java小知识1(多态中调用成员方法和变量的区别)
多态中调用成员方法和变量的区别:public class Test { public static void main(String[] args) { Animal a=new Dog(); //调用成员变量:编译看左边,运行看左边 //如果左边的类中没有,就会向上找,直到找到为止 //如果没有找到,就会报错 System.out.println(a.name);//动物 //调用成员方法:编译看左边,运行看右边 //如果左边的类中没有,就会向上找,直到找到为止 //如果没有找到,就会报错 //但是运行时调用的是右边的方法 a.show();//Dog—show }}class Animal{ String...
Hello World
Welcome to Hexo! This is your very first post. Check documentation for more info. If you get any problems when using Hexo, you can find the answer in troubleshooting or you can ask me on GitHub. Quick StartCreate a new post1$ hexo new "My New Post" More info: Writing Run server1$ hexo server More info: Server Generate static files1$ hexo generate More info: Generating Deploy to remote sites1$ hexo deploy More info: Deployment
java小知识
子类可以调用本类的有参构造父类的构造方法不能调用要用super();set和get方法不属于构造方法,可以调用
小项目1
public class User { private String username; private String password; private String id; private String phoneNumber; public User() { } public User(String username, String password, String id, String phoneNumber) { this.username = username; this.password = password; this.id = id; this.phoneNumber = phoneNumber; } public String getUsername() { return username; } public void setUsername(String username) { this.username =...
文章标题
cc
