java基础之io流总结四：字符流读写

字符流读写只适用于字符文件。

基本字符流（转换流）读写文件

转换流本身是字符流，但是实例化的时候传进去的是一个字节流，所以叫做转换流

        InputStreamReader isr = new InputStreamReader(new FileInputStream(inputPath), "GB2312");
        OutputStreamWriter osr = new OutputStreamWriter(new FileOutputStream(outPutPath), "GB2312");
        // 可以直接写入字符串/字符/字符数组等
        osr.write("xxxxx
");

        // 单个字符读写
        int c;
        while ((c = isr.read()) != -1) {
            osr.write(c);
        }

        // 字符数组读写
        char[] chs = new char[1024];
        int len;
        while ((len = isr.read(chs)) != -1) {
            osr.write(chs, 0, len);
        }

        osr.close();
        isr.close();

简化版字符流（常用）读写文件

        FileReader fr = new FileReader(inPutPath);
        FileWriter fw = new FileWriter(outPutPath);

        // 一次读写一个字符
        int ch;
        while ((ch = fr.read()) != -1) {
            fw.write(ch);
        }
        // 一次读写一个字符数组
        char[] chs = new char[1024];
        int len;
        while ((len = fr.read(chs)) != -1) {
            fw.write(chs, 0, len);
        }
        fr.close();
        fw.close();

缓冲区字符流读写文件

        BufferedReader br = new BufferedReader(new FileReader(inPutPath));
        BufferedWriter bw = new BufferedWriter(new FileWriter(outPutPath));
        // 一次读写一个字符
        int ch;
        while ((ch = br.read()) != -1) {
            bw.write(ch);
        }
        // 一次读写一个字符数组
        char[] chs = new char[1024];
        int len;
        while ((len = br.read(chs)) != -1) {
            bw.write(chs, 0, len);
            bw.newLine();
            System.out.print(new String(chs, 0, len));
        }
        // 一次读写一行数据
        String line;
        while ((line = br.readLine()) != null) {
            bw.write(line);
            bw.newLine();
            bw.flush();//刷新数据
        }
        br.close();
        bw.close();