File操作-FileReader(FileWriter)/BufferedReader(Writer)

1.FileReader/FileWriter读写文本文件

直接使用读写器进行读写。

@Test
    public void testFileReader(){
        try {
            File file = new File("test1.txt");
            File file1 = new File("test2.txt");

            FileReader fr = new FileReader(file);
            FileWriter fw = new FileWriter(file1);

            int len = 0;
            while ((len = fr.read()) !=-1) {
                System.out.println("ASCII:"+len+","+"numValue :"+(char)len);
                fw.write(len);
            }
        }   //输出ASCII与对应的字符值
}

---

2.BufferedReader/BufferedWriter文件读写与复制

在读写器外面包装了缓冲流。

@Test
    public void testBufferedReader(){
        BufferedReader br = null;
        BufferedWriter bw = null;
        try {
            File file = new File("test1.txt");
            File file1 = new File("test20.txt");

            FileReader fr = new FileReader(file);
            FileWriter fw = new FileWriter(file1);

            br = new BufferedReader(fr);
            bw = new BufferedWriter(fw);
-------------------第一种方式--------------------------          
//          char[] c = new char[1024];
//          int len;
//          while((len = br.read(c))!= -1){
//              String str = new String(c, 0, len);
//              System.out.print(str);
//          }
------------------第二种方式------------------------------
            String str;
            while((str = br.readLine()) != null){
                System.out.println(str);
                bw.write(str + "\n");
//              bw.newLine();//与上面效果相同，换行
                bw.flush();
            }
        }catch (IOException e) {
            e.printStackTrace();
        }finally{
            if(bw != null){
                try {
                    bw.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }

            }
            if(br != null){
                try {
                    br.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }

            }

        }
    }