集合第七发练习之利用ArrayList做栈、队列

 

栈：后进先出。

队列：先进先出。

利用这个核心思想，结合集合的add和remove方法做的栈和队列如下代码所示：

主类（t1（）和t2（）分别演栈和队列）：

 

1.  
   package cn.hncu.mySet2;
2.  
    
3.  
   import java.util.Iterator;
4.  
    
5.  
   import cn.hncu.set.Person;
6.  
    
7.  
   public class TestDemo {
8.  
   public static void main(String[] args) {
9.  
   t1();
10.  
    // t2();
11.  
     
12.  
     
13.  
    }
14.  
     
15.  
    private static void t1() {
16.  
    Person p1=new Person("01", "张三", 20);
17.  
    Person p2=new Person("02", "李四", 21);
18.  
    Person p3=new Person("03", "王五", 22);
19.  
    Person p4=new Person("04", "mis", 17);
20.  
     
21.  
    MyStack stack=new MyStack();
22.  
    stack.in(p1);
23.  
    stack.in(p2);
24.  
    stack.in(p3);
25.  
     
26.  
    System.out.println(stack.out());
27.  
    System.out.println(stack.out());
28.  
    System.out.println(stack.out());
29.  
    System.out.println(stack.out());
30.  
    System.out.println(stack.out());
31.  
    }
32.  
    private static void t2() {
33.  
    Person p1=new Person("01", "张三", 20);
34.  
    Person p2=new Person("02", "李四", 21);
35.  
    Person p3=new Person("03", "王五", 22);
36.  
    Person p4=new Person("04", "mis", 17);
37.  
    MyQueue queue=new MyQueue();
38.  
    queue.in(p1);
39.  
    queue.in(p2);
40.  
    queue.in(p3);
41.  
    queue.in(p4);
42.  
    System.out.println(queue.out());
43.  
    System.out.println(queue.out());
44.  
    System.out.println(queue.out());
45.  
    System.out.println(queue.out());
46.  
    System.out.println(queue.out());
47.  
     
48.  
    }
49.  
     
50.  
    }

栈类：

 

1.  
   package cn.hncu.mySet2;
2.  
    
3.  
   import java.util.ArrayList;
4.  
   import java.util.HashMap;
5.  
   import java.util.HashSet;
6.  
   import java.util.LinkedList;
7.  
   import java.util.List;
8.  
   import java.util.Set;
9.  
   import java.util.Stack;
10.  
     
11.  
    public class MyStack {
12.  
    private LinkedList mystack=new LinkedList();
13.  
    public void in(Object obj){
14.  
    mystack.add(obj);
15.  
    }
16.  
    public Object out(){
17.  
    if(mystack.isEmpty()){
18.  
    return null;
19.  
    }
20.  
    return mystack.removeLast();
21.  
    }
22.  
     
23.  
    public boolean isEmpty(){
24.  
    return mystack.isEmpty()?true:false;
25.  
    }
26.  
     
27.  
    }

队列类：

 

1.  
   package cn.hncu.mySet2;
2.  
    
3.  
   import java.util.LinkedList;
4.  
    
5.  
   public class MyQueue {
6.  
   private LinkedList list=new LinkedList();
7.  
   public void in(Object obj){
8.  
   list.add(obj);
9.  
   }
10.  
     
11.  
    public Object out(){
12.  
    if(list.isEmpty()){
13.  
    return null;
14.  
    }
15.  
    return list.remove(0);
16.  
    }
17.  
    public boolean isEmpty(){
18.  
    return list.isEmpty()?true:false;
19.  
    }
20.  
    }

person类：

 

1.  
   package cn.hncu.mySet2;
2.  
    
3.  
   public class Person {
4.  
   private String Sno;
5.  
   private String name;
6.  
   private int age;
7.  
   public Person(String sno, String name, int age) {
8.  
   super();
9.  
   Sno = sno;
10.  
    this.name = name;
11.  
    this.age = age;
12.  
    }
13.  
    public String getSno() {
14.  
    return Sno;
15.  
    }
16.  
    public void setSno(String sno) {
17.  
    Sno = sno;
18.  
    }
19.  
    public String getName() {
20.  
    return name;
21.  
    }
22.  
    public void setName(String name) {
23.  
    this.name = name;
24.  
    }
25.  
    public int getAge() {
26.  
    return age;
27.  
    }
28.  
    public void setAge(int age) {
29.  
    this.age = age;
30.  
    }
31.  
    @Override
32.  
    public String toString() {
33.  
    return "Person [Sno=" + Sno + ", name=" + name + ", age=" + age + "]";
34.  
    }
35.  
    @Override
36.  
    public int hashCode() {
37.  
    final int prime = 31;
38.  
    int result = 1;
39.  
    result = prime * result + ((Sno == null) ? 0 : Sno.hashCode());
40.  
    result = prime * result + age;
41.  
    result = prime * result + ((name == null) ? 0 : name.hashCode());
42.  
    return result;
43.  
    }
44.  
    @Override
45.  
    public boolean equals(Object obj) {
46.  
    if (this == obj)
47.  
    return true;
48.  
    if (obj == null)
49.  
    return false;
50.  
    if (getClass() != obj.getClass())
51.  
    return false;
52.  
    Person other = (Person) obj;
53.  
    if (Sno == null) {
54.  
    if (other.Sno != null)
55.  
    return false;
56.  
    } else if (!Sno.equals(other.Sno))
57.  
    return false;
58.  
    if (age != other.age)
59.  
    return false;
60.  
    if (name == null) {
61.  
    if (other.name != null)
62.  
    return false;
63.  
    } else if (!name.equals(other.name))
64.  
    return false;
65.  
    return true;
66.  
    }
67.  
     
68.  
    }