/** Adds the alarm item. Must be called from within the heap lock. */
private boolean insertImpl(Alarm alarm) {
if (alarm.getHeapIndex() != 0) throw new IllegalStateException();
// resize if necessary
if (_heap.length <= _heapTop + 2) {
Alarm[] newHeap = new Alarm[2 * _heap.length];
System.arraycopy(_heap, 0, newHeap, 0, _heap.length);
_heap = newHeap;
}
Alarm[] heap = _heap;
int i = ++_heapTop;
int parent = 0;
Alarm item = null;
long wakeTime = alarm.getWakeTime();
while (i > 1 && wakeTime < (item = heap[parent = (i >> 1)]).getWakeTime()) {
heap[i] = item;
item.setHeapIndex(i);
i = parent;
}
heap[i] = alarm;
alarm.setHeapIndex(i);
if (_heapTop < i) throw new IllegalStateException("i=" + i + " top=" + _heapTop);
if (i < 1) throw new IllegalStateException("i=" + i);
return (i == 1);
}
void testClear() {
for (; _heapTop > 0; _heapTop--) {
Alarm alarm = _heap[_heapTop];
alarm.setHeapIndex(0);
_heap[_heapTop] = null;
}
}
/** Removes the alarm item. Must be called from within the heap lock. */
private void dequeueImpl(Alarm item) {
int i = item.getHeapIndex();
if (i < 1) return;
if (_heapTop < i) throw new IllegalStateException("bad heap: " + _heapTop + " index:" + i);
Alarm[] heap = _heap;
if (_heapTop < 1) throw new IllegalStateException();
int size = _heapTop--;
heap[i] = heap[size];
heap[i].setHeapIndex(i);
heap[size] = null;
item.setHeapIndex(0);
if (size == i) return;
if (item.getWakeTime() < heap[i].getWakeTime()) {
while (i < size) {
item = heap[i];
int minIndex = i;
long minWakeTime = item.getWakeTime();
int left = i << 1;
if (left < size && heap[left].getWakeTime() < minWakeTime) {
minIndex = left;
minWakeTime = heap[left].getWakeTime();
}
int right = left + 1;
if (right < size && heap[right].getWakeTime() < minWakeTime) minIndex = right;
if (i == minIndex) return;
heap[i] = heap[minIndex];
heap[i].setHeapIndex(i);
heap[minIndex] = item;
item.setHeapIndex(minIndex);
i = minIndex;
}
} else {
int parent;
Alarm alarm;
item = heap[i];
long wakeTime = item.getWakeTime();
while (i > 1 && wakeTime < (alarm = heap[parent = (i >> 1)]).getWakeTime()) {
heap[i] = alarm;
alarm.setHeapIndex(i);
i = parent;
}
heap[i] = item;
item.setHeapIndex(i);
}
}
