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package jdk.nashorn.internal;

Small helper class for fast int deques
/**
 * Small helper class for fast int deques
 */
public class IntDeque {
    private int[] deque = new int[16];
    private int nextFree = 0;

    
Push an int value
Params:
value – value/**
     * Push an int value
     * @param value value
     */
    public void push(final int value) {
        if (nextFree == deque.length) {
            final int[] newDeque = new int[nextFree * 2];
            System.arraycopy(deque, 0, newDeque, 0, nextFree);
            deque = newDeque;
        }
        deque[nextFree++] = value;
    }

    
Pop an int value
Returns:
value/**
     * Pop an int value
     * @return value
     */
    public int pop() {
        return deque[--nextFree];
    }

    
Peek
Returns:
top value/**
     * Peek
     * @return top value
     */
    public int peek() {
        return deque[nextFree - 1];
    }

    
Get the value of the top element and increment it.
Returns:
top value/**
     * Get the value of the top element and increment it.
     * @return top value
     */
    public int getAndIncrement() {
        return deque[nextFree - 1]++;
    }

    
Decrement the value of the top element and return it.
Returns:
decremented top value/**
     * Decrement the value of the top element and return it.
     * @return decremented top value
     */
    public int decrementAndGet() {
        return --deque[nextFree - 1];
    }

    
Check if deque is empty
Returns:
true if empty/**
     * Check if deque is empty
     * @return true if empty
     */
    public boolean isEmpty() {
        return nextFree == 0;
    }
}