干了这杯Java之transient关键字

看源码的时候,发现transient这个关键字,不甚理解,查找资料发现:不被序列化

疑问:

• 静态变量是不是不被序列化？

public class User implements Serializable {

	private static final long serialVersionUID = 2877054094045568710L;

	private String username;

	private transient String password;

	private static int age;

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getPassword() {
		return password;
	}

	public void setPassword(String password) {
		this.password = password;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		User.age = age;
	}

	public static void main(String[] args) {
		User user = new User();
		user.setUsername("imeng");
		user.setPassword("123456");
		user.setAge(22);

		try {
			ObjectOutputStream os = new ObjectOutputStream(
			        new FileOutputStream("/Users/imeng/Desktop/user.txt"));
			os.writeObject(user);
			os.close();
		} catch (IOException e) {
			e.printStackTrace();
		}

		//序列号后改变Static的值
		user.setAge(100);

		ObjectInputStream oi;
		try {
			oi = new ObjectInputStream(new FileInputStream("/Users/imeng/Desktop/user.txt"));
			User readUser = (User) oi.readObject();
			System.out.println("username:" + readUser.getUsername());
			System.out.println("transient关键字password:" + readUser.getPassword());
			System.out.println("静态变量age:" + readUser.getAge());
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}
}

username:imeng
password:null
age:100

结论:

• transient关键字可以阻止序列化
• 序列号并不保存静态变量