DataOutputStream 和 ObjectOutputStream的共同点是：

1、写出后读取

2、读取顺序和写出一致

数据流操作：

// 写入

		ByteArrayOutputStream baos = new ByteArrayOutputStream();

		DataOutputStream dos = new DataOutputStream(new BufferedOutputStream(baos));

		dos.writeUTF("编码辛酸泪");

		dos.writeInt(18);

		dos.writeBoolean(false);

		dos.writeChar('a');

		dos.flush();

		byte[] datas = baos.toByteArray();

		System.out.println(datas.length);

		// 写出

		ByteArrayInputStream bais = new ByteArrayInputStream(datas);

		DataInputStream dis = new DataInputStream(new BufferedInputStream(bais));

		String msg = dis.readUTF();

		int age = dis.readInt();

		boolean flag = dis.readBoolean();

		char ch = dis.readChar();

		System.out.println(ch);

对象流操作：

对象的写入写入又叫序列化和方序列化，需要注意的是，并不是所有的对象都可以序列化，如果要对对象进行序列化，需要实现 Serializable 接口，如果不想让对象中某个属性序列化，可以使用 transient 关键字标识

比如我们自己定义一个类：

class Employee implements Serializable{

	private transient String name;

	private double salary;

	public Employee() {

	}

	public Employee(String name, double salary) {

		super();

		this.name = name;

		this.salary = salary;

	}

	public String getName() {

		return name;

	}

	public void setName(String name) {

		this.name = name;

	}

	public double getSalary() {

		return salary;

	}

	public void setSalary(double salary) {

		this.salary = salary;

	}

}

序列化到字节数组：

// 写出--> 序列化

		ByteArrayOutputStream baos = new ByteArrayOutputStream();

		ObjectOutputStream oos = new ObjectOutputStream(new BufferedOutputStream(baos));

		// 操作数据类型

		oos.writeUTF("编码辛酸泪");

		oos.writeInt(18);

		oos.writeBoolean(false);

		oos.writeChar('a');

		// 操作对象

		oos.writeObject("谁解其中味");

		oos.writeObject(new Date());

		oos.writeObject(new Employee("马云", 400));

		oos.flush();

		byte[] datas = baos.toByteArray();

		oos.close();

		// 读取--> 反序列化

		ByteArrayInputStream bais = new ByteArrayInputStream(datas);

		ObjectInputStream ois = new ObjectInputStream(new BufferedInputStream(bais));

		String msg = ois.readUTF();

		int age = ois.readInt();

		boolean flag = ois.readBoolean();

		char ch = ois.readChar();

		System.out.println(age);

		// 对象还原

		Object str = ois.readObject();

		Object date = ois.readObject();

		Object emp = ois.readObject();

		if(str instanceof String) {

			String strObj = (String) str;

			System.out.println(strObj);

		}

		if(date instanceof Date) {

			Date dateObj = (Date) date;

			System.out.println(dateObj);

		}

		if(emp instanceof Employee) {

			Employee empObj = (Employee) emp;

			System.out.println(empObj.getName() + "-->" + empObj.getSalary());

		}

		ois.close();

	}

序列化到文件：

// 写出--> 序列化

		ObjectOutputStream oos = new ObjectOutputStream(

				new BufferedOutputStream(new FileOutputStream("obj.ser")));

		// 操作数据类型

		oos.writeUTF("编码辛酸泪");

		oos.writeInt(18);

		oos.writeBoolean(false);

		oos.writeChar('a');

		// 操作对象

		oos.writeObject("谁解其中味");

		oos.writeObject(new Date());

		oos.writeObject(new Employee("马云", 400));

		oos.flush();

		oos.close();

		// 读取--> 反序列化

		ObjectInputStream ois = new ObjectInputStream(

				new BufferedInputStream(new FileInputStream("obj.ser")));

		String msg = ois.readUTF();

		int age = ois.readInt();

		boolean flag = ois.readBoolean();

		char ch = ois.readChar();

		System.out.println(age);

		// 对象还原

		Object str = ois.readObject();

		Object date = ois.readObject();

		Object emp = ois.readObject();

		if(str instanceof String) {

			String strObj = (String) str;

			System.out.println(strObj);

		}

		if(date instanceof Date) {

			Date dateObj = (Date) date;

			System.out.println(dateObj);

		}

		if(emp instanceof Employee) {

			Employee empObj = (Employee) emp;

			System.out.println(empObj.getName() + "-->" + empObj.getSalary());

		}

		ois.close();