JS Bin// source https://jsbin.com/dafobir

circularQueue.js

 
 class circularQueue{
   
  constructor(max){
    
    this.array = [];
    this.max= max; 
    this.length = 0;
    this.front = 0;
    this.end = 0;
    
    
    for(let i = 0; i < this.max; i++){
      
      this.array[i] = null;
      
    } 
    
  } 
   
  get isFull(){
     
     return this.length === this.max;
     
   }
   
   
   get isEmpty(){
     
     return this.length === 0;
     
   }
   
   
   get peek(){
     return this.array[this.front];
   }
   
  
  add(item) {
    
    if(!this.isFull){
      this.array[this.end] = item;
      this.length++;
      this.end = (this.end + 1)% this.max;
      
     
    }else{
      console.error('Queue is full.');
    }
        
    
    this.log();
    

  }
   
  
  
  remove(){
    
    if(!this.isEmpty){
      this.array[this.front] = null;
      this.length--;
      this.front = (this.front + 1)% this.max;
    }else{
      
      console.error('Queue is empty.');
      
    }
    
    
    this.log();
  }
   
   
  log(){
    console.log('length is: ' + this.length);
    console.log('front is: ' + this.front);
    console.log('end is: ' + this.end);
    console.log('Peek: ' + this.peek);
    console.log(this.array);
  }
  
}


// Create a circular queue of length 3
let numbers = new circularQueue(3);