So this is my first time posting, please be gentle :3
General overview:
My goal is to be able to give my program a XSD file, then the program generates a bean, generates a nice GUI using reflection on the bean, then I can enter appropriate values into the textfields and then the program updates the bean with the values and finally marshalls the bean into a nice XML.
It's coming along pretty good, but yesterday I stumbled over an error that I can't figure out..
StackTrace
java.lang.ClassNotFoundException: X.Y.Z.BEAN_FILE_WITHOUT_.JAVA
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at X.Y.Z.GenerateXMLService.generateBean(GenerateXMLService.java:101)
at X.Y.Z.view.Gui$1.handle(Gui.java:56)
at X.Y.Z.view.Gui$1.handle(Gui.java:1)
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.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.BehaviorSkinBase$1.handle(Unknown Source)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(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.access$1800(Unknown Source)
at javafx.scene.Scene.impl_processMouseEvent(Unknown Source)
at javafx.scene.Scene$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$300(Unknown Source)
at com.sun.glass.ui.win.WinApplication$4$1.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
generateBean
public Class generateBean(File xsd) {
String finalDir = System.getProperty("user.dir") + "/src/main/java";
String xsdDir = xsd.getParentFile().getAbsolutePath();
try {
Process p = Runtime.getRuntime().exec(
"cmd /c cd " + xsdDir + " && xjc -d " + finalDir
+ " -p PACKAGE_PATH_GOES_HERE " + xsd.getName().toString());
p.waitFor();
} catch (IOException | InterruptedException e) {
Gui.errorPopUp(e);
}
/**
* Get the newly created files and put them in an array
*/
File[] fList = new File[2];
fList = new File("DIRECTORY_PATH_GOES_HERE").listFiles();
/**
* Get the file that isn't Objectfactory.java ---> that's the bean
*/
for (File file : fList) {
if (!"ObjectFactory.java".equals(file.getName())) {
String beanName = file.getName();
String beanBinaryName = "PACKAGE_PATH_GOES_HERE"
+ beanName.substring(0, beanName.length() - 5);
Class beanClass = null;
try {
beanClass = Class.forName(beanBinaryName); //this is line 101
return beanClass;
} catch (ClassNotFoundException e) {
Gui.errorPopUp(e);
}
}
}
return null;
}
So I checked first if the beanBinaryName is correct, and I think it is. It has the following format:
com.foo.foo.some.more.foo.beanbag.bean
Then I started googling with the error message and stumbled accross this post:
Link to the blog
But to be honest I didn't really understand what he was trying to explain. The stacktrace looks similar, but I just started with java a few months ago and still consider myself a newbie. Do you have any advice what the error might be? Thank in advance!
EDIT / SOLUTION:
My first mistake was trying to use class.forName() on a .java file. This only works with compiled files, e.g. .class.
After I fixed that i was still getting error messages, but after playing around with the URLClassLoader it worked :D I renamed and refactored this method compared to the method at the top, so in this one we really only get the class, while in my first example I also generate the .java files. I now do this in a seperate method to keep things organized.
public Class getClassFromBean() {
File[] fList = new File[3];
fList = new File("foo/beanbag").listFiles();
Class beanClass = null;
for (File file : fList) {
String lastSix = file.getName().toString().substring(file.getName().length() - 6);
if (".class".equals(lastSix)) {
String beanBinaryName = "foo.beanbag."
+ file.getName().toString().substring(0, file.getName().toString().length() - 6);
try {
File root = new File(System.getProperty("user.dir") + "/src/main/java");
URLClassLoader classLoader = URLClassLoader.newInstance(new URL[] { root.toURI()
.toURL() });
beanClass = Class.forName(beanBinaryName, true, classLoader);
} catch (ClassNotFoundException | MalformedURLException e) {
Gui.errorPopUp(e);
}
return beanClass;
}
}
return beanClass;
}
Method Class.forName() works only for compiled classes i.e. for files with extension '.class'. You cannot just put '.java' file to your classpath.
Related
I'm using clear() method for removing data from chart.
#FXML
public void restartButtonClicked() {
System.out.println("Restarting...");
timeLine.getKeyFrames().clear();
axesTest.getData().clear();
}
In this function, but once button get clicked - it works.. but second time while I am gonna click it, it throw exception :
Exception in thread "JavaFX Application Thread" java.lang.IllegalArgumentException: Duplicate series added
at javafx.scene.chart.XYChart.lambda$new$550(Unknown Source)
at com.sun.javafx.collections.ListListenerHelper$SingleChange.fireValueChangedEvent(Unknown Source)
at com.sun.javafx.collections.ListListenerHelper.fireValueChangedEvent(Unknown Source)
at javafx.collections.ObservableListBase.fireChange(Unknown Source)
at javafx.collections.ListChangeBuilder.commit(Unknown Source)
at javafx.collections.ListChangeBuilder.endChange(Unknown Source)
at javafx.collections.ObservableListBase.endChange(Unknown Source)
at javafx.collections.ModifiableObservableListBase.addAll(Unknown Source)
at sample.Controller.startButtonClicked(Controller.java:138)
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)
at javafx.fxml.FXMLLoader$MethodHandler.invoke(Unknown Source)
at javafx.fxml.FXMLLoader$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.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.BehaviorSkinBase$1.handle(Unknown Source)
at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(Unknown Source)
at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(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.access$1500(Unknown Source)
at javafx.scene.Scene.impl_processMouseEvent(Unknown Source)
at javafx.scene.Scene$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.lambda$handleMouseEvent$354(Unknown Source)
at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(Unknown Source)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(Unknown Source)
at com.sun.glass.ui.View.handleMouseEvent(Unknown Source)
at com.sun.glass.ui.View.notifyMouse(Unknown Source)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.lambda$null$148(Unknown Source)
at java.lang.Thread.run(Unknown Source)
So the problem is in 138 line as well as in 159 line of code from method :
#SuppressWarnings("unchecked")
#FXML
public void startButtonClicked(ActionEvent event) {
if (comboBox.getValue() == null) {
System.out.print("Nie wybrano opcji.");
} else {
if(comboBox.getValue().equals("Gaussian Wave : non-Dispersive")) {
System.out.println("Gaussian Wave : non-Dispersive");
axesTest.setTitle("Gaussian Wave : non-Dispersive");
series.setName("bla");
series1.setName("ssad");
series2.setName("asf");
seriesList.add(series);
seriesList.add(series1);
seriesList.add(series2);
timeLine = new Timeline();
gaussianWave = new GaussianWave( seriesList, axes, timeLine );
seriesList = gaussianWave.draw();
gaussianWave.update(axesTest);
axesTest.getData().retainAll();
axesTest.getData().addAll(seriesList);
} else if(comboBox.getValue().equals("Gaussian Wave : Dispersive")) {
System.out.println("Gaussian Wave : Dispersive");
axesTest.setTitle("Gaussian Wave : Dispersive");
series.setName("bla");
series1.setName("ssad");
series2.setName("asf");
seriesList.add(series);
seriesList.add(series1);
seriesList.add(series2);
timeLine = new Timeline();
gaussianWaveDispersive = new GaussianWaveDispersive( seriesList, axes, timeLine );
seriesList = gaussianWaveDispersive.draw();
gaussianWaveDispersive.update(axesTest);
axesTest.getData().retainAll();
axesTest.getData().addAll(seriesList);
}
}
}
and the problem is in :
axesTest.getData().addAll(seriesList);
Why do I get this exception after clearing all of data from the chart ? How could I fix this?
You clear the ObservableList stored in the dataProperty of the Series:
axesTest.getData().clear();
but you use an intermediate list(?) called seriesList, rather than adding Data directly:
seriesList.add(series);
seriesList.add(series1);
seriesList.add(series2)
...
axesTest.getData().addAll(seriesList);
The problem is you don't clear seriesList before adding the elements, so it contains the elements on the second click twice, which will result in an IllegalArgumentException.
Actually I don't know what happens here:
gaussianWave = new GaussianWave( seriesList, axes, timeLine );
seriesList = gaussianWave.draw();
but it seems that seriesList contains the previous Data objects after these lines.
I get the following error, when puting an element in the ehcache. Does anyone have any idea why this error occures?
Thank you in advance.
This is put method:
#SuppressWarnings("unchecked")
#Override
public void putActivity(Activity activity) {
// put activity itself
Serializable activityKey = KEY_PREFIX_ACTIVITY + activity.getId();
final Element activityElement = new Element(activityKey, activity);
getCache().put(activityElement);
// add activity to the list of user
ArrayList<Activity> activities = null;
Serializable userKey = KEY_PREFIX_USER_ACTIVITIES + activity.getExecutingUserId();
Element userActivities = getCache().get(userKey);
if (userActivities == null) {
activities = new ArrayList<Activity>();
userActivities = new Element(userKey, activities);
} else {
activities = (ArrayList<Activity>) userActivities.getObjectValue();
}
activities.add(activity);
getCache().put(userActivities);
}
and here is the corresponding erorr:
Mrz 05, 2016 11:07:40 AM net.sf.ehcache.store.disk.DiskStorageFactory$DiskWriteTask call
Schwerwiegend: Disk Write of u-1 failed:
net.sf.ehcache.CacheException: Failed to serialize element due to ConcurrentModificationException. This is frequently the result of inappropriately sharing thread unsafe object (eg. ArrayList, HashMap, etc) between threads
at net.sf.ehcache.store.disk.DiskStorageFactory.serializeElement(DiskStorageFactory.java:405)
at net.sf.ehcache.store.disk.DiskStorageFactory.write(DiskStorageFactory.java:385)
at net.sf.ehcache.store.disk.DiskStorageFactory$DiskWriteTask.call(DiskStorageFactory.java:477)
at net.sf.ehcache.store.disk.DiskStorageFactory$PersistentDiskWriteTask.call(DiskStorageFactory.java:1071)
at net.sf.ehcache.store.disk.DiskStorageFactory$PersistentDiskWriteTask.call(DiskStorageFactory.java:1055)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(Unknown Source)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: java.util.ConcurrentModificationException
at java.util.ArrayList.writeObject(Unknown Source)
at sun.reflect.GeneratedMethodAccessor33.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.defaultWriteObject(Unknown Source)
at net.sf.ehcache.Element.writeObject(Element.java:875)
at sun.reflect.GeneratedMethodAccessor31.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.writeObject(Unknown Source)
at net.sf.ehcache.util.MemoryEfficientByteArrayOutputStream.serialize(MemoryEfficientByteArrayOutputStream.java:97)
at net.sf.ehcache.store.disk.DiskStorageFactory.serializeElement(DiskStorageFactory.java:403)
... 10 more
and here more details from ehcache source code:
private MemoryEfficientByteArrayOutputStream [More ...] serializeElement(Element element) throws IOException {
// A ConcurrentModificationException can occur because Java's serialization
// mechanism is not threadsafe and POJOs are seldom implemented in a threadsafe way.
// e.g. we are serializing an ArrayList field while another thread somewhere in the application is appending to it.
try {
return MemoryEfficientByteArrayOutputStream.serialize(element);
} catch (ConcurrentModificationException e) {
throw new CacheException("Failed to serialize element due to ConcurrentModificationException. " +
"This is frequently the result of inappropriately sharing thread unsafe object " +
"(eg. ArrayList, HashMap, etc) between threads", e);
}
}
You are updating an object while it's been serialized (ehcache try to save it to disk). You should store in a cache only an immutable object.
In your case, don't try to reuse the ArrayList, create a new one:
if (userActivities == null) {
activities = new ArrayList<Activity>();
userActivities = new Element(userKey, activities);
} else {
activities = new ArrayList<Activity>((List) userActivities.getObjectValue());
}
Instead of an ArrayList, you can instanciate a CopyOnWriteArrayList.
Hello all I am experiencing issues with my JOptionPane.showInputDialog input field.
The issue i am experiencing that is when the cancel button is selected or the OK button is selected with empty or with categorical i am greeted with an error. Any suggestions.
My first attempt at fixing this i changed the c int into an interger therefore i could use an if statement along with null such as
Integer cInterger = new Integer(c);
if (cInterger.equals(null)){
return;}
Along with
cInterger == null
cInterger !=null
But to no avail
int a = 0; //
int b = 0; //
int c = 0; //
if (selected) {
if (command.equals("amount")) {
Scanner readFile = null;
try {
readFile = new Scanner(new FileReader("BANK.txt"));
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String account = "";
account = readFile.nextLine();
String amount = JOptionPane.showInputDialog(frame,"Enter an amount"); //assign user input to string amount
a= Integer.parseInt(account); //conversion of scanned string to int for easy subtraction
b= Integer.parseInt(amount);
c = a-b;
try {
if( c == 0){
JOptionPane.showMessageDialog(null,"Granted.","Granted",JOptionPane.WARNING_MESSAGE);}
else if (c > 0){
JOptionPane.showMessageDialog(null,"Granted.","Granted",JOptionPane.INFORMATION_MESSAGE); }
else{
JOptionPane.showMessageDialog(null,"Denied.","Denied",JOptionPane.ERROR_MESSAGE);}
Resulting errors
Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: null
at java.lang.NumberFormatException.forInputString(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at java.lang.Integer.parseInt(Unknown Source)
at Options$1MyItemListener.itemStateChanged(Options.java:58)
at javax.swing.AbstractButton.fireItemStateChanged(Unknown Source)
at javax.swing.AbstractButton$Handler.itemStateChanged(Unknown Source)
at javax.swing.DefaultButtonModel.fireItemStateChanged(Unknown Source)
at javax.swing.JToggleButton$ToggleButtonModel.setSelected(Unknown Source)
at javax.swing.ButtonGroup.setSelected(Unknown Source)
at javax.swing.JToggleButton$ToggleButtonModel.setSelected(Unknown Source)
at javax.swing.JToggleButton$ToggleButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.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$400(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)
If you take a look at the JavaDocs, you will find that
Returns: user's input, or null meaning the user canceled the input
So attempting to parse null makes no sense, instead you should be using something like...
if (amount != null) {
a = Integer.parseInt(amount);
//...
Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: For input string: "" seems reasonably obvious.
if (amount != null) {
if (amount.trim().length() > 0) {
//...
} else {
JOptionPane.showMessageDialog(frame, "The amount you entered is invalid");
}
You should also check the account value as well
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Closed 9 years ago.
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I have this code, which creates a textfield and a button to let the user search for data in an array:
//Creates a form to search data, list for it and buttons to sort the list.
rightPanel.add(Box.createRigidArea(new Dimension(20, 20)));
final TextField searchTextField;
searchTextField = new TextField ();
rightPanel.add(searchTextField);
rightPanel.add(Box.createRigidArea(new Dimension(20, 20)));
JButton searchConfirmButton = new JButton("Search");
rightPanel.add(searchConfirmButton);
searchConfirmButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e)
{
try {
search = searchTextField.getText();
int index = Arrays.asList(data).indexOf(search);
for (String result : data) {
if (result.contains(search)) {
System.out.println(result);
System.out.println(index);
}
}
} catch (NullPointerException e1) {
}
}
});
But whenever I search for the data, whether it exists or not, the program returns me an nullpointerexception with the following content:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at program.Program$4$1.actionPerformed(Program.java:233)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$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.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)
In this case, row 233 contains this line if (result.contains(search)) {
data looks like an array type that can hold data values or null pointers. You should try:
System.out.println("Found index: " + index);
for (String result : data) {
if (result != null && result.contains(search)) {
System.out.println("Found result: " + result);
}
//If you are still confused than the right else here will help.
}
If, for example, you split a string with two spaces in a row by space, then depending on your function parameters to split(), you can end up with an empty string in that location and you need to skip it effectively.
This is the method called when the player has to be removed from the game. Both these methods are in different classes.
GameboardGUI class
Vector<Player> players = new Vector<Player>();
public void removePlayerFromGame(Player playerToRemove)
{
//go through the playerToRemove's properties and reset all their variables
for(int i = 0; i < playerToRemove.getPropertiesOwned().size(); i++)
{
//code to reset the player's properties to an unowned/unmodified state
}
//same with transports
for(int i = 0; i < playerToRemove.getTransportsOwned().size(); i++)
{
//code to reset the player's transports to an unowned/unmodified state
}
//just updating the vector based on the playerToRemove's position
if(players.get(0) == playerToRemove)
{
players.remove(playerToRemove);
updatePlayerInformation();
}
else
{
players.remove(playerToRemove);
updatePlayerVector(players);
updatePlayerInformation();
}
}
This is how the method is called:
If the current player (fromMe) lands on a property and cant afford to pay the rent (i.e. their balance reaches 0 as a result of takefrombalance(1200);, currently hardcoded to 1200 to make testing easier) they are removed in the if statement if(fromMe.isBankrupt())
Property Class
GameboardGUI gui = new GameboardGUI();
public void payRent(Player fromMe, Player toYou, int rent)
{
//remove rent from the current player
fromMe.takeFromBalance(1200);
//add it to the owner
toYou.addToBalance(rent);
GameboardGUI.addGameFeedMessage(fromMe.getName() + " has paid " + rent + " in rent to " + toYou.getName());
GameboardGUI.addGameFeedMessage(toYou.getName() + "'s balance is now " + toYou.getBalance());
if(fromMe.isBankrupt())
{
//THIS IS THE CALL THAT THROWS THE NullPointerException
gui.removePlayerFromGame(fromMe);
}
else
{
GameboardGUI.addGameFeedMessage(fromMe.getName() + "'s balance is now " + fromMe.getBalance());
}
}
Here is the stack trace when the line is reached:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at PropertyTile.payRent(PropertyTile.java:254)
at PropertyTile.landedOnProperty(PropertyTile.java:239)
at GameboardGUI.playerHasLanded(GameboardGUI.java:1905)
at Player.setPosition(Player.java:82)
at Player.movePlayer(Player.java:101)
at GameboardGUI$11.actionPerformed(GameboardGUI.java:1536)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$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.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$000(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)
It's really hard to help you without a stacktrace and the line numbers for your code, but we're trying.
If that's really the line (and not actually within removePlayerFromGame), the member gui hasn't been initialized.
Of course, if it's not that line, it could simply be that playerToRemove is null, and the NullPointerException is actually happening a couple of lines above.
Or, another possibility is that it's happening within removePlayerFromGame, in which case the most likely case is that playerToRemove hasn't been properly set up - that its getPropertiesOwned() or getTransportsOwned() methods are returning null.
I would add the following two lines, as a first step to see what happens:
if(fromMe==null)
System.out.println("from me is null");
if(gui == null)
System.out.println("gui is null");
gui.removePlayerFromGame(fromMe);
One of the two object references is null causing the exception.
Otherwise, the method removePlayerFromGame is doing something, but I don't think that would be the case because the stacktrace would include additional methods.
You say in the code that the Exception is thrown when you reach the line
gui.removePlayerFromGame(fromMe);
However, the top of stacktrace you are showing is Player.movePlayer(), with its bottom at PropertyTile.payRent().
Is this payRent() receiving any parameter? Can you post it source?