DataInputStream, DataOutputStream
import java.io.DataInputStream; import java.io.DataOutputStream; import java.io.FileInputStream; import java.io.FileOutputStream; class DOSDISDemo { public static void main(String[] args) throws Exception { DataOutputStream dos = null; FileOutputStream fos = new FileOutputStream("data.dat"); dos = new DataOutputStream(fos); dos.writeInt(256); dos.writeDouble(Math.PI); dos.writeUTF("Java"); DataInputStream dis = null; FileInputStream fis = new FileInputStream("data.dat"); dis = new DataInputStream(fis); System.out.println(dis.readInt()); System.out.println(dis.readDouble()); System.out.println(dis.readUTF()); } }