节点流：

字节数组输入流 ByteArrayInputStream

字节数组输出流 ByteArrayOutputStream

将字节数组转化成流

ByteArrayInputStream(byte [] )

不用关闭

toByteArray() 输出到字节数组

处理流

输入流：DataInputStream(InputStream x) readXXX()

输出流：DataOutputStream(OutputStream x) writeXXX()

// DataInputStream/DataOutputStream 写入到文件/从文件读取    public static void main (String [] args) throws IOException{        File file = new File("D:/桌面/DataInputStream.txt");        DataInputStream input = new DataInputStream(new FileInputStream(file));//      DataOutputStream output = new DataOutputStream(new FileOutputStream(file));        int a = 100;        double b = 200;        String c = "string";//      output.writeInt(a);//      output.writeDouble(b);//      output.writeUTF(c);        int d = input.readInt();        double e = input.readDouble();        String f = input.readUTF();        System.out.println(d);        System.out.println(e);        System.out.println(f);//      output.close();//      input.close();    }

对象序列化：

ObjectInputStream -> readObject()

ObjectOutputStream -> writeObject() 先序列化后反序列化,对象必须使用java.io.Seriallizable接口 不是所有属性都需要序列化，用transient表示不需要序列化的属性

可变参数只能放在新蔡的最后一个位置（Closeable …）

…可变参数，处理方式与数组一致

try- with-resource

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打印流和输入流

system.out

system.in printStream

PrintStream ps = System.outps.println();

ps = new PrintStream(new BufferedOutputStream(new FileOutputStream(src)))ps.println(); //输出到文件

System.out

System.err

System.in 键盘输入

PrintStream output = new PrintStream(new FileOutputStream(new File("D:/桌面/2.txt")));output.print("printStream");

InputStream in = System.in;//system.in 实际上是一个InputStream流

重定向

setIn()

setOut() setErr()

System.setOut(new PrintStream(new FileOutputStream(“”)));

System.out.println(“2333”);

System.setOut(new PrintStream(new FileOutputStream(new FileDescripter.out)));//返回控制台

System.setOut(new PrintStream(new FileOutputStream("D:/桌面/3.txt")));System.out.println("重定向");