Here is my implementation of CyclicBarrier

public class CyclicBarrier {
    int numParties, arrived;
    Semaphore mutex;
    Semaphore barrier1, barrier2;

    public CyclicBarrier(int parties) {
        // TODO: The constructor for this CyclicBarrier
        this.numParties = parties; //Total number of threads
        this.arrived = 0;   //Initially zero
        mutex = new Semaphore(1);
        barrier1 = new Semaphore(0); //Initially Closed
        barrier2 = new Semaphore(1); //Initially Open
    }

    public void await() throws InterruptedException {
        phase1(); //Phase 1 ensures that all threads wait at the barrier
        phase2(); //Phase 2 resets the Cyclic barrier for reuse
    }

    void phase1() throws InterruptedException {
        mutex.acquire();
        arrived++;

        if(arrived == numParties){
            barrier2.acquire(); // Close barrier 2
            barrier1.release(); // Release one thread  from barrier 1
        }
        mutex.release();

        barrier1.acquire();
        barrier1.release();
    }

    void phase2() throws InterruptedException {
        mutex.acquire();
        arrived--;

        if(arrived == 0){
            barrier1.acquire(); // Close barrier 1
            barrier2.release(); // Let one thread go through barrier 2
        }
        mutex.release();

        barrier2.acquire();
        barrier2.release(); // Each thread passes through will signal one other thread
    }

}

Two questions

1. Is this correct?
2. If I only call phase1 from the class that consumes this barrier, does it become a countdown latch?