达拉草201771010105《面向对象程序设计（java）》第七周学习总结(代码片段)

 1 public class TEST1 
 2     private String t1 = "这是TEST1的私有属性";
 3     public String t2 = "这是TEST1的公有属性";
 4     protected String t3 = "这是TEST1受保护的属性";
 5     String t4 = "这是TEST1的默认属性";
 6     private void tese1() 
 7         System.out.println("我是TEST1用private修饰符修饰的方法");
 8     
 9     public void tese2() 
10         System.out.println("我是TEST1用public修饰符修饰的方法");
11     
12     protected void tese3() 
13         System.out.println("我是TEST1用protected修饰符修饰的方法");
14     
15     void tese4() 
16         System.out.println("我是TEST1无修饰符修饰的方法");
17     
18 

 1 public class TEST2 extends TEST1
 2     private String e1 = "这是TEST2的私有属性";
 3     public String e2 = "这是TEST2的公有属性";
 4     protected String e3 = "这是TEST2受保护的属性";
 5     String e4 = "这是TEST2的默认属性";
 6     public void demo1() 
 7         System.out.println("我是TEST2用public修饰符修饰的方法");
 8     
 9     private void demo2() 
10         System.out.println("我是TEST2用private修饰符修饰的方法");
11     
12     protected void demo3() 
13         System.out.println("我是TEST2用protected修饰符修饰的方法");
14     
15     void demo4() 
16         System.out.println("我是TEST2无修饰符修饰的方法");
17     
18 

 1 public class Main 
 2     public static void main(String[] args) 
 3         TEST2 test2 = new TEST2();
 4         /*以下设计代码分别调用 demo1 demo2 demo3 demo4 test1 test2 test3 test4方法和t1 t2 t3 t3 e1 e2 e3 e4属性，结合程序运行结果理解继承和权限修饰符的用法与区别*/
 5     test2.demo1();
 6     test2.demo3();
 7     test2.demo4();
 8     test2.tese2();
 9     test2.tese3();
10     test2.tese4();
11     System.out.println(test2.e2);
12     System.out.println(test2.e3);
13     System.out.println(test2.e4);
14     System.out.println(test2.t2);
15     System.out.println(test2.t3);
16     System.out.println(test2.t4);
17     
18 

 1 package equals;
 2 
 3 /**
 4  * This program demonstrates the equals method.
 5  * @version 1.12 2012-01-26
 6  * @author Cay Horstmann
 7  */
 8 public class EqualsTest
 9 
10    public static void main(String[] args)
11    
12       Employee alice1 = new Employee("Alice Adams", 75000, 1987, 12, 15);
13       Employee alice2 = alice1;
14       Employee alice3 = new Employee("Alice Adams", 75000, 1987, 12, 15);
15       Employee bob = new Employee("Bob Brandson", 50000, 1989, 10, 1);
16 
17       System.out.println("alice1 == alice2: " + (alice1 == alice2));
18 
19       System.out.println("alice1 == alice3: " + (alice1 == alice3));
20 
21       System.out.println("alice1.equals(alice3): " + alice1.equals(alice3));
22 
23       System.out.println("alice1.equals(bob): " + alice1.equals(bob));
24 
25       System.out.println("bob.toString(): " + bob);
26 
27       Manager carl = new Manager("Carl Cracker", 80000, 1987, 12, 15);
28       Manager boss = new Manager("Carl Cracker", 80000, 1987, 12, 15);
29       boss.setBonus(5000);
30       System.out.println("boss.toString(): " + boss);
31       System.out.println("carl.equals(boss): " + carl.equals(boss));
32       System.out.println("alice1.hashCode(): " + alice1.hashCode());
33       System.out.println("alice3.hashCode(): " + alice3.hashCode());
34       System.out.println("bob.hashCode(): " + bob.hashCode());
35       System.out.println("carl.hashCode(): " + carl.hashCode());
36    
37 

 1 package equals;
 2 
 3 import java.time.*;
 4 import java.util.Objects;
 5 
 6 public class Employee
 7 
 8    private String name;//private定义了一个只能在该类中访问的字符串变量
 9    private double salary;
10    private LocalDate hireDay;
11    //创建私有属性
12 
13    public Employee(String name, double salary, int year, int month, int day)
14    
15       this.name = name;
16       this.salary = salary;
17       hireDay = LocalDate.of(year, month, day);
18    
19 
20    public String getName()
21    
22       return name;
23    
24 
25    public double getSalary()
26    
27       return salary;
28    
29 
30    public LocalDate getHireDay()
31    
32       return hireDay;
33    
34    //访问器
35 
36    public void raiseSalary(double byPercent)
37    
38       double raise = salary * byPercent / 100;
39       salary += raise;
40    
41 
42    public boolean equals(Object otherObject)
43    
44       // 快速测试这些对象是否相同
45       if (this == otherObject) return true;
46 
47       // 如果显示参数为空，必须返回flase
48       if (otherObject == null) return false;
49 
50       // 如果几个类不匹配，则他们不相同
51       if (getClass() != otherObject.getClass()) return false;
52 
53       // 其他对象为非空Employee类
54       Employee other = (Employee) otherObject;
55 
56       // 测试是不是有相同值
57       return Objects.equals(name, other.name) && salary == other.salary && Objects.equals(hireDay, other.hireDay);
58    
59 
60    public int hashCode()
61    
62       return Objects.hash(name, salary, hireDay); 
63    
64 
65    public String toString()//把其他类型的数据转换为字符串类型的数据
66    
67       return getClass().getName() + "[name=" + name + ",salary=" + salary + ",hireDay=" + hireDay
68             + "]";
69    
70 

 1 package equals;
 2 
 3 public class Manager extends Employee//扩展了一个子类Manager
 4 
 5    private double bonus;//创建一个私有属性
 6 
 7    public Manager(String name, double salary, int year, int month, int day)//定义变量
 8    
 9       super(name, salary, year, month, day);//调用了父类的构造器
10       bonus = 0;
11    
12 
13    public double getSalary()
14    
15       double baseSalary = super.getSalary();//调用父类的方法
16       return baseSalary + bonus;
17    
18 
19    public void setBonus(double bonus)//更改器
20    
21       this.bonus = bonus;
22    
23 
24    public boolean equals(Object otherObject)
25    
26       if (!super.equals(otherObject)) return false;
27       Manager other = (Manager) otherObject;
28       // 用super.equals检查这个类和其他类是否属于同一个类
29       return bonus == other.bonus;
30    
31 
32    public int hashCode()
33    
34       return java.util.Objects.hash(super.hashCode(), bonus);
35    
36 
37    public String toString()//把其他类型的数据转换为字符串类型的数据
38    
39       return super.toString() + "[bonus=" + bonus + "]";
40    
41 

 1 package arrayList;
 2 
 3 import java.util.*;
 4 
 5 /**
 6  * This program demonstrates the ArrayList class.
 7  * @version 1.11 2012-01-26
 8  * @author Cay Horstmann
 9  */
10 public class ArrayListTest
11 
12    public static void main(String[] args)
13    
14       // 用三个Employee类填充staff数组列表
15       ArrayList<Employee> staff = new ArrayList<>();//构造了一个ArrayList数组
16 
17       staff.add(new Employee("Carl Cracker", 75000, 1987, 12, 15));
18       staff.add(new Employee("Harry Hacker", 50000, 1989, 10, 1));
19       staff.add(new Employee("Tony Tester", 40000, 1990, 3, 15));
20 
21       // raise everyone‘s salary by 5%
22       for (Employee e : staff)
23          e.raiseSalary(5);
24 
25       //打印出所有Employee类的信息
26       for (Employee e : staff)
27          System.out.println("name=" + e.getName() + ",salary=" + e.getSalary() + ",hireDay="
28                + e.getHireDay());
29    
30 

 1 package arrayList;
 2 
 3 import java.time.*;
 4 
 5 public class Employee
 6 
 7    private String name;
 8    private double salary;
 9    private LocalDate hireDay;
10    //创建私有属性
11 
12    public Employee(String name, double salary, int year, int month, int day)//定义变量
13    
14       this.name = name;
15       this.salary = salary;
16       hireDay = LocalDate.of(year, month, day);
17    
18 
19    public String getName()
20    
21       return name;
22    
23 
24    public double getSalary()
25    
26       return salary;
27    
28 
29    public LocalDate getHireDay()
30    
31       return hireDay;
32    
33    //访问器
34    
35    public void raiseSalary(double byPercent)
36    
37       double raise = salary * byPercent / 100;
38       salary += raise;
39    
40