【发布时间】：2022-01-07 08:24:22
【问题描述】：
我正在创建一个搜索引擎类型的项目，我必须在 JavaFX 中制作 UI 并使用 Apache Lucene 进行查询。我处于 JavaFX 中的 UI 可以完美地自行运行的阶段（无需调用任何 Lucene 方法），并且 Lucene 的查询也可以自行正常运行（在单独的 Java 项目中）。当我尝试通过将 Lucene 对象创建到按下 ENTER 按钮时执行的操作中来将两者结合起来时，它会严重崩溃，并且异常不会令人困惑。
我正在为我的Window 和我的LuceneTester 类和抛出的异常提供代码。
主类：
public class Main extends Application {
@Override
public void start(Stage primaryStage) {
new Window(primaryStage);
}
public static void main(String[] args) {
launch(args);
}
}
窗口类
public class Window{
public Window(Stage primaryStage) {
VBox root = new VBox();
root.getChildren().addAll(setSearch(), setBody());
Scene scene = new Scene(root);
primaryStage.setTitle("The Reuters Search Assistant");
primaryStage.getIcons().add(new Image(getClass().getResourceAsStream("icon.png")));
primaryStage.requestFocus();
primaryStage.setMinWidth(1280);
primaryStage.setMinHeight(720);
primaryStage.setResizable(false);
primaryStage.setScene(scene);
primaryStage.show();
}
private VBox setSearch() {
Label search = new Label("Search");
search.setFont(new Font("arial", 30));
search.setPadding(new Insets(5.0, 5.0, 5.0, 5.0));
search.setAlignment(Pos.CENTER_LEFT);
search.setTextAlignment(TextAlignment.LEFT);
TextField searchBar = new TextField();
searchBar.setFont(new Font("arial", 14));
searchBar.setPromptText("type here");
searchBar.setAlignment(Pos.CENTER_LEFT);
searchBar.setOnKeyPressed(event -> {
if (event.getCode() == KeyCode.ENTER) {
searchAction(searchBar.getText());
}
});
Separator separator = new Separator();
separator.setOrientation(Orientation.HORIZONTAL);
separator.setPadding(new Insets(5.0, 0, 0, 0));
VBox searchPanel = new VBox();
searchPanel.setAlignment(Pos.TOP_LEFT);
searchPanel.setPadding(new Insets(5.0, 5.0, 0 ,5.0));
searchPanel.setSpacing(5.0);
searchPanel.fillWidthProperty();
searchPanel.getChildren().addAll(search, searchBar, separator);
return searchPanel;
}
private HBox setBody() {
Button addBtn = new Button("Add Article");
addBtn.setFont(new Font("arial", 20));
addBtn.setMinWidth(170);
addBtn.setOnMouseClicked(e -> {
addArticleAction();
});
Button editBtn = new Button("Edit Article");
editBtn.setFont(new Font("arial", 20));
editBtn.setMinWidth(170);
editBtn.setOnMouseClicked(e -> {
editArticleAction();
});
Button delBtn = new Button("Delete Article");
delBtn.setFont(new Font("arial", 20));
delBtn.setMinWidth(170);
delBtn.setOnMouseClicked(e -> {
delArticleAction();
});
VBox buttonsBox = new VBox();
buttonsBox.setAlignment(Pos.TOP_CENTER);
buttonsBox.setMinWidth(200);
buttonsBox.setPadding(new Insets(15.0, 5.0, 5.0, 5.0));
buttonsBox.setSpacing(20.0);
buttonsBox.getChildren().addAll(addBtn, editBtn, delBtn);
Separator separator = new Separator();
separator.setOrientation(Orientation.VERTICAL);
ListView listView = new ListView();
listView.setMinWidth(1050);
listView.setMinHeight(574);
VBox listViewBox = new VBox();
listViewBox.setPadding(new Insets(5.0, 0, 0, 1.0));
listViewBox.getChildren().add(listView);
HBox bodyPanel = new HBox();
bodyPanel.getChildren().addAll(buttonsBox, separator, listViewBox);
return bodyPanel;
}
private void searchAction(String searchString) {
System.out.println("Searching for : " + searchString);
// Here is where the exception occurs.
LuceneTester search = new LuceneTester(searchString);
}
private void addArticleAction() {
System.out.println("add article");
}
private void editArticleAction() {
System.out.println("edit article");
}
private void delArticleAction() {
System.out.println("delete article");
}
}
LuceneTester 类
public class LuceneTester {
String indexDir = "C:\\Users\\stefa\\eclipse-workspace\\TReSA\\index";
String dataDir = "C:\\Users\\stefa\\eclipse-workspace\\TReSA\\data";
Indexer indexer;
Searcher searcher;
public LuceneTester(String searchString) {
try {
this.createIndex();
this.search(searchString);
} catch (IOException e) {
e.printStackTrace();
} catch (ParseException e) {
e.printStackTrace();
}
}
private void createIndex() throws IOException {
indexer = new Indexer(indexDir);
int numIndexed;
long startTime = System.currentTimeMillis();
numIndexed = indexer.createIndex(dataDir, new TextFileFilter());
long endTime = System.currentTimeMillis();
indexer.close();
System.out.println(numIndexed + " File(s) indexed, time taken: " + (endTime-startTime) + " ms");
}
private void search(String searchQuery) throws IOException, ParseException {
searcher = new Searcher(indexDir);
long startTime = System.currentTimeMillis();
TopDocs hits = searcher.search(searchQuery);
long endTime = System.currentTimeMillis();
System.out.println(hits.totalHits +" found. Time : " + (endTime - startTime) + " ms");
for(ScoreDoc scoreDoc : hits.scoreDocs) {
Document doc = searcher.getDocument(scoreDoc);
System.out.println("File: " + doc.get(LuceneConstants.FILE_PATH));
}
}
}
例外
Exception in thread "JavaFX Application Thread" java.lang.NoClassDefFoundError: org/apache/lucene/queryparser/classic/ParseException
at com.TReSA.main.Window.searchAction(Window.java:116)
at com.TReSA.main.Window.lambda$0(Window.java:52)
at javafx.base/com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at javafx.base/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:234)
at javafx.base/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at javafx.base/com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at javafx.base/com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.base/javafx.event.Event.fireEvent(Event.java:198)
at javafx.graphics/javafx.scene.Scene$KeyHandler.process(Scene.java:4105)
at javafx.graphics/javafx.scene.Scene.processKeyEvent(Scene.java:2156)
at javafx.graphics/javafx.scene.Scene$ScenePeerListener.keyEvent(Scene.java:2630)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:218)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:150)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleKeyEvent$1(GlassViewEventHandler.java:250)
at javafx.graphics/com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:424)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler.handleKeyEvent(GlassViewEventHandler.java:249)
at javafx.graphics/com.sun.glass.ui.View.handleKeyEvent(View.java:548)
at javafx.graphics/com.sun.glass.ui.View.notifyKey(View.java:972)
at javafx.graphics/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:184)
at java.base/java.lang.Thread.run(Thread.java:833)
Caused by: java.lang.ClassNotFoundException: org.apache.lucene.queryparser.classic.ParseException
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:520)
... 29 more
提前致谢。
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