Java文件的读取写入

public class ReaderAndWriter {
    public static void main(String[] args) throws IOException {
        File file = new File("word.txt");
        if (!file.exists()) {
            file.createNewFile();
        }
        FileWriter fw = null;
        fw = new FileWriter(file,true);
        fw.write("wlj love rjln");
        System.out.println("成功写入");
        fw.close();
        
        FileReader fr = new FileReader(file);
        BufferedReader bufr = new BufferedReader(fr);
        String string = null;
        while ((string=bufr.readLine())!=null){
            String name1 = string.substring(0,3);
            String s = string.substring(4,8);
            String name2 = string.substring(9,12);
            System.out.println(name1);
            System.out.println(s);
            System.out.println(name2);
            System.out.println(string);
        }

        fr.close();
    }
}