Queue data structure : Queue « Collections Data Structure « Java

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Java » Collections Data Structure » QueueScreenshots 
Queue data structure
Queue data structure
     
public class Queue {
  private int maxSize;

  private long[] queArray;

  private int front;

  private int rear;

  private int nItems;

  public Queue(int s) {
    maxSize = s;
    queArray = new long[maxSize];
    front = 0;
    rear = -1;
    nItems = 0;
  }

  //   put item at end of a queue
  public void insert(long j) {
    if (rear == maxSize - 1// deal with wraparound
      rear = -1;
    queArray[++rear= j; // increment rear and insert
    nItems++; 
  }

  //   take item from front of queue
  public long remove() {
    long temp = queArray[front++]// get value and incr front
    if (front == maxSize// deal with wraparound
      front = 0;
    nItems--; // one less item
    return temp;
  }

  public long peekFront() {
    return queArray[front];
  }

  public boolean isEmpty() {
    return (nItems == 0);
  }

  public boolean isFull() {
    return (nItems == maxSize);
  }

  public int size() {
    return nItems;
  }

  public static void main(String[] args) {
    Queue theQueue = new Queue(5)// queue holds 5 items

    theQueue.insert(10);
    theQueue.insert(20);
    theQueue.insert(30);
    theQueue.insert(40);

    theQueue.remove()
    theQueue.remove()
    theQueue.remove();

    theQueue.insert(50)
    theQueue.insert(60)//    (wraps around)
    theQueue.insert(70);
    theQueue.insert(80);

    while (!theQueue.isEmpty()) {
      long n = theQueue.remove()// (40, 50, 60, 70, 80)
      System.out.print(n);
      System.out.print(" ");
    }
    System.out.println("");
  }
}
           
         
    
    
    
    
  
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4.Simple Queue (FIFO) based on LinkedList
5.The Generic Queue Class
6.Blocking Queue
7.Circular Queue
8.Circular Queue extends AbstractList
9.How to extend the collections framework
10.An unbounded {@link TransferQueue} based on linked nodes.
11.This class implements the data structures necessary for an ArrayQueue
12.A circular queue from mina
13.An unbounded TransferQueue based on linked nodes.
14.Rotating queue of fixed size.
15.Allows threads to communicate asynchronously by putting messages into and reading messages out of a synchronized queue.
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