Java IO- 转换流

Posted 2020-07-24

转换流

InputStreamReader和OutputStreamWriter用于字节数据到字符数据之间的转换。

InputStreamReader需要和InputStream套接（把InputStream转换成InputStreamReader）

OutputStreamWriter需要和OutputStream套接（把OutputStreamWriter转换成OutputStream）

转换流在构造时可以指定其编码集合，例如：

InputStream is = new InputStreamReader(System.in, "ios8859_1")；

例子一、

    public static void main(String[] args) {
        try {
            OutputStreamWriter osw = new OutputStreamWriter(new FileOutputStream("d:\\bak\\char.txt"));
            osw.write("miscalkjsdlasjdlajslkdalksd");
            System.out.println(osw.getEncoding());
            osw.close();
            
            osw = new OutputStreamWriter(new FileOutputStream("d:\\bak\\char.txt", true), "ISO8859_1");//true，追加
            osw.write("sadasdasdasdasd");
            System.out.println(osw.getEncoding());
            osw.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        
    }

结果：

UTF8//系统默认的编码
ISO8859_1

例子二、

    public static void main(String[] args) {
        try {
            InputStreamReader isr = new InputStreamReader(System.in);
            BufferedReader br = new BufferedReader(isr);
            String s = null;
            s = br.readLine();
            while(s != null) {
                if("exit".equalsIgnoreCase(s))
                    break;
                System.out.println(s.toUpperCase());
                s = br.readLine();
            }
            br.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

结果：

add111
ADD111
exit