@Test(timeout = 5000)
public void isHeldByCurrentThread() {

    LockHandler lock = LockHandler.newReentrantLock();
    assertThat(lock.isHeldByCurrentThread()).isFalse();
    lock.run(() -> assertThat(lock.isHeldByCurrentThread()).isTrue());
    assertThat(lock.isHeldByCurrentThread()).isFalse();
}