class&object

类(class)是构造对象的模板或蓝图。

对象的行为是用可调用的方法定义的.

import java.time.*;

public class EmployeeTest{
    public static void main(String[] args){

    }
}

class Employee{
    // instance fields --------> object's state
    private String name;
    private double salary;
    private LocalDate hireDay;

    // constructors -------> create object
    public Employee(String name, double salary, int year, int month, int day){
        this.name = name;
        this.salary = salary;
        hireDay = LocalDate.of(year, month, day);
    }

    // methods ----> object's behavior
    public String getName(){
        return name;
    }

    public double getSalary(){
        return salary;
    }

    public LocalDate getHireDay(){
        return hireDay;
    }

}