BoundedQueue.java

package synthesizer;

import java.util.Iterator;

public interface BoundedQueue<T> extends Iterable<T> {
    int capacity();     // return size of the buffer

    int fillCount();    // return number of items currently in the buffer

    void enqueue(T x);  // add item x to the end

    T dequeue();        // delete and return item from the front

    T peek();           // return (but do not delete) item from the front

    default boolean isEmpty() {      // is the buffer empty (fillCount equals zero)?
        return fillCount() == 0;
    }

    default boolean isFull() {       // is the buffer full (fillCount is same as capacity)?
        return fillCount() == capacity();
    }

    public Iterator<T> iterator();
}