1、数据流

package DataTest_8;

import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;

public class Test {
	public static void main(String[] args) throws IOException {
		ByteArrayOutputStream baos= new ByteArrayOutputStream();
		DataOutputStream dos = new DataOutputStream(new BufferedOutputStream(baos));
		try {
			dos.writeUTF("测试");
			dos.writeInt(20);
			dos.writeBoolean(true);
			dos.flush();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		byte[] b = baos.toByteArray();
		DataInputStream dis = new DataInputStream(new ByteArrayInputStream(b));
		String s = dis.readUTF();
		int age = dis.readInt();
		boolean tr = dis.readBoolean();
		System.out.println(tr);
	}
}

2、对象流

package ObjectTest_9;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;

public class Test2 {
	public static void main(String[] args) throws IOException, ClassNotFoundException {
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		ObjectOutputStream oos = new ObjectOutputStream(new BufferedOutputStream(baos));
		oos.writeUTF("测试");
		oos.writeInt(20);
		oos.writeObject("哈哈哈");
		oos.writeObject(new A("张三",20));
		oos.flush();
		byte[] b = baos.toByteArray(); 
		ObjectInputStream ois = new ObjectInputStream(new BufferedInputStream(new ByteArrayInputStream(b)));
		ois.readUTF();
		ois.readInt();
		Object o1 = ois.readObject();
		Object o2 = ois.readObject();
		if(o1 instanceof String) {
			System.out.println((String)o1);
		}
		if(o2 instanceof A) {
			A a = (A)o2;
			System.out.println(a.getName());
			System.out.println(a.getAge());
		}
	}
}
class A implements java.io.Serializable{
	private String name;
	private int age;
	A(){
	}
	A(String name,int age){
		this.name = name;
		this.age = age;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
}

3、打印流

package IOTest_10;

import java.io.BufferedOutputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.PrintStream;

public class Test1 {
	public static void main(String[] args) {
		PrintStream ps = System.out;
		ps.println("测试");
		ps.println(true);
		try {
			ps = new PrintStream(new BufferedOutputStream(new FileOutputStream("测试.txt")));
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		ps.println("a");
		ps.println("b");
		ps.println("c");
		ps.println("d");
		ps.flush();
		ps.close();
		ps = System.out;
		ps.print("aa");
	}
}