStackTrace();
  } finally {
   try{
    if(null != in){
     in.close();
    }
    if(null != os){
     os.close();
    }
   }catch (Exception e) {
    e.printStackTrace();
   }
  }

（二）

BufferedReader   in   =   new   BufferedReader(new   FileReader("D://bug.txt"));
        String   line   =   null;

       List<String> list = new ArrayList<String>();
        while((line   =   in.readLine())!=null)
        {
            //System.out.println(line);
            list.add(line);
        }
        for(String temp: list){
        System.out.println(temp);
        }