java—封装

java—封装

封装：把对象的属性和行为结合成一个单独的单位，并尽可能的隐藏对象的内部细节（数据），外部不能直接访问，只能根据有限的对外接口与其发生联系。

也就是说，程序猿A写了一大堆代码但我不想知道细节，只需知道如何调用就好了

public class User {
	private int userId;//用户ID
	private String userName;//用户名
	private String sex;//性别
	private int age;//年龄
	private String phoneNumber;//电话

	//无参构造方法，构造方法用于外部创建对象访问
	public User() {

	}
//有参构造方法
	public User(int userId, String userName, String sex, int age, String phoneNumber) {
		super();
		this.userId = userId;
		this.userName = userName;
		this.sex = sex;
		this.age = age;
		this.phoneNumber = phoneNumber;
	}
//生成的get&set方法
	public int getUserId() {
		return userId;
	}

	public void setUserId(int userId) {
		this.userId = userId;
	}

	public String getUserName() {
		return userName;
	}

	public void setUserName(String userName) {
		this.userName = userName;
	}

	public String getSex() {
		return sex;
	}

	public void setSex(String sex) {
		this.sex = sex;
	}

	public int getAge() {
		return age;
	}

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

	public String getPhoneNumber() {
		return phoneNumber;
	}

	public void setPhoneNumber(String phoneNumber) {
		this.phoneNumber = phoneNumber;
	}

}

public class Test{
	public static void main(String[] args) {
		User user = new User();
		user.setUserId(1001);
		user.setUserName("Alice");
		user.setSex("女");
		user.setAge(18);
		user.setPhoneNumber("13254568441");
		System.out.println("id:" + user.getUserId());
		System.out.println("name:" + user.getUserName());
		System.out.println("sex:" + user.getSex());
		System.out.println("age:" + user.getAge());
		System.out.println("phoneNumber" + user.getPhoneNumber());
	}
}