基于順序表的隊列：

package StackExercise;

public class OrderQueue<T> {
   //默認的最大長度
   public static final int DEFAULT_SIZE = 20;
   //最大長度
   private int maxSize;
   //當前隊列
   private Object[] objs;
   //隊列頭
   private int head;
   //隊列尾
   private int tail;
   //隊列長度
   private int size;

   //初始化
   public OrderQueue() {
       this(DEFAULT_SIZE);
   }

   //初始化
   public OrderQueue(int size) {
       head = 0;
       tail = 0;
       maxSize = size;
       objs = new Object[maxSize];
   }

   //獲取隊列長度
   public int getLength() {
       return size;
   }

   //出隊
   public T deQueue() {
       T ret = null;
       if (size <= 0) {
           throw new RuntimeException("隊列為空!");
       } else {
           size--;
           ret = (T) objs[head];
           objs[head] = null;
           head = ++head % maxSize;
       }
       return ret;

   }

   //入隊
   public void enQueue(T t) {
       if (size == maxSize) {
           throw new RuntimeException("隊列已滿!");
       } else {
           size++;
           objs[tail] = (Object) t;
           tail = ++tail % maxSize;
       }
   }

   //打印
   public void print() {
       int start = head;
       while (start != tail) {
           System.out.print(objs[start] + "\n");
           start = ++start % maxSize;
       }
   }
}

基于鏈表形式的有空再補充。