Advanced API (character stream & net for beginners)

Transformation flow ：

FileReader-- Character input stream （ Read ）

 FileWriter-- Character output stream （ write in ）

The basic format ：

Read ：

A character by character reading
        FileReader fr = new FileReader(file);
        int n = 0;
        while((n=fr.read())!=-1){
            System.out.println((char)n); Compared to byte stream Even one by one Can also read Chinese
        }
        fr.close();

Line by line reading ： Our chat is also sent line by line It is not a word by word transmission

        File file = new File("f:\\ picture \\6.txt");
        FileReader fr = new FileReader(file);
        BufferedReader br = new BufferedReader(fr);
        String str = null;
        while((str = br.readLine())!=null){
            System.out.println(str);
        }
        br.close();
        fr.close();

write in

Scanner mys = new Scanner(System.in);
        File file = new File("f:\\ picture \\6.txt");
        FileWriter fw = new FileWriter(file);
        BufferedWriter bw = new BufferedWriter(fw);
        while(true){
            System.out.println(" Please enter the content you want to save :");
            String str = mys.next();
            bw.write(str);
            bw.flush();// Be sure to remember to flush the buffer
            bw.newLine();// A new line
            if(str.equals("exit")){
                break;
            }
        }
        bw.close();
        fw.close();