需要帮助调试JSF转换错误

Question

我是一名JSF新手并接管了一个现有项目。我通过模仿在另一个选项卡上完成的操作在UI中创建了一个新选项卡。除了有一个按钮（h：commandLink）删除显示列表中的一行数据外，所有工作都或多或少都有效。当我单击按钮时出现转换错误。分配给commandLink的动作功能甚至不被调用。我尝试过添加，但所有内容都是＆＃34;转换错误＆＃34;，这对我来说或多或少是无用的。有人可以帮我找出调试转换错误的方法吗？

以下是我的jsp文件的片段：

<h:commandLink rendered="#{!surveyContactListListHandler.disableDelete && surveyContactListHandler.updateRendered}" styleClass="imageButtonLink deleteButton"
    value="" action="#{surveyContactListListHandler.delete}">
    <h:graphicImage styleClass="buttonImg" value="/images/_delete.gif" title="#{labels.deleteButtonLabel}">
    </h:graphicImage>
</h:commandLink>

我的SurveyContactListListHandler派生自AbstractListHandler。这是相关功能，但正如我所说，它甚至从未被调用过，所以我不确定为什么它的相关性：

public abstract class AbstractListHandler extends AbstractHandler implements ListHandler
{
   public String delete() {
     try {
        List idsToDelete = getCurrentIds();
        // If there's just one id to delete, use the simpler version of the method
        int numItemsToDelete = idsToDelete.size();
        if ((numItemsToDelete == 1) && (((Integer) idsToDelete.get(0))).intValue() == getCurrentId()) {
            return deleteOneRow(getCurrentId(), getCurrentDisplayIndex());
        }

        // delete all the ids
        for (int i = 0; i < numItemsToDelete; i++) {
            Integer idToDelete = (Integer) idsToDelete.get(i);
            deleteItem(idToDelete.intValue());
        }

        // the wrapped data still has all the items including the
        // deleted ones. Figure out which one to select next.

        List dataList = (List) listDataModel.getWrappedData();
        if (numItemsToDelete == dataList.size()) {
            // all items were removed. no item is selected.
            setCurrentId(-1);
        } else {
            // the logic is: if there are items after the last item
            // to delete, select the one right after the last deleted index.
            // if the last deleted item is also the last item in the list, find the
            // last non-deleted item and select it.

            // first we want to figure out tha last deleted index,
            // last non-deleted index and the number of deleted items
            // there are after the last non deleted index

            int maxDeletedIndex = -1;
            int maxNonDeletedIndex = -1;
            int numDeletedItemsFound = 0;

            for (int i = (getRealSize(dataList) - 1); i >= 0 ; i--) {
                Object item = dataList.get(i);
                int itemId = getItemId(item);
                int itemIndex = getItemIndex(item);
                if (idsToDelete.contains(new Integer(itemId))) {
                    // this item is one of the deleted items
                    numDeletedItemsFound ++;
                    if (maxDeletedIndex == -1) {
                        maxDeletedIndex = itemIndex;

                        if (maxNonDeletedIndex != -1) {
                            // We already found non deleted items
                            // which means this is the last deleted item
                            // and there are non-deleted items after this one
                            // we want to select the first item after the last
                            // deleted item
                            setCurrentId(getItemId(dataList.get(maxDeletedIndex + 1)));
                            break;
                        }
                    }
                } else {
                    // this item is not one of the deleted items
                    if (maxNonDeletedIndex == -1) {
                        maxNonDeletedIndex = itemIndex;

                        if (maxDeletedIndex != -1) {
                            // We already found deleted items
                            // which means this is the last non-deleted item
                            // and there are only deleted items after this one
                            // we want to select the last non-deleted item
                            setCurrentId(itemId);
                        }
                    }
                }
            }
        }

        setReload(true);
        return "deleted";
      } catch (Exception e) {
        e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        addMessage(null, e.getMessage());
        return "error";
      }
    }
}