[英]Seemingly random NullPointerException when updating a TreeTableView
我只是将过滤添加到TreeTableView中，并且开始出现似乎是随机的错误（可能不是随机的）。 我可以通过向过滤器textField发送垃圾邮件来重现它，以更新TreeTableView直到出现阻塞。 我得到以下堆栈跟踪，TreeTableView不再更新，但程序不会崩溃。 与我的代码相关的堆栈跟踪的唯一部分指向cellFactory，在其中我重写CheckBoxTreeTableCell的updateItem以便为顶层行实现样式：
colActShop.setCellFactory(column ->{
return new CheckBoxTreeTableCell<Product, Boolean>(){
@Override
public void updateItem(Boolean item, boolean empty) {
super.updateItem(item, empty);
boolean isTopLevel = getTreeTableView().getRoot().getChildren()
.contains(getTreeTableRow().getTreeItem());
if(item == null || empty){
setText(null);
setGraphic(null);
//It crashes on the following line according to the stack trace
getTreeTableRow().getStyleClass().remove("topLevelRow");
}else{
if(isTopLevel){
getTreeTableRow().getStyleClass().add("topLevelRow");
}else{
getTreeTableRow().getStyleClass().remove("topLevelRow");
}
setEditable(!isTopLevel);
}
}
};
});
如果我删除了getTreeTableRow().getStyleClass()...行，则似乎正在删除该错误，但随后我失去了正在寻找的样式行为。 我也拼命尝试在某些地方放置一些Platform.runlater ，但没有成功。 由于过滤和TreeTableView更新变得越来越大，我现在无法提供一个最小的可执行示例。 当我在过滤器textField中输入文本时，将调用以下函数来更新TreeTableView的根：
/**
* A method to update a TreeTableView every time backing data changes in the model,
* without resetting the table by only adding and removing data when required.
* Also applies filters
* @param root : the root TreeItem of the table to update
* @param inventory : the inventory backing this table
* @param shop : the shop to calculate the price of products
* @param filter : comma separated string filter
* @param catFilter : category filter list
*/
private void updateTreeItemRoot(TreeItem<Product> root, Inventory inventory, Shop shop, String filter, ArrayList<String> catFilter){
inventory.clean();
shop.clean();
inventory.calculateAverageData();
//retrieve the product list of category items of the previous TreeTableView structure before updating
ArrayList<Product> oldProdCategoryList= new ArrayList<Product>();
ArrayList<TreeItem<Product>> oldTreeItemCategoryList= new ArrayList<>(root.getChildren());
for(TreeItem<Product> treeItem : oldTreeItemCategoryList){
oldProdCategoryList.add(treeItem.getValue());
}
for(Entry<String, ArrayList<Product>> entry : inventory.getData().entrySet()){
Product product = inventory.getAverageData(entry.getKey());
//Filtering the TreeTableView
boolean filterOK = false;
if(catFilter!=null){
if(catFilter.contains("All")||catFilter.contains("All seeds")){
filterOK = true;
}else{
//else look for any matching categories
for(String str:catFilter){
if(product.getCategories().stream().anyMatch(s -> s.equals(str))){
filterOK = true;
break;
}
}
}
//turn filterOk to false if we want only mature and product is not
if(catFilter.contains("Only mature")&&product.getMaturity()!=100) {
filterOK = false;
}
//turn filterOK to false if we want only seeds and the product is not a seed
if(catFilter.contains("Only seeds")){
if(!(product.getCategories().stream().anyMatch(s -> s.equals("Seed")))){
filterOK = false;
}
}
}else{
filterOK = true;
}
String[] filterList = filter.split(",");
if(filter.length()>0&&!Arrays.stream(filterList).anyMatch(s->product.getName().matches( "(?i:.*"+s+".*)"))){
filterOK = false;
}
if(filterOK){
product.updatePrice(shop);
TreeItem<Product> averageProdDataItem; ;
//if this product category is not yet present in the table add it.
if(!oldProdCategoryList.contains(product)){
averageProdDataItem = new TreeItem<Product>(product);
averageProdDataItem.setExpanded(true);
root.getChildren().add(averageProdDataItem);
}else{
//else if this product category is already in the table, retrieve the reference and remove it from the
// "old" Lists to see if something needs to be removed from the table in the end
averageProdDataItem = oldTreeItemCategoryList.get(oldProdCategoryList.indexOf(product));
oldTreeItemCategoryList.remove(oldProdCategoryList.indexOf(product));
oldProdCategoryList.remove(product);
}
//retrieve the product list for this category category of the previous TreeTableView structure before updating
ArrayList<Product> oldProdList= new ArrayList<Product>();
ArrayList<TreeItem<Product>> oldTreeItemList= new ArrayList<>(averageProdDataItem.getChildren());
for(TreeItem<Product> treeItem : oldTreeItemList){
oldProdList.add(treeItem.getValue());
}
for(Product prod : entry.getValue()){
prod.updatePrice(shop);
TreeItem<Product> treeItem;
//if the table does not contain this prod, add it
if(!oldProdList.contains(prod)){
treeItem = new TreeItem<Product>(prod);
averageProdDataItem.getChildren().add(treeItem);
}else{
oldTreeItemList.remove(oldProdList.indexOf(prod));
oldProdList.remove(prod);
}
}
averageProdDataItem.getChildren().removeAll(oldTreeItemList); //clean up empty products
}// if filterOK
}//for
root.getChildren().removeAll(oldTreeItemCategoryList);// clean up empty categories
}
这似乎是相同的这个问题已经打开的3倍和关闭没有任何评论。
堆栈跟踪：
Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
at com.sun.javafx.scene.control.skin.CellSkinBase.access$200(CellSkinBase.java:54)
at com.sun.javafx.scene.control.skin.CellSkinBase$StyleableProperties$1.getStyleableProperty(CellSkinBase.java:149)
at com.sun.javafx.scene.control.skin.CellSkinBase$StyleableProperties$1.getStyleableProperty(CellSkinBase.java:138)
at javafx.scene.CssStyleHelper.resetToInitialValues(CssStyleHelper.java:447)
at javafx.scene.CssStyleHelper.createStyleHelper(CssStyleHelper.java:180)
at javafx.scene.Node.reapplyCss(Node.java:8983)
at javafx.scene.Node.reapplyCss(Node.java:9012)
at javafx.scene.Node.impl_reapplyCSS(Node.java:8946)
at javafx.scene.Node$3.onChanged(Node.java:1023)
at com.sun.javafx.collections.TrackableObservableList.lambda$new$29(TrackableObservableList.java:45)
at com.sun.javafx.collections.ListListenerHelper$SingleChange.fireValueChangedEvent(ListListenerHelper.java:164)
at com.sun.javafx.collections.ListListenerHelper.fireValueChangedEvent(ListListenerHelper.java:73)
at javafx.collections.ObservableListBase.fireChange(ObservableListBase.java:233)
at javafx.collections.ListChangeBuilder.commit(ListChangeBuilder.java:482)
at javafx.collections.ListChangeBuilder.endChange(ListChangeBuilder.java:541)
at javafx.collections.ObservableListBase.endChange(ObservableListBase.java:205)
at javafx.collections.ModifiableObservableListBase.remove(ModifiableObservableListBase.java:183)
at javafx.collections.ModifiableObservableListBase.remove(ModifiableObservableListBase.java:171)
at homier.farmGame.controller.Engine$2.updateItem(Engine.java:768)
at homier.farmGame.controller.Engine$2.updateItem(Engine.java:1)
at javafx.scene.control.TreeTableCell.updateItem(TreeTableCell.java:630)
at javafx.scene.control.TreeTableCell.indexChanged(TreeTableCell.java:457)
at javafx.scene.control.IndexedCell.updateIndex(IndexedCell.java:116)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.recreateCells(TableRowSkinBase.java:671)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.updateCells(TableRowSkinBase.java:499)
at com.sun.javafx.scene.control.skin.TreeTableRowSkin.updateCells(TreeTableRowSkin.java:220)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.checkState(TableRowSkinBase.java:631)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.computePrefHeight(TableRowSkinBase.java:571)
at javafx.scene.control.Control.computePrefHeight(Control.java:547)
at javafx.scene.Parent.prefHeight(Parent.java:935)
at javafx.scene.layout.Region.prefHeight(Region.java:1435)
at com.sun.javafx.scene.control.skin.VirtualFlow.resizeCellSize(VirtualFlow.java:1947)
at com.sun.javafx.scene.control.skin.VirtualFlow.addLeadingCells(VirtualFlow.java:1247)
at com.sun.javafx.scene.control.skin.VirtualFlow.layoutChildren(VirtualFlow.java:1194)
at javafx.scene.Parent.layout(Parent.java:1087)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Scene.doLayoutPass(Scene.java:552)
at javafx.scene.Scene$ScenePulseListener.pulse(Scene.java:2397)
at com.sun.javafx.tk.Toolkit.lambda$runPulse$29(Toolkit.java:398)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.Toolkit.runPulse(Toolkit.java:397)
at com.sun.javafx.tk.Toolkit.firePulse(Toolkit.java:424)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:518)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:498)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulseFromQueue(QuantumToolkit.java:491)
at com.sun.javafx.tk.quantum.QuantumToolkit.lambda$runToolkit$403(QuantumToolkit.java:319)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
at java.lang.Thread.run(Unknown Source)
Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
at com.sun.javafx.scene.control.skin.CellSkinBase.access$200(CellSkinBase.java:54)
at com.sun.javafx.scene.control.skin.CellSkinBase$StyleableProperties$1.getStyleableProperty(CellSkinBase.java:149)
at com.sun.javafx.scene.control.skin.CellSkinBase$StyleableProperties$1.getStyleableProperty(CellSkinBase.java:138)
at javafx.scene.CssStyleHelper.resetToInitialValues(CssStyleHelper.java:447)
at javafx.scene.CssStyleHelper.createStyleHelper(CssStyleHelper.java:180)
at javafx.scene.Node.reapplyCss(Node.java:8983)
at javafx.scene.Node.impl_reapplyCSS(Node.java:8946)
at javafx.scene.control.Control$1.invalidated(Control.java:300)
at javafx.beans.property.ObjectPropertyBase.markInvalid(ObjectPropertyBase.java:111)
at javafx.beans.property.ObjectPropertyBase.set(ObjectPropertyBase.java:146)
at javafx.css.StyleableObjectProperty.set(StyleableObjectProperty.java:82)
at javafx.scene.control.Control$1.set(Control.java:237)
at javafx.scene.control.Control$1.set(Control.java:220)
at javafx.scene.control.Control.setSkin(Control.java:217)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.recreateCells(TableRowSkinBase.java:673)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.updateCells(TableRowSkinBase.java:499)
at com.sun.javafx.scene.control.skin.TreeTableRowSkin.updateCells(TreeTableRowSkin.java:220)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.checkState(TableRowSkinBase.java:631)
at com.sun.javafx.scene.control.skin.TableRowSkinBase.computePrefHeight(TableRowSkinBase.java:571)
at javafx.scene.control.Control.computePrefHeight(Control.java:547)
at javafx.scene.Parent.prefHeight(Parent.java:935)
at javafx.scene.layout.Region.prefHeight(Region.java:1435)
at com.sun.javafx.scene.control.skin.VirtualFlow.resizeCellSize(VirtualFlow.java:1947)
at com.sun.javafx.scene.control.skin.VirtualFlow.addLeadingCells(VirtualFlow.java:1247)
at com.sun.javafx.scene.control.skin.VirtualFlow.layoutChildren(VirtualFlow.java:1194)
at javafx.scene.Parent.layout(Parent.java:1087)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Parent.layout(Parent.java:1093)
at javafx.scene.Scene.doLayoutPass(Scene.java:552)
at javafx.scene.Scene$ScenePulseListener.pulse(Scene.java:2397)
at com.sun.javafx.tk.Toolkit.lambda$runPulse$29(Toolkit.java:398)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.Toolkit.runPulse(Toolkit.java:397)
at com.sun.javafx.tk.Toolkit.firePulse(Toolkit.java:424)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:518)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:498)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulseFromQueue(QuantumToolkit.java:491)
at com.sun.javafx.tk.quantum.QuantumToolkit.lambda$runToolkit$403(QuantumToolkit.java:319)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
at java.lang.Thread.run(Unknown Source)
有人有指导我调试的想法吗？ 我是否需要放弃某些行的样式？
编辑1经过进一步测试后，它比我想象的要少随机性。 我在过滤器字段中输入一个字母，然后在卡纸前将其删除34次。 如果我使用一系列字母（而不是每次都使用相同的字母），它似乎比34（例如29或31）早于卡纸。因此，我认为每次迭代都不会清除某些内容，但我不知道该怎么做。
我仍然不知道该错误的原因。 我想我找到了一种方法，通过在TreeTableView上使用setRowFactory而不是在setCellFactory上使用setCellFactory和getTreeTableRow()来设置特殊行的样式。 由于Row是同一个对象，所以看起来很奇怪，我只是以不同的方式访问它，但是到目前为止，我还没有使用这种方式的错误。
tableShop.setRowFactory(table-> {
return new TreeTableRow<Product>(){
@Override
public void updateItem(Product pers, boolean empty) {
super.updateItem(pers, empty);
boolean isTopLevel = table.getRoot().getChildren().contains(treeItemProperty().get());
if(pers==null||empty) {
setText(null);
setGraphic(null);
getStyleClass().remove("topLevelRow");
}else {
if(isTopLevel) {
if(!getStyleClass().contains("topLevelRow")) {
getStyleClass().add("topLevelRow");
}
}else {
getStyleClass().remove("topLevelRow");
}
}
}
};
});
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