java：I/O 一行一行读取和写入

BufferedReader逐行读取

import java.io.*;

class Test

{

    public static void main(String args []){

        FileReader reader =null;

        BufferedReader bufferedReader =null;

        try{

        reader = new FileReader("e://d/from.txt");

        bufferedReader = new BufferedReader(reader);

        String line =null;

        while(true){

            line =bufferedReader.readLine();

            if(line ==null){

                break;

            }

            System.out.println(line);

        }

}catch(Exception e){

            System.out.println(e);

        }

        finally{

            try{

                bufferedReader.close();

                reader.close();
}catch(Exception e){

                System.out.println(e);

            }

        }

    }

}

BufferedWriter逐行写入

import java.io.*;

class Test

{

    public static void main(String [] args){

        FileWriter fw =null;

        BufferedWriter bw =null;

        String [] arrs = {

            "zhang,33",

            "li,44"

            };

            try{

                fw = new FileWriter("e://d/from.txt");

                bw = new BufferedWriter(fw);

for(String arr:arrs){

                     bw.write(arr+"\t\n");

                }

                /*等效于

                for(int i=0;i<arrs.length;i++){

                    bw.write(arrs[i]+"\t\n");

                }

                */
}catch(Exception e){

                System.out.println(e);

            }

            finally{

                try{

                    bw.close();

                    fw.close();
}catch(Exception e){

                    System.out.println(e);

                }

            }

    }

}

java：I/O 一行一行读取和写入