一，IO流-数据流

二，数据输出流

 

 三，案例

package BigDecimal;

import java.io.DataOutputStream;
import java.io.FileOutputStream;

public class DATaOutputStreamss {
    public static void main(String[] args)  {
        try ( //1,创建一个数据输出流包装低级的字节输出流
              DataOutputStream ds =
                      new DataOutputStream
                              (new FileOutputStream("untitled\\src\\BigDecimal\\Duxiaonanj.txt"));
              ){
            ds.write(5);
            ds.writeDouble(99.5);
            ds.writeBoolean(true);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

四，数据输入流

五，案例

package BigDecimal;

import java.io.DataInputStream;
import java.io.FileInputStream;

public class DATaInputStreamss {
    public static void main(String[] args) {
        try( DataInputStream ds =new DataInputStream(new FileInputStream("C:\\untitled1\\untitled\\src\\BigDecimal\\Duxiaonanj.txt"))
        ;){
            int i =ds.readInt();
            System.out.println(i);

            double d =ds.readDouble();
            System.out.println(d);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}