I've been trying to understand what the issue is exactly, but whatever I do doesn't seem to work.
I have a text file that lists names along with numbers, seperated by a colon.
An example of this is:
Betty Ross:52
Angie Scotts:29
Michael Rosen:72
The list is very long and comprises over 10,000 lines.
public class PeopleIds {
public static int UNDEFINED_ID = -1;
private static HashMap<String, Integer> people;
public static void initialize() {
people = new HashMap<String, Integer>();
System.out.println(new File("res/ids/people_ids.txt").exists());
try {
Files.lines(Paths.get("res/ids/people_ids.txt")).forEach(s -> {
people.put(s.replaceAll(":.*", "").trim(), Integer.parseInt(s.replaceAll(".*:", "")));
});
} catch (IOException e) {
System.out.println("Unable to read specified file.");
e.printStackTrace();
}
}
public static int getId(final String name) {
final Integer id = people.get(name);
return id != null ? id : UNDEFINED_ID;
}
}
I call the initialize method from a GUIController class:
public class GUIController implements Initializable {
#FXML
private TableView<PersonData> personTable;
#FXML
private TableColumn<PersonData, String> name;
#FXML
private TableColumn<PersonData, Integer> limit;
#FXML
private TextField searchInput;
#FXML
private ImageView personIcon;
private Image undefinedIcon;
private PersonIcon icon;
private ObservableList<PersonData> data;
#Override
public void initialize(URL location, ResourceBundle resources) {
PeopleIds.initialize();
undefinedIcon = new Image(getClass().getResourceAsStream("/ids/no.png"));
name.setCellValueFactory(new PropertyValueFactory<PersonData, String>("name"));
limit.setCellValueFactory(new PropertyValueFactory<PersonData, Integer>("limit"));
data = PriceData.getData();
personTable.setPeople(data);
searchInput.textProperty().addListener((ov, oldValue, newValue) -> {
final String input = searchInput.getText();
if (input.length() == 0) return;
searchInput.setText(input.substring(0, 1).toUpperCase() + input.substring(1).toLowerCase());
filterSearch();
});
}
}
When I call it from this class with PeopleIds.initialize(), an exception is thrown, telling me that there was an exception in the application start method.
Here is what was logged in its entirety:
Exception in Application start method
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(Unknown Source)
at com.sun.javafx.application.LauncherImpl.launchApplication(Unknown Source)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.launcher.LauncherHelper$FXHelper.main(Unknown Source)
Caused by: java.lang.RuntimeException: Exception in Application start method
at com.sun.javafx.application.LauncherImpl.launchApplication1(Unknown Source)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$156(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: javafx.fxml.LoadException:
/C:/Confidential/bin/base/PersonGUI.fxml
at javafx.fxml.FXMLLoader.constructLoadException(Unknown Source)
at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
at javafx.fxml.FXMLLoader.load(Unknown Source)
at base.PersonGUI.start(PersonGUI.java:13)
at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$163(Unknown Source)
at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$176(Unknown Source)
at com.sun.javafx.application.PlatformImpl.lambda$null$174(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.application.PlatformImpl.lambda$runLater$175(Unknown Source)
at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$149(Unknown Source)
... 1 more
Caused by: java.io.UncheckedIOException: java.nio.charset.MalformedInputException: Input length = 1
at java.io.BufferedReader$1.hasNext(Unknown Source)
at java.util.Iterator.forEachRemaining(Unknown Source)
at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Unknown Source)
at java.util.stream.ReferencePipeline$Head.forEach(Unknown Source)
at base.PeopleIds.initialize(PeopleIds.java:17)
at base.GUIController.initialize(GUIController.java:36)
... 18 more
Caused by: java.nio.charset.MalformedInputException: Input length = 1
at java.nio.charset.CoderResult.throwException(Unknown Source)
at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
at sun.nio.cs.StreamDecoder.read(Unknown Source)
at java.io.InputStreamReader.read(Unknown Source)
at java.io.BufferedReader.fill(Unknown Source)
at java.io.BufferedReader.readLine(Unknown Source)
at java.io.BufferedReader.readLine(Unknown Source)
... 24 more
Exception running application base.PersonGUI
I'm not sure what is going on here? I've looked into it and people have said to move the fxml file (the one that is used to format the content and is linked with the GUIController to the same package as the Main class, however it already is.
I've been wrestling with this issue for days to no avail. Do any of you have past experiences with this issue? If so, how did you resolve it? Thanks a lot.
If there is an Exception while the file is being read, not when opening the file, an unchecked exception is thrown for the Files.lines stream operation (Stream.forEach doesn't have a throws clause).
This happens here
Files.lines(Paths.get("res/ids/people_ids.txt")).forEach(s -> {
people.put(s.replaceAll(":.*", "").trim(), Integer.parseInt(s.replaceAll(".*:", "")));
});
, which you can easily see in the stacktrace:
Caused by: java.io.UncheckedIOException: java.nio.charset.MalformedInputException: Input length = 1
(This is caused by the wrong Charset being used, see Files.readAllBytes vs Files.lines getting MalformedInputException )
You don't catch this kind of exception with your catch clause:
} catch (IOException e) {
You need to use
} catch (Exception e) {
to catch the unchecked exceptions too.
Related
I have created custom entry processor for updating map entries by extending AbstractEntryProcessor.
When my app is running in a cluster on two instances, and the entry processor is executed I receive following exception:
com.hazelcast.nio.serialization.HazelcastSerializationException: Failed to serialize 'com.hazelcast.spi.impl.operationservice.impl.operations.Backup'
at com.hazelcast.internal.serialization.impl.SerializationUtil.handleSerializeException(SerializationUtil.java:73)
at com.hazelcast.internal.serialization.impl.AbstractSerializationService.toBytes(AbstractSerializationService.java:143)
at com.hazelcast.internal.serialization.impl.AbstractSerializationService.toBytes(AbstractSerializationService.java:124)
at com.hazelcast.spi.impl.operationservice.impl.OperationServiceImpl.send(OperationServiceImpl.java:406)
at com.hazelcast.spi.impl.operationservice.impl.OperationBackupHandler.sendSingleBackup(OperationBackupHandler.java:187)
at com.hazelcast.spi.impl.operationservice.impl.OperationBackupHandler.makeBackups(OperationBackupHandler.java:159)
at com.hazelcast.spi.impl.operationservice.impl.OperationBackupHandler.backup(OperationBackupHandler.java:78)
at com.hazelcast.spi.impl.operationservice.impl.OperationRunnerImpl.sendBackup(OperationRunnerImpl.java:270)
at com.hazelcast.spi.impl.operationservice.impl.OperationRunnerImpl.handleResponse(OperationRunnerImpl.java:253)
at com.hazelcast.spi.impl.operationservice.impl.OperationRunnerImpl.run(OperationRunnerImpl.java:182)
at com.hazelcast.spi.impl.operationexecutor.impl.OperationThread.process(OperationThread.java:122)
at com.hazelcast.spi.impl.operationexecutor.impl.OperationThread.run(OperationThread.java:102)
Caused by: com.hazelcast.nio.serialization.HazelcastSerializationException: Failed to serialize 'com.hazelcast.map.impl.operation.PartitionWideEntryWithPredicateBackupOperation'
at com.hazelcast.internal.serialization.impl.SerializationUtil.handleSerializeException(SerializationUtil.java:73)
at com.hazelcast.internal.serialization.impl.AbstractSerializationService.writeObject(AbstractSerializationService.java:201)
at com.hazelcast.internal.serialization.impl.ByteArrayObjectDataOutput.writeObject(ByteArrayObjectDataOutput.java:371)
at com.hazelcast.spi.impl.operationservice.impl.operations.Backup.writeInternal(Backup.java:222)
at com.hazelcast.spi.Operation.writeData(Operation.java:472)
at com.hazelcast.internal.serialization.impl.DataSerializableSerializer.write(DataSerializableSerializer.java:161)
at com.hazelcast.internal.serialization.impl.DataSerializableSerializer.write(DataSerializableSerializer.java:52)
at com.hazelcast.internal.serialization.impl.StreamSerializerAdapter.write(StreamSerializerAdapter.java:41)
at com.hazelcast.internal.serialization.impl.AbstractSerializationService.toBytes(AbstractSerializationService.java:140)
... 10 common frames omitted
Caused by: com.hazelcast.nio.serialization.HazelcastSerializationException: Failed to serialize 'com.hazelcast.map.AbstractEntryProcessor$EntryBackupProcessorImpl'
at com.hazelcast.internal.serialization.impl.SerializationUtil.handleSerializeException(SerializationUtil.java:73)
at com.hazelcast.internal.serialization.impl.AbstractSerializationService.writeObject(AbstractSerializationService.java:201)
at com.hazelcast.internal.serialization.impl.ByteArrayObjectDataOutput.writeObject(ByteArrayObjectDataOutput.java:371)
at com.hazelcast.map.impl.operation.PartitionWideEntryBackupOperation.writeInternal(PartitionWideEntryBackupOperation.java:98)
at com.hazelcast.map.impl.operation.PartitionWideEntryWithPredicateBackupOperation.writeInternal(PartitionWideEntryWithPredicateBackupOperation.java:51)
at com.hazelcast.spi.Operation.writeData(Operation.java:472)
at com.hazelcast.internal.serialization.impl.DataSerializableSerializer.write(DataSerializableSerializer.java:161)
at com.hazelcast.internal.serialization.impl.DataSerializableSerializer.write(DataSerializableSerializer.java:52)
at com.hazelcast.internal.serialization.impl.StreamSerializerAdapter.write(StreamSerializerAdapter.java:41)
at com.hazelcast.internal.serialization.impl.AbstractSerializationService.writeObject(AbstractSerializationService.java:199)
... 17 common frames omitted
Caused by: java.util.ConcurrentModificationException: null
at java.util.ArrayList.writeObject(Unknown Source)
at sun.reflect.GeneratedMethodAccessor143.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at java.util.ArrayList.writeObject(Unknown Source)
at sun.reflect.GeneratedMethodAccessor143.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at java.io.ObjectStreamClass.invokeWriteObject(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at com.hazelcast.internal.serialization.impl.JavaDefaultSerializers$JavaSerializer.write(JavaDefaultSerializers.java:242)
at com.hazelcast.internal.serialization.impl.StreamSerializerAdapter.write(StreamSerializerAdapter.java:41)
at com.hazelcast.internal.serialization.impl.AbstractSerializationService.writeObject(AbstractSerializationService.java:199)
... 25 common frames omitted
My entry processor is look like this:
public class HRUpdateRacesWithEntriesProcessor extends AbstractEntryProcessor<HRMeeting.HRMeetingKey, HRMeeting> {
private List<HRRace> races;
private Date date;
public HRUpdateRacesWithEntriesProcessor(List<HRRace> races, Date date) {
this.races = races;
this.date = date;
}
#Override
public Object process(Map.Entry<HRMeeting.HRMeetingKey, HRMeeting> entry) {
HRMeeting meeting = entry.getValue();
races.stream()
.filter(race -> entry.getKey().equals(new HRMeeting.HRMeetingKey(race.getMeetingDate(), race.getCourseId())))
.forEach(newRace -> {
Optional<HRRace> matchedRace =
meeting.getRaces().stream().filter(origin -> origin.getKey().equals(newRace.getKey())).findFirst();
if (newRace.getEntries() != null && matchedRace.isPresent()) {
newRace.setUpdateDate(date);
newRace.getEntries().stream()
.filter(hrEntry -> matchedRace.get().getEntries().stream().map(el -> el.getKey())
.collect(Collectors.toList()).contains(hrEntry.getKey()))
.forEach(hrEntry -> hrEntry.setUpdateDate(date));
matchedRace.get().getEntries().retainAll(newRace.getEntries());
newRace.getEntries().addAll(matchedRace.get().getEntries());
}
meeting.getRaces()
.removeIf(hrRace -> matchedRace.isPresent() && matchedRace.get().getKey().equals(hrRace.getKey()));
meeting.getRaces().add(newRace);
});
entry.setValue(meeting);
return null;
}
}
For serialization my entites implements java Serializible. Is is can be reason of the issue?
I am using hazelcast-3.8-SNAPSHOT
Please, help me to solve it.
It might be a simple problem. I met the same error when tried to put an Object to IMap in Hazelcast. In my case, the object, which I try to put, wasn't implements Serializable.
So, I think you should check you did implements Serializable in "com.hazelcast.spi.impl.operationservice.impl.operations.Backup" like
public class Backup implements Serializable {
...
}
I think your problem is that somehow (it actually hard to follow the stream flow) capture content from your EntryProcessor implementation and because of that it is tried to be serialized using Serializable. Anyhow DataSerializable / IdentifiedDataSerializable is not java.util.Serializable to prevent unexpected serialization (like in your case) from happening :)
My guess is the date:
.forEach(hrEntry -> hrEntry.setUpdateDate(date));
I hope this helps, you might have to look for the actually captured value.
In Java, sometimes I get an exception parsing user input. Instead of printing a stack trace, I want it to "cleanly" redirect the output to a string. Example (uses LuaJ):
Exception:
Exception in thread "Thread-3" org.luaj.vm2.LuaError: [string "jhkfchyufjhdnxvk,gh'bnmcvk,fvjmfk,xdcfsdkckucfdxfds,ie(); "]:1: unfinished string
at org.luaj.vm2.compiler.LexState.lexerror(Unknown Source)
at org.luaj.vm2.compiler.LexState.read_string(Unknown Source)
at org.luaj.vm2.compiler.LexState.llex(Unknown Source)
at org.luaj.vm2.compiler.LexState.next(Unknown Source)
at org.luaj.vm2.compiler.LexState.str_checkname(Unknown Source)
at org.luaj.vm2.compiler.LexState.singlevar(Unknown Source)
at org.luaj.vm2.compiler.LexState.primaryexp(Unknown Source)
at org.luaj.vm2.compiler.LexState.suffixedexp(Unknown Source)
at org.luaj.vm2.compiler.LexState.assignment(Unknown Source)
at org.luaj.vm2.compiler.LexState.exprstat(Unknown Source)
at org.luaj.vm2.compiler.LexState.statement(Unknown Source)
at org.luaj.vm2.compiler.LexState.statlist(Unknown Source)
at org.luaj.vm2.compiler.LexState.mainfunc(Unknown Source)
at org.luaj.vm2.compiler.LuaC.luaY_parser(Unknown Source)
at org.luaj.vm2.compiler.LuaC.compile(Unknown Source)
at org.luaj.vm2.Globals.compilePrototype(Unknown Source)
at org.luaj.vm2.Globals.loadPrototype(Unknown Source)
at org.luaj.vm2.Globals.load(Unknown Source)
at org.luaj.vm2.Globals.load(Unknown Source)
at org.luaj.vm2.Globals.load(Unknown Source)
at net.snugglesstuff.LeoBot.LuaThread.run(LuaThread.java:25)
What the output should be:
[string "jhkfchyufjhdnxvk,gh'bnmcvk,fvjmfk,xdcfsdkckucfdxfds,ie(); "]:1: unfinished string
You can catch the exception and print exception.getMessage().
try {
... parsing code ...
}
catch (Exception exc) { // change this to catch the specific type of exceptions relevant to the parsing
System.out.println(exc.getMessage()); // or redirect the message to a file
}
I am trying to make a small application where when a player clicks a button it gets the values from a file, and then adds to it if the bank number is in the file and if not, makes a new bank number with the amount with it:
package application;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.PrintStream;
import java.util.Scanner;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.fxml.FXMLLoader;
import javafx.stage.Stage;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
public class Main extends Application {
#Override
public void start(Stage primaryStage) {
try {
//BorderPane root = new BorderPane();
Parent root = FXMLLoader.load(getClass().getResource("Root.fxml"));
Scene scene = new Scene(root,400,400);
scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.show();
} catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
launch(args);
}
#FXML
private TextField banknumber;
#FXML
private TextField original;
#FXML
private TextField deposited;
#FXML
private TextField output;
#FXML
protected void onClick(ActionEvent event) throws FileNotFoundException{
PrintStream diskWriter = new PrintStream(new File("accounts.txt"));
Scanner diskReader = new Scanner(new File("accounts.txt"));
int origbal;
int addtobal = Integer.parseInt(deposited.getText());
String number = banknumber.getText();
if(diskReader.next().equals(number)){
origbal = diskReader.nextInt();
int newbal = origbal+addtobal;
diskWriter.println("Number: " + number + " Total: " + newbal);
}
else{
origbal = Integer.parseInt(original.getText());
int newbal = origbal+addtobal;
diskWriter.println("Number: " + number + " Total: " + newbal);
}
int newbal = origbal+addtobal;
output.setText("You have added $" + addtobal + " to bank number: " + number + "for a total of $" + newbal);
diskWriter.close();
}
}
I am getting an error though and I don't know what is wrong with it (The line numbers match up with the paste bin):
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
at javafx.event.Event.fireEvent(Unknown Source)
at javafx.scene.Node.fireEvent(Unknown Source)
at javafx.scene.control.Button.fire(Unknown Source)
at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(Unknown Source)
at com.sun.javafx.scene.control.skin.SkinBase$4.handle(Unknown Source)
at com.sun.javafx.scene.control.skin.SkinBase$4.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEventImpl(Unknown Source)
at com.sun.javafx.event.EventUtil.fireEvent(Unknown Source)
at javafx.event.Event.fireEvent(Unknown Source)
at javafx.scene.Scene$MouseHandler.process(Unknown Source)
at javafx.scene.Scene$MouseHandler.process(Unknown Source)
at javafx.scene.Scene$MouseHandler.access$1900(Unknown Source)
at javafx.scene.Scene.impl_processMouseEvent(Unknown Source)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Unknown Source)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(Unknown Source)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(Unknown Source)
at com.sun.glass.ui.View.handleMouseEvent(Unknown Source)
at com.sun.glass.ui.View.notifyMouse(Unknown Source)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access$100(Unknown Source)
at com.sun.glass.ui.win.WinApplication$3$1.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.reflect.misc.Trampoline.invoke(Unknown Source)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at sun.reflect.misc.MethodUtil.invoke(Unknown Source)
... 45 more
Caused by: java.util.NoSuchElementException
at java.util.Scanner.throwFor(Unknown Source)
at java.util.Scanner.next(Unknown Source)
at application.Main.onClick(Main.java:54)
... 54 more
The file name you are using in the code is "accounts", not "accounts.txt". Also, I don't see a button being defined.
After fixing the path name
Now the Scanner complains (in line 54) that next() is called although there is no next token to be scanned. Normally, one calls `hasNext()? and proceeds only if this returns true.
However, the idea of writing a file and reading from it before writing has been completed (i.e., close() has been called) is a no-no.
I'm not sure what you want to achieve with your code, so I can't really suggest an improvement.
I would suggest using java.util.properties which loads properties from a file into a HashMap and allows you to pull values.
Assuming "accounts.txt" is of form
banknumber1=origbal1
banknumber2=origbal2
#FXML
protected void onClick(ActionEvent event) throws FileNotFoundException{
Properties p = new Properties();
InputStream is = new InputStream("accounts.txt");
p.load(is);
is.close();
String number = banknumber.getText();
String origbal = p.getProperty(number);
int addtobal = Integer.parseInt(deposited.getText());
if (origbal != null)
p.setProperty(number, Integer.parseInt(origbal) + addtobal);
OutputStream os = new OutputStream("accounts.txt");
p.store(os);
os.close();
}
Say for example, if in a program you get a null-pointer error for adding a piece of code to your which program makes the program run fine but without that piece of code the program doesn't work as expected, would it be a good idea to allow the null-pointer error to happen, if so, is there any way of catching it before it displays onto the console. 1 way I am aware of is, using try and catch but in my past experience this hasn't worked, my attempt at using this might be wrong, but this is how I tried it.
try {
// line / s of code to catch the error from
} catch (java.lang.NullPointerException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
edited: The list of error i am getting:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at playAGame.endGameResult(playAGame.java:204)
at playAGame.checkingWinner(playAGame.java:159)
at playAGame.callCheckWinner(playAGame.java:179)
at playAGame.moveSetup(playAGame.java:66)
at playAGame$1.actionPerformed(playAGame.java:52)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$200(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
this is because of this line: button = new JButton[button.length][button.length];
I am creating a TicTacToe game and if I remove that line from my code, the game won't work properly.
edited: I believe this is one of the lines providing the null pointer, correct me if I am wrong. Basically, I have created a method checking if three given buttons have the value X, if it does then trigger the win variable to true. This is how I am checking if someone has won the TicTacToe game.
public void checkingWinner(JButton button1, JButton button2, JButton button3) {
if(buttonA.getText().equals(buttonB.getText()) && buttonB.getText().equals(buttonC.getText()) && buttonA.getText().equals("X"))
{
win = true;
System.out.pl("winner is X");
}
It's hard to tell without seeing the whole code, but it might be the case that the initialization you're doing of the array is throwing an exception since it's the first time it's being initialized, during which time it is being referenced.
If that's the case, you should solve this by using a constant for the width and height instead of self reference:
public static final int HEIGHT = ...;
public static final int WIDTH = ...;
...
button = new JButton[HEIGHT][WIDTH];
Are you sure that the line/s of code are throwing a NullPointerException? Because it works for me.
public class Main {
static String a;
public static void main(String args[]) {
try {
a.charAt(0);
} catch (java.lang.NullPointerException e) {
System.out.println("Thrown");
e.printStackTrace();
}
}
}
I have written a test program that makes a Derby connection and creates the necessary tables if they do not exist. But once I run the programme I can't rerun it again because the exception I have brought. I think that I should add a finilize method to the current singletone class and close the connection there. Is it the solution?
But anyway I consider the possiblity of the program crash and exiting from the program in an abnormal manner. In that case how can I force to close the other instances of the connection to the database safely and make my own connection?
public class DBTest {
public static void main(String[] args) {
DBConnection.getInstance();
}
}
public class DBConnection {
private static DBConnection ourInstance = new DBConnection();
private Connection connection;
public static DBConnection getInstance() {
return ourInstance;
}
private DBConnection() {
String driver = "org.apache.derby.jdbc.EmbeddedDriver";
String dbName="C:/Users/Puk/IdeaProjects/DerbyTest/database/Ablauf";
String connectionURL = "jdbc:derby:" + dbName + ";create=true";
try {
Class.forName(driver);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
try {
connection = DriverManager.getConnection(connectionURL);
} catch (SQLException e) {
e.printStackTrace();
}
createTables();
}
private void createTables(){
Statement s;
try {
s = connection.createStatement();
s.execute("CREATE TABLE category ( id SMALLINT NOT NULL GENERATED ALWAYS AS IDENTITY \n" +
"\t(START WITH 0, INCREMENT BY 1), title VARCHAR(100))");
} catch (SQLException e) {
e.printStackTrace();
}
}
}
java.sql.SQLException: Failed to start database 'C:/Users/Puk/IdeaProjects/DerbyTest/database/Ablauf' with class loader sun.misc.Launcher$AppClassLoader#1830e4a7, see the next exception for details.
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.newEmbedSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.seeNextException(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.bootDatabase(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection.<init>(Unknown Source)
at org.apache.derby.impl.jdbc.EmbedConnection40.<init>(Unknown Source)
at org.apache.derby.jdbc.Driver40.getNewEmbedConnection(Unknown Source)
at org.apache.derby.jdbc.InternalDriver.connect(Unknown Source)
at org.apache.derby.jdbc.Driver20.connect(Unknown Source)
at org.apache.derby.jdbc.AutoloadedDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(DriverManager.java:579)
at java.sql.DriverManager.getConnection(DriverManager.java:243)
at model.DBConnection.<init>(DBConnection.java:31)
at model.DBConnection.<clinit>(DBConnection.java:12)
at test.DBTest.main(DBTest.java:11)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
Caused by: java.sql.SQLException: Failed to start database 'C:/Users/Puk/IdeaProjects/DerbyTest/database/Ablauf' with class loader sun.misc.Launcher$AppClassLoader#1830e4a7, see the next exception for details.
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.wrapArgsForTransportAcrossDRDA(Unknown Source)
... 20 more
Caused by: java.sql.SQLException: Another instance of Derby may have already booted the database C:\Users\Puk\IdeaProjects\DerbyTest\database\Ablauf.
at org.apache.derby.impl.jdbc.SQLExceptionFactory.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.wrapArgsForTransportAcrossDRDA(Unknown Source)
at org.apache.derby.impl.jdbc.SQLExceptionFactory40.getSQLException(Unknown Source)
at org.apache.derby.impl.jdbc.Util.generateCsSQLException(Unknown Source)
... 17 more
Caused by: ERROR XSDB6: Another instance of Derby may have already booted the database C:\Users\Puk\IdeaProjects\DerbyTest\database\Ablauf.
at org.apache.derby.iapi.error.StandardException.newException(Unknown Source)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.privGetJBMSLockOnDB(Unknown Source)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.getJBMSLockOnDB(Unknown Source)
at org.apache.derby.impl.store.raw.data.BaseDataFileFactory.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
at org.apache.derby.impl.store.raw.RawStore.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
at org.apache.derby.impl.store.access.RAMAccessManager.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startModule(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.bootServiceModule(Unknown Source)
at org.apache.derby.impl.db.BasicDatabase.bootStore(Unknown Source)
at org.apache.derby.impl.db.BasicDatabase.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.boot(Unknown Source)
at org.apache.derby.impl.services.monitor.TopService.bootModule(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.bootService(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startProviderService(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.findProviderAndStartService(Unknown Source)
at org.apache.derby.impl.services.monitor.BaseMonitor.startPersistentService(Unknown Source)
at org.apache.derby.iapi.services.monitor.Monitor.startPersistentService(Unknown Source)
... 17 more
Exception in thread "main" java.lang.ExceptionInInitializerError
at test.DBTest.main(DBTest.java:11)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
Caused by: java.lang.NullPointerException
at model.DBConnection.createTables(DBConnection.java:41)
at model.DBConnection.<init>(DBConnection.java:35)
at model.DBConnection.<clinit>(DBConnection.java:12)
... 6 more
Process finished with exit code 1
You cannot boot a db from multiple jvms at the same time. This is explained in the docs Derby Dev Guide
HTH
D