IO流——内存流

内存流：ByteArrayInputStream、ByteArrayOutputStream、CharArrayInputStream、CharOutputStream、StringReader、StringWriter

目的：将数据临时存放在数组中（相当于内存中）。

tips：
上面的Writer、outputStream：write方法是将数据从程序写入内存
上面的Reader、inputStream：read方法是从内存读取数据到程序

示例代码：

public class TestNercunStream {

    public static void main(String[] args) throws IOException {
//        testByteArrayStream();
//        testCharArrayWriterAndReader();
        testStringReaderAndWriter();
    }

    public static void testByteArrayStream() throws IOException {
        /*字节流不适合处理中文*/
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        bos.write("I'm legend".getBytes());
        System.out.println("bos将数据写入内存");
        byte[] data = bos.toByteArray();

        System.out.println("从内存中读入程序");
        ByteArrayInputStream bis = new ByteArrayInputStream(data);
        int len;
        byte[] result = new byte[11];
        while((len = bis.read(result))!=-1){
            System.out.println(new String(result,0,len));
        }

        bos.close();
        bis.close();
    }

    public static void testCharArrayWriterAndReader() throws IOException {
        CharArrayWriter writer = new CharArrayWriter();
        writer.write("我是传奇".toCharArray());
        System.out.println("将中文字符写入内存");
        char[] data = writer.toCharArray();

        System.out.println("从内存中读入程序");
        CharArrayReader reader = new CharArrayReader(data);
        char[] result = new char[10];/*这里不用担心乱码，因为一个中文字符就是一个char*/
        int len;
        while((len = reader.read(result))!= -1){
            System.out.println(new String(result,0,len));
        }

        writer.close();
        reader.close();

    }

    public static void testStringReaderAndWriter() throws IOException {
        StringWriter writer = new StringWriter();
        writer.write("我是传奇");
        System.out.println("将字符串写入内存");
        String data = writer.toString();

        System.out.println("从内存中读入程序");
        StringReader reader = new StringReader(data);
        char[] result = new char[10];
        int len;
        while((len = reader.read(result))!=-1){
            System.out.println(new String(result,0,len));
        }
        writer.close();
        reader.close();
    }

}

猜你喜欢