IO流13 --- 转换流实现文件复制 --- 技术搬运工（尚硅谷）

InputStreamReader 将字节输入流转换为字符输入流

OutputStreamWriter 将字符输出流转换为字节输出流

@Test
public void test2() {
    //转换流
    InputStreamReader isr = null;
    OutputStreamWriter osw = null;
    
    try {
        //节点流
        FileInputStream fis = new FileInputStream("水浒传.txt");
        FileOutputStream fos = new FileOutputStream("水浒传_gbk.txt");
        //转换流
           isr = new InputStreamReader(fis, "utf-8");
        osw = new OutputStreamWriter(fos, "gbk");
        //复制文件
        char[] cbuf = new char[20];
        int len;
        while ((len = isr.read(cbuf)) != -1) {
            osw.write(cbuf, 0, len);
        } 
        System.out.println("复制成功");
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if(osw != null) {
            try {
                osw.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        if(isr != null) {
            try {
                isr.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}