Java IO流(操作基本数据类型的流对象DataStream)

DataInputStream与DataOutputStream可以用于操作基本数据类型的流对象

import java.io.*;

public class DataStreamDemo {
    public static void main(String[] args) throws IOException
    {
//        writeData();
        readData();
    }
    public static void readData() throws IOException
    {
        DataInputStream dis = new DataInputStream(new FileInputStream("data.txt"));
        int num = dis.readInt();
        boolean b = dis.readBoolean();
        double d = dis.readDouble();
        System.out.println("num="+num);
        System.out.println("b="+b);
        System.out.println("d="+d);
        dis.close();
    }
    public static void writeData() throws IOException
    {
        DataOutputStream dos = new DataOutputStream(new FileOutputStream("data.txt"));
        dos.writeInt(234);
        dos.writeBoolean(true);
        dos.writeDouble(9876.543);
        dos.close();
    }
}
//输出
num=234
b=true
d=9876.543

import java.io.*;

public class DataStreamDemo {
    public static void main(String[] args) throws IOException
    {
//        writeUTFDemo();
        readUTFDemo();
        OutputStreamWriter osw = new OutputStreamWriter(new FileOutputStream("gbk.txt"),"gbk");
        osw.write("你好");
        osw.close();
    }
    public static void writeUTFDemo() throws IOException
    {
        DataOutputStream dos = new DataOutputStream(new FileOutputStream("utfdata.txt"));
        dos.writeUTF("你好");
        dos.close();
    }
    public static void readUTFDemo() throws IOException
    {
        DataInputStream dis = new DataInputStream(new FileInputStream("utfdata.txt"));
        String s = dis.readUTF();
        System.out.println(s);
        dis.close();
    }
}
//输出
你好

Snip20191003_4.png