Queue的java实现

 1 package com.liu.queue;
 2 
 3 public class QueueApp {
 4     public static void main(String args[])
 5     {
 6         Queue theQueue = new Queue(5);
 7         
 8         theQueue.insert(10);
 9         theQueue.insert(20);
10         theQueue.insert(30);
11         //theQueue.insert(40);
12         
13         theQueue.remove();
14         theQueue.remove();
15         theQueue.remove();
16         
17         theQueue.insert(50);
18         theQueue.insert(60);
19         theQueue.insert(70);
20         theQueue.insert(80);
21         
22         while(!theQueue.isEmpty())
23         {
24             long n = theQueue.remove();
25             System.out.print(n);
26             System.out.print(" ");
27         }
28         System.out.println("");
29     }
30 }
31 
32 class Queue
33 {
34     private int maxsize;
35     private long[] queArray;
36     private int front;
37     private int rear;
38     private int nItems;
39     
40     public Queue(int s)
41     {
42         maxsize = s;
43         queArray = new long[maxsize];
44         front = 0;
45         rear = -1;
46         nItems = 0;
47     }
48     
49     public void insert(long j)
50     {
51         if(rear == maxsize-1)
52             rear = -1;//如果尾指针已经到了最后，则循环
53         queArray[++rear] = j;
54         nItems++;
55     }
56     
57     public long remove()
58     {
59         long temp = queArray[front++];
60         if(front == maxsize)
61             front = 0;
62         nItems--;
63         return temp;
64     }
65     
66     public long peekFront()
67     {
68         return queArray[front];
69     }
70     
71     public boolean isEmpty()
72     {
73         return (nItems == 0);
74     }
75     
76     public boolean isFull()
77     {
78         return (nItems == maxsize);
79     }
80     
81     public int size()
82     {
83         return nItems;
84     }
85     
86     
87 }