foreach remove 時出現併發修改異常

例如：

List<Overlay> overlays = mapView.getOverlays();
// for (Overlay overlay : overlays) {
// if (overlay instanceof MyLocationOverlay
// | overlay instanceof MyPoiOverlay) {
// } else {
// overlays.remove(overlay);
// }
// }   直接remove併發異常

可改爲：

List<Overlay> overlays = mapView.getOverlays();
Overlay overlayToDel = null;
for (Overlay overlay : overlays) {
if (overlay instanceof MyLocationOverlay | overlay instanceof MyPoiOverlay) {

} else {
overlayToDel = overlay;
}
}
overlays.remove(overlayToDel);

或：

使用CopyOnWriteArrayList, CopyOnWriteArraySet實現,

List<String> list = new CopyOnWriteArrayList<String>();
list.add("Alpha");
list.add("Beta");
list.add("Cat");
list.add("Dog");
for (String s : list) {
    if (!"".equals(s)) {
        list.remove(s);
    }
}