数组实现Java 自定义Queue队列及应用操作

package com.queue;
import java.util.Arrays;

public class Queue {
    // Define capacity constant: CAPACITY
    private static final int CAPACITY = 1024;
    // Define capacity of queue
    private static int capacity;
    // Front of queue
    private static int front;
    // Tail of queue
    private static int tail;
    // Array for queue
    private static Object[] array;

    // Constructor of Queue class
    public Queue() {
        this.capacity = CAPACITY;
        array = new Object[capacity];
        front = tail = 0;
    }

    // Get size of queue
    public static int getSize() {
        if (isEmpty())
            return 0;
        else
            return (capacity + tail - front) % capacity;
    }

    // Whether is empty
    public static boolean isEmpty() {
        return (front == tail);
    }

    // put element into the end of queue
    public static void enqueue(Object element) throws ExceptionQueueFull {
        if (getSize() == capacity - 1)
            throw new ExceptionQueueFull("Queue is full");
        array[tail] = element;
        tail = (tail + 1) % capacity;
    }

    // get element from queue
    public static Object dequeue() throws ExceptionQueueEmpty {
        Object element;
        if (isEmpty())
            throw new ExceptionQueueEmpty("Queue is empty");
        element = array[front];
        front = (front + 1) % capacity;
        return element;
    }

    // Get the first element for queue
    public static Object frontElement() throws ExceptionQueueEmpty {
        if (isEmpty())
            throw new ExceptionQueueEmpty("Queue is empty");
        return array[front];
    }

    // Travel all elements of queue
    public static void getAllElements() {
        Object[] arrayList = new Object[getSize()];

        for (int i = front,j = 0; j < getSize(); i ++,j ++) {
                arrayList[j] = array[i];
        }
        System.out.println("All elements of queue: "
                + Arrays.toString(arrayList));
    }
}

package com.queue;
public class ExceptionQueueEmpty extends Exception {
    // Constructor
    public ExceptionQueueEmpty() {

    }
    // Constructor with parameters
    public ExceptionQueueEmpty(String mag) {
        System.out.println(mag);
    }
}

package com.queue;
public class ExceptionQueueFull extends Exception {
    // Constructor
    public ExceptionQueueFull() {
    }

    // Constructor with parameters
    public ExceptionQueueFull(String mag) {
        System.out.println(mag);
    }
}

package com.queue;

public class QueueTest {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        Queue queue = new Queue();
        System.out.println("The size of queue is: " + queue.getSize());
        System.out.println("Is empty: " + queue.isEmpty());
        try {
            queue.enqueue(8);
            queue.enqueue(3);
            queue.enqueue(5);
            queue.enqueue(7);
            queue.enqueue(9);
            queue.getAllElements();
            System.out.println("The size of queue is: " + queue.getSize());
            System.out.println("Is empty: " + queue.isEmpty());
            System.out.println("The front element of queue: "
                    + queue.frontElement());
            System.out.println(queue.dequeue());
            System.out.println(queue.dequeue());
            System.out.println(queue.dequeue());
            System.out.println(queue.dequeue());
            System.out.println(queue.dequeue());
            System.out.println("The size of queue is: " + queue.getSize());
            System.out.println("Is empty: " + queue.isEmpty());
        } catch (ExceptionQueueFull e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (ExceptionQueueEmpty e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
}

package com.queue;
public class QueueBuilder {
    // Building string type array for queue
    public static Queue queueBuild(String[] str) {
        Queue queue = new Queue();

        for (int i = 0; i < str.length; i++) {
            try {
                queue.enqueue(str[i]);
            } catch (ExceptionQueueFull e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        return queue;
    }

    // Weed out the kth kid who get the sweet potato
    public static String gameWiner(Queue queue, int k)
            throws ExceptionQueueFull, ExceptionQueueEmpty {

        if (queue.isEmpty())
            return null;
        while (queue.getSize() > 1) {
            queue.getAllElements();// Output recently queue
            for (int i = 0; i < k - 1; i++)
                queue.enqueue(queue.dequeue());
            System.out.println("\n\t" + queue.dequeue() + ": Weep out");
        }
        return (String) queue.dequeue();
    }
}

package com.queue;
public class QueueGame {

    public static void main(String[] args) throws ExceptionQueueFull, ExceptionQueueEmpty {
        // TODO Auto-generated method stub
        String[] kid = {"Alice", "Bob", "Cindy", "Doug", "Ed",
                        "Fred", "Gene", "Hope", "Irene", "Jack",
                        "Kim", "Lance", "Mike", "Nancy", "Ollie"};
        QueueBuilder qb = new QueueBuilder();
        System.out.println("The luck dog is: " + qb.gameWiner(qb.queueBuild(kid), 5));
    }
}

package com.tangbaobao.queue;
import com.tangbaobao.LinkedList.MyLinkedList;

public class MyQueue {
    private int size;
    MyLinkedList linkedList = null;
    
    public void enqueue(int value) {
        if (linkedList == null) {
            linkedList = new MyLinkedList();
        }
        linkedList.add(value);
        size++;
    }
    
    public Object dequeue() {
        Object value = 0;
        if (linkedList != null) {
            //每次弹出队列的头
            value = linkedList.get(0);
            linkedList.removeAt(0);
            size--;
        } else {
            try {
                throw new Exception("队列中没有元素");
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return value;
    }
    
    public int size() {
        return size;
    }
}

package com.tangbaobao.queue;
import java.util.ArrayList;
import java.util.List;

public class ListQueue {
    private int size;
    private List<Object> list = null;
    public void enqueue(int value) {
        if (list == null) {
            list = new ArrayList<>();
        }
        list.add(value);
        size++;
    }
    public Object dequeue() {
        Object value = 0;
        if (list != null) {
            value = list.get(0);
            list.remove(0);
            size--;
        } else {
            try {
                throw new Exception("队列中没有元素");
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        return value;
    }
    
    public int size() {
        return size;
    }
}