本文共 2171 字，大约阅读时间需要 7 分钟。

package DataDtructure;/** * ClassName: LoopQueue * Company:华中科技大学电气学院 * date: 2019/8/23 16:23 * author： YEXIN * version： 1.0 * since： JDK 1.8 * Description:实现循环队列，不再使用动态数组了 */public class LoopQueue
   
     implements Queue
    
      {    private E[] data;    private int front,tail;    private int size;    public LoopQueue(int capacity){        data = (E[])new Object[capacity+1];        front = 0;        tail = 0;        size = 0;    }    public LoopQueue(){        this(10);    }    public int getCapacity(){        return data.length -1;    }    @Override    public int getSize() {        return size;    }    @Override    public boolean isEmpty() {        return tail == front;    }    @Override    public void enqueue(E e) {        if((tail+1)% data.length == front){//队列满了            resize(getCapacity()*2);//扩容        }        data[tail] = e;        tail  = (tail+1)%data.length;        size++;    }    private void resize(int newCapacity){        E[] newdata = (E[])new Object[newCapacity + 1];        for(int i = 0;i < size; i++){            newdata[i] = data[(i+front)% data.length];        }        data = newdata;        front = 0;        tail = size;    }    @Override    public E getFront() {        if(isEmpty()){            throw new IllegalArgumentException("the Queue is empty");        }        return data[front];    }    @Override    public E dequeue() {        if(isEmpty()){            throw new IllegalArgumentException("the Queue is empty");        }        E res =  data[front];        data[front]=null;        front = (front+1)%data.length;        size--;        if(size == getCapacity()/4 && data.length/2 != 0){            resize(data.length/2);        }        return res;    }    @Override    public String toString(){        StringBuilder res = new StringBuilder();        res.append(String.format("Queue:size = %d,capacity = %d\n",size,getCapacity()));        res.append("front [");        for(int i = front ;i != tail; i=(i+1)%data.length){            res.append(data[i]);            if((i+1)%data.length != tail){                 res.append(",");            }        }        res.append("] tail");        return res.toString();    }}
    
   

转载地址：http://achjn.baihongyu.com/