RemoteViewsService.RemoteViewsFactory中的ArrayIndexOutOfBoundsException

Question

我遇到以下异常：

  

java.lang.ArrayIndexOutOfBoundsException：length = 6;索引= 6
  03-26 10：52：09.729：E / AndroidRuntime（19956）：at java.util.Collections.sort（Collections.java:1909）
  03-26 10：52：09.729：E / AndroidRuntime（19956）：位于com.mycompany.widget.AlertItemRemoteViewsService $ a.onDataSetChanged（SourceFile：53）
  03-26 10：52：09.729：E / AndroidRuntime（19956）：位于android.widget.RemoteViewsService $ RemoteViewsFactoryAdapter.onDataSetChanged（RemoteViewsService.java:142）
  03-26 10：52：09.729：E / AndroidRuntime（19956）：在com.android.internal.widget.IRemoteViewsFactory $ Stub.onTransact（IRemoteViewsFactory.java:49）
  03-26 10：52：09.729：E / AndroidRuntime（19956）：at

这不容易重现。

发生这种情况的代码如下：

public class AlertItemRemoteViewsService extends RemoteViewsService {
    @Override
    public RemoteViewsFactory onGetViewFactory(Intent intent) {
        return new AlertItemRemoteViewsFactory(this.getApplicationContext(), intent);
    }

    class AlertItemRemoteViewsFactory implements RemoteViewsFactory {

        private List<AlertItem> mItems;

        private Context mContext;
        private final Intent mIntent;

        public AlertItemRemoteViewsFactory(final Context context, final Intent intent) {
            mContext = context;
            mItems = new LinkedList<>();
            mIntent = intent;
        }

        @Override
        public void onCreate() {
        }

        @Override
        public void onDataSetChanged() {
            mItems.clear();
            if (new EulaRequirement().isAccepted(mContext)) {
                List<AlertItem> items = AlertManager.getInstance().getAllAlerts(mContext);
                for (AlertItem item : items) {
                    if (!item.getShouldBeIgnored()) {
                        mItems.add(item);
                    }
                }
                Collections.sort(mItems, new AlertsListAdapter.ItemComparatorByAlertCategory(mContext));
            }
        }

        @Override
        public void onDestroy() {
            mItems = null;
            mContext = null;
        }

        @Override
        public int getCount() {
            return mItems.size();
        }

        ...
}

它发生在“ Collections.sort”行上。从RemoteViewsFactory的文档开始： “注意：昂贵的任务可以在此方法中安全地同步执行。在此期间，旧数据将显示在小部件内。”

因此，该调用似乎不需要任何同步，那么，这种异常怎么会发生，有什么想法？

更新：这是比较器：

public static class ItemComparatorByAlertCategory implements Comparator<AlertItem>, Serializable {

        private static final long serialVersionUID = 1L;

        private final Context mContext;

        public ItemComparatorByAlertCategory(final Context context) {
            mContext = context;
        }

        @Override
        public int compare(final AlertItem alertItem1, final AlertItem alertItem2) {
            int result = alertItem1.getEAlertItem().getAlertCategory().compareTo(alertItem2.getEAlertItem().getAlertCategory());
            // If they are not from the same category we return the result, otherwise we compare also the icons (the source of the alert, like Scanner, L&T and so on.)
            if (result != 0) {
                return result;
            } else {
                return Integer.compare(
                        alertItem1.getEAlertItem().getHandlerFactory().newInstance(mContext).getDrawableId(),
                        alertItem2.getEAlertItem().getHandlerFactory().newInstance(mContext).getDrawableId());
            }
        }
    }