Leetcode - 641 design cycle double ended queue (Design)*

class MyCircularDeque {
    
    // Underlying array structure 
    private int[] deque;
    // The head pointer 
    private int head;
    // Tail pointer 
    private int tail;
    // The number of actually stored numbers in the queue 
    private int size;
    // Queue capacity 
    private int capacity;
    public MyCircularDeque(int k) {
    
        deque = new int[k];
        head = 0;
        tail = 0;
        size = 0;
        capacity = k;
    }
    
    public boolean insertFront(int value) {
    
        // If the queue is full 
       if(isFull() == true)
          return false;
       else{
    
           // Insert at the position pointed by the head pointer value
           deque[head] = value;
           // The head pointer moves forward 
           head = (head -1 + this.capacity) % this.capacity;
           // Number of queue values plus one 
           size += 1;
           return true;
       }
    }
    
    public boolean insertLast(int value) {
    
        // If the queue is full 
       if(isFull() == true)
          return false;
       else{
    
            // The tail pointer moves backward 
           tail = (tail + 1 + this.capacity) % this.capacity;
           // Insert at the position pointed by the tail pointer value
           deque[tail] = value;
           // Number of queue values plus one 
           size += 1;
           return true;
       }
    }
    
    public boolean deleteFront() {
    
        // If the queue is empty 
        if(isEmpty())
          return false;
        else{
    
            head = (head + 1) % this.capacity;
            size -= 1;
            return true;
        }
    }
    
    public boolean deleteLast() {
    
        // If the queue is empty 
        if(isEmpty())
          return false;
        else{
    
            tail = (tail -1  + this.capacity) % this.capacity;
            size -= 1;
            return true;
        }
    }
    
    public int getFront() {
    
         if(isEmpty())
            return -1;
        else{
    
            int front = (head + 1) % this.capacity;
            return deque[front];
        }
    }
    
    public int getRear() {
    
        if(isEmpty())
            return -1;
        else{
    
            return deque[tail];
        }
    }
    
    public boolean isEmpty() {
    
       return this.size == 0;
    }
    
    public boolean isFull() {
    
        return this.capacity == this.size;
    }
}

/** * Your MyCircularDeque object will be instantiated and called as such: * MyCircularDeque obj = new MyCircularDeque(k); * boolean param_1 = obj.insertFront(value); * boolean param_2 = obj.insertLast(value); * boolean param_3 = obj.deleteFront(); * boolean param_4 = obj.deleteLast(); * int param_5 = obj.getFront(); * int param_6 = obj.getRear(); * boolean param_7 = obj.isEmpty(); * boolean param_8 = obj.isFull(); */