201771010108-韩腊梅-第七周学习总结(代码片段)

/**
 * This program demonstrates the equals method.
 * @version 1.12 2012-01-26
 * @author Cay Horstmann
 */
public class EqualsTest

   public static void main(String[] args)
   
      Employee alice1 = new Employee("Alice Adams", 75000, 1987, 12, 15);
      Employee alice2 = alice1;
      Employee alice3 = new Employee("Alice Adams", 75000, 1987, 12, 15);
      Employee bob = new Employee("Bob Brandson", 50000, 1989, 10, 1);

      System.out.println("alice1 == alice2: " + (alice1 == alice2));

      System.out.println("alice1 == alice3: " + (alice1 == alice3));

      System.out.println("alice1.equals(alice3): " + alice1.equals(alice3));

      System.out.println("alice1.equals(bob): " + alice1.equals(bob));

      System.out.println("bob.toString(): " + bob);

      Manager carl = new Manager("Carl Cracker", 80000, 1987, 12, 15);
      Manager boss = new Manager("Carl Cracker", 80000, 1987, 12, 15);
      boss.setBonus(5000);//在子类中Bouns赋初值为空，主类中用更改器更改为5000
      System.out.println("boss.toString(): " + boss);
      System.out.println("carl.equals(boss): " + carl.equals(boss));
      System.out.println("alice1.hashCode(): " + alice1.hashCode());
      System.out.println("alice3.hashCode(): " + alice3.hashCode());
      System.out.println("bob.hashCode(): " + bob.hashCode());
      System.out.println("carl.hashCode(): " + carl.hashCode());
   

import java.time.*;
import java.util.Objects;

public class Employee

   private String name;
   private double salary;
   private LocalDate hireDay;
   //创建三个私有属性
   public Employee(String name, double salary, int year, int month, int day)
   
      this.name = name;
      this.salary = salary;
      hireDay = LocalDate.of(year, month, day);
   

   public String getName()
   
      return name;
   

   public double getSalary()
   
      return salary;
   

   public LocalDate getHireDay()
   
      return hireDay;
   
   public void raiseSalary(double byPercent)
   
      double raise = salary * byPercent / 100;
      salary += raise;
   //定义两个局部变量

   public boolean equals(Object otherObject)
   
      //快速测试几个类的根是否相同，即是否是同一个超类。
      if (this == otherObject) return true;
      if (otherObject == null) return false;

      //用getclass（）方法得到对象的类。如果几个类不匹配，则它们不相等
      if (getClass() != otherObject.getClass()) return false;
      Employee other = (Employee) otherObject;
      //测试字段是否具有相同的值
      return Objects.equals(name, other.name) && salary == other.salary && Objects.equals(hireDay, other.hireDay);
   
    public int hashCode()//重写hashcode方法，使相等的两个对象获取的HashCode也相等
   
      return Objects.hash(name, salary, hireDay); 
   

   public String toString()
   
      return getClass().getName() + "[name=" + name + ",salary=" + salary + ",hireDay=" + hireDay
            + "]";
   

public class Manager extends Employee

   private double bonus;

   public Manager(String name, double salary, int year, int month, int day)
   
      super(name, salary, year, month, day);
      bonus = 0;
   

   public double getSalary()
   
      double baseSalary = super.getSalary();
      return baseSalary + bonus;
   

   public void setBonus(double bonus)
   
      this.bonus = bonus;
   

   public boolean equals(Object otherObject)////快速测试几个类的根是否相同，即是否是同一个超类
   
      if (!super.equals(otherObject)) return false;
      Manager other = (Manager) otherObject;
       //使用super.equals检查这个类和其他是否属于同一个类
      return bonus == other.bonus;
   

   public int hashCode()
   
      return java.util.Objects.hash(super.hashCode(), bonus);
   

   public String toString()
   
      return super.toString() + "[bonus=" + bonus + "]";
   

import java.util.*;

/**
 * This program demonstrates the ArrayList class.
 * @version 1.11 2012-01-26
 * @author Cay Horstmann
 */
public class ArrayListTest

   public static void main(String[] args)
   
      //用三个Employee类填充staff数组列表
      ArrayList<Employee> staff = new ArrayList<>();//动态数组
      staff.add(new Employee("Carl Cracker", 75000, 1987, 12, 15));
      staff.add(new Employee("Harry Hacker", 50000, 1989, 10, 1));
      staff.add(new Employee("Tony Tester", 40000, 1990, 3, 15));

      //将每个人的薪水提高5%
      for (Employee e : staff)
         e.raiseSalary(5);

      //打印出所有Employee类的信息
      for (Employee e : staff)
         System.out.println("name=" + e.getName() + ",salary=" + e.getSalary() + ",hireDay="
               + e.getHireDay());
   

import java.time.*;

public class Employee

   private String name;
   private double salary;
   private LocalDate hireDay;
   //创建三个私有属性
   public Employee(String name, double salary, int year, int month, int day)
   
      this.name = name;
      this.salary = salary;
      hireDay = LocalDate.of(year, month, day);
   

   public String getName()
   
      return name;
   

   public double getSalary()
   
      return salary;
   

   public LocalDate getHireDay()
   
      return hireDay;
   
   public void raiseSalary(double byPercent)
   
      double raise = salary * byPercent / 100;
      salary += raise;
   //定义两个局部变量

import java.util.*;

/**
 * This program demonstrates enumerated types.
 * @version 1.0 2004-05-24
 * @author Cay Horstmann
 */
public class EnumTest
  
   public static void main(String[] args)
     
      Scanner in = new Scanner(System.in);
      System.out.print("Enter a size: (SMALL, MEDIUM, LARGE, EXTRA_LARGE) ");
      String input = in.next().toUpperCase();//字符串转换为大写
      Size size = Enum.valueOf(Size.class, input);
      System.out.println("size=" + size);
      System.out.println("abbreviation=" + size.getAbbreviation());
      if (size == Size.EXTRA_LARGE)
         System.out.println("Good job--you paid attention to the _.");      
   


enum Size//枚举类型

   SMALL("S"), MEDIUM("M"), LARGE("L"), EXTRA_LARGE("XL");

   private Size(String abbreviation)  this.abbreviation = abbreviation; 
   public String getAbbreviation()  return abbreviation; 

   private String abbreviation;