用户无法输入文本，索引越界异常
User Cannot Enter Text, Index Out Of Bounds Exception
我的代码运行了，但是当用户在文本字段中输入文本时，我收到了越界异常。我认为这与我给空框一个值的这行代码有关：int express = (str != null && !"".equals(str)) ? Integer.parseInt(str) : -1; 但我不确定。有没有不同的方法来做到这一点？这是代码：
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.image.Image;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;
import javafx.scene.image.ImageView;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedList;
import java.util.concurrent.atomic.AtomicReference;
public class Main extends Application {
@Override
public void start(Stage primaryStage) {
ArrayList<Integer> deck;
deck = new ArrayList<>();
int i = 1;
while(i < 52){
deck.add(i);
i++;
}
final AtomicReference<String> result = new AtomicReference<>("go.");
Collections.shuffle(deck);
BorderPane pane = new BorderPane();
HBox top = new HBox(10);
Label display = new Label(result.toString());
Button btShuffle = new Button("Shuffle");
top.getChildren().add(display);
top.getChildren().add(btShuffle);
HBox center = new HBox(10);
Card card1 = new Card(deck.get(0));
center.getChildren().add(card1);
Card card2 = new Card(deck.get(1));
center.getChildren().add(card2);
Card card3 = new Card(deck.get(12));
center.getChildren().add(card3);
Card card4 = new Card(deck.get(14));
center.getChildren().add(card4);
btShuffle.setOnAction(
e -> {
Collections.shuffle(deck);
center.getChildren().clear();
center.getChildren().add(new Card(deck.get(0)));
center.getChildren().add(new Card(deck.get(1)));
center.getChildren().add(new Card(deck.get(2)));
center.getChildren().add(new Card(deck.get(3)));
});
HBox bottom = new HBox(10);
Label expression = new Label("Please Enter the expression: ");
TextField tfExpress = new TextField();
LinkedList<Object> expInput = new LinkedList<>();
ArrayList<Character> signs = new ArrayList<>();
signs.add('/');
signs.add('+');
signs.add('(');
signs.add(')');
signs.add('-');
signs.add('^');
signs.add('*');
signs.add('%');
String str = tfExpress.getText();
char tempStor[] = str.toCharArray();
for(char c: tempStor){
expInput.add(c);
}
int express = (str != null && !"".equals(str)) ? Integer.parseInt(str) : -1;
expInput.removeIf(p-> p.equals(signs));
Button btVerify = new Button("Verify");
bottom.getChildren().add(expression);
bottom.getChildren().add(tfExpress);
bottom.getChildren().add(btVerify);
btVerify.setOnAction(
(ActionEvent e) -> {
if(card1.CardValue() == (int)expInput.get(0)
&& card2.CardValue() == (int)expInput.get(1)
&& card3.CardValue() == (int)expInput.get(2)
&& card4.CardValue() == (int)expInput.get(3)){
if(express == 24){
result.set("Correct");
}
else
result.set("Incorrect");
}
else
result.set("The numbers in the expression don't "
+ "match the numbers in the set.");
});
pane.setTop(top);
pane.setCenter(center);
pane.setBottom(bottom);
Scene scene = new Scene(pane);
primaryStage.setTitle("24 card game");
primaryStage.setScene(scene);
primaryStage.show();
}
public class Card extends Pane {
public int cardVal;
Card(int card){
Image cardImage;
cardImage = new Image("card/"+ card +".png");
getChildren().add(new ImageView(cardImage));
cardVal = card;
}
public int CardValue(){
int card = 0;
if(cardVal <= 13){
card = cardVal;
}
else if(cardVal > 13 && cardVal <= 26){
card = cardVal - 13;
}
else if(cardVal > 26 && cardVal <= 39){
card = cardVal - 26;
}
else if(cardVal > 39 && cardVal <= 52){
card = cardVal - 39;
}
return card;
}
}
public static void main(String[] args) {
launch(args);
}
}
这里是例外：
Exception in thread "JavaFX Application Thread" java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.LinkedList.checkElementIndex(LinkedList.java:555)
at java.util.LinkedList.get(LinkedList.java:476)
at Main.lambda$start(Main.java:109)
at Main$$Lambda/1787879.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Node.fireEvent(Node.java:8216)
at javafx.scene.control.Button.fire(Button.java:185)
at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:182)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase.handle(BehaviorSkinBase.java:96)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase.handle(BehaviorSkinBase.java:89)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3724)
at javafx.scene.Scene$MouseHandler.access00(Scene.java:3452)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1728)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2461)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:348)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:273)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:382)
at com.sun.glass.ui.View.handleMouseEvent(View.java:553)
at com.sun.glass.ui.View.notifyMouse(View.java:925)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null1(WinApplication.java:102)
at com.sun.glass.ui.win.WinApplication$$Lambda/2075313.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)
故障发生在
btVerify.setOnAction(
(ActionEvent e) -> {
if(card1.CardValue() == (int)expInput.get(0)
上面的某些行创建了一个新的 LinkedList，因此其中没有任何值。这导致异常。
编辑：作为对一些评论的回复。可能的解决方案如下所示：
（无需进一步必要的重构；））
final
btVerify.setOnAction(
(ActionEvent e) -> {
LinkedList<Character> expInput = new LinkedList<Character>();
for(char c: tfExpress.getText().toCharArray()){
expInput.add(c);
}
if(card1.CardValue() == Integer.valueOf(expInput.get(0))
&& card2.CardValue() == Integer.valueOf(expInput.get(1) )
&& card3.CardValue() == Integer.valueOf(expInput.get(2))
&& card4.CardValue() == Integer.valueOf(expInput.get(3))){
if(express == 24){
result.set("Correct");
}
else
result.set("Incorrect");
}
else
result.set("The numbers in the expression don't "
+ "match the numbers in the set.");
});
我的代码运行了，但是当用户在文本字段中输入文本时，我收到了越界异常。我认为这与我给空框一个值的这行代码有关：int express = (str != null && !"".equals(str)) ? Integer.parseInt(str) : -1; 但我不确定。有没有不同的方法来做到这一点？这是代码：
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.image.Image;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;
import javafx.scene.image.ImageView;
import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedList;
import java.util.concurrent.atomic.AtomicReference;
public class Main extends Application {
@Override
public void start(Stage primaryStage) {
ArrayList<Integer> deck;
deck = new ArrayList<>();
int i = 1;
while(i < 52){
deck.add(i);
i++;
}
final AtomicReference<String> result = new AtomicReference<>("go.");
Collections.shuffle(deck);
BorderPane pane = new BorderPane();
HBox top = new HBox(10);
Label display = new Label(result.toString());
Button btShuffle = new Button("Shuffle");
top.getChildren().add(display);
top.getChildren().add(btShuffle);
HBox center = new HBox(10);
Card card1 = new Card(deck.get(0));
center.getChildren().add(card1);
Card card2 = new Card(deck.get(1));
center.getChildren().add(card2);
Card card3 = new Card(deck.get(12));
center.getChildren().add(card3);
Card card4 = new Card(deck.get(14));
center.getChildren().add(card4);
btShuffle.setOnAction(
e -> {
Collections.shuffle(deck);
center.getChildren().clear();
center.getChildren().add(new Card(deck.get(0)));
center.getChildren().add(new Card(deck.get(1)));
center.getChildren().add(new Card(deck.get(2)));
center.getChildren().add(new Card(deck.get(3)));
});
HBox bottom = new HBox(10);
Label expression = new Label("Please Enter the expression: ");
TextField tfExpress = new TextField();
LinkedList<Object> expInput = new LinkedList<>();
ArrayList<Character> signs = new ArrayList<>();
signs.add('/');
signs.add('+');
signs.add('(');
signs.add(')');
signs.add('-');
signs.add('^');
signs.add('*');
signs.add('%');
String str = tfExpress.getText();
char tempStor[] = str.toCharArray();
for(char c: tempStor){
expInput.add(c);
}
int express = (str != null && !"".equals(str)) ? Integer.parseInt(str) : -1;
expInput.removeIf(p-> p.equals(signs));
Button btVerify = new Button("Verify");
bottom.getChildren().add(expression);
bottom.getChildren().add(tfExpress);
bottom.getChildren().add(btVerify);
btVerify.setOnAction(
(ActionEvent e) -> {
if(card1.CardValue() == (int)expInput.get(0)
&& card2.CardValue() == (int)expInput.get(1)
&& card3.CardValue() == (int)expInput.get(2)
&& card4.CardValue() == (int)expInput.get(3)){
if(express == 24){
result.set("Correct");
}
else
result.set("Incorrect");
}
else
result.set("The numbers in the expression don't "
+ "match the numbers in the set.");
});
pane.setTop(top);
pane.setCenter(center);
pane.setBottom(bottom);
Scene scene = new Scene(pane);
primaryStage.setTitle("24 card game");
primaryStage.setScene(scene);
primaryStage.show();
}
public class Card extends Pane {
public int cardVal;
Card(int card){
Image cardImage;
cardImage = new Image("card/"+ card +".png");
getChildren().add(new ImageView(cardImage));
cardVal = card;
}
public int CardValue(){
int card = 0;
if(cardVal <= 13){
card = cardVal;
}
else if(cardVal > 13 && cardVal <= 26){
card = cardVal - 13;
}
else if(cardVal > 26 && cardVal <= 39){
card = cardVal - 26;
}
else if(cardVal > 39 && cardVal <= 52){
card = cardVal - 39;
}
return card;
}
}
public static void main(String[] args) {
launch(args);
}
}
这里是例外：
Exception in thread "JavaFX Application Thread" java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.LinkedList.checkElementIndex(LinkedList.java:555)
at java.util.LinkedList.get(LinkedList.java:476)
at Main.lambda$start(Main.java:109)
at Main$$Lambda/1787879.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Node.fireEvent(Node.java:8216)
at javafx.scene.control.Button.fire(Button.java:185)
at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:182)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase.handle(BehaviorSkinBase.java:96)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase.handle(BehaviorSkinBase.java:89)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.event.Event.fireEvent(Event.java:198)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3724)
at javafx.scene.Scene$MouseHandler.access00(Scene.java:3452)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1728)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2461)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:348)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:273)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:382)
at com.sun.glass.ui.View.handleMouseEvent(View.java:553)
at com.sun.glass.ui.View.notifyMouse(View.java:925)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null1(WinApplication.java:102)
at com.sun.glass.ui.win.WinApplication$$Lambda/2075313.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)
故障发生在
btVerify.setOnAction(
(ActionEvent e) -> {
if(card1.CardValue() == (int)expInput.get(0)
上面的某些行创建了一个新的 LinkedList，因此其中没有任何值。这导致异常。
编辑：作为对一些评论的回复。可能的解决方案如下所示： （无需进一步必要的重构；））
final
btVerify.setOnAction(
(ActionEvent e) -> {
LinkedList<Character> expInput = new LinkedList<Character>();
for(char c: tfExpress.getText().toCharArray()){
expInput.add(c);
}
if(card1.CardValue() == Integer.valueOf(expInput.get(0))
&& card2.CardValue() == Integer.valueOf(expInput.get(1) )
&& card3.CardValue() == Integer.valueOf(expInput.get(2))
&& card4.CardValue() == Integer.valueOf(expInput.get(3))){
if(express == 24){
result.set("Correct");
}
else
result.set("Incorrect");
}
else
result.set("The numbers in the expression don't "
+ "match the numbers in the set.");
});