Confused. Any comments welcomed.

```
public class PhoneDirectory {
PriorityQueue<Integer> pq = null;
int min = 0;
int max = 0;
/** Initialize your data structure here
@param maxNumbers - The maximum numbers that can be stored in the phone directory. */
public PhoneDirectory(int maxNumbers) {
pq = new PriorityQueue();
min = 0;
max = maxNumbers - 1;
}
/** Provide a number which is not assigned to anyone.
@return - Return an available number. Return -1 if none is available. */
public int get() {
if(min<=max) { int temp = min; min++; return temp; }
if( pq.size() > 0 ) {
int num = pq.poll();
pq.remove( num );
return num;
}
return -1;
}
/** Check if a number is available or not. */
public boolean check(int number) {
return (number>= min && number<= max ) || pq.contains( number );
}
/** Recycle or release a number. */
public void release(int number) {
if(min<=number && max>=number) return;
pq.offer( number );
}
}
/**
* Your PhoneDirectory object will be instantiated and called as such:
* PhoneDirectory obj = new PhoneDirectory(maxNumbers);
* int param_1 = obj.get();
* boolean param_2 = obj.check(number);
* obj.release(number);
*/
```