Error Exception In Thread Awt-eventqueue-0 Java.lang.nullpointerexception
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This Site Careers Other all forums Forum: Swing / AWT / SWT Java GUI Error | AWT-EventQueue-0 vishal khanna Greenhorn Posts: 2 posted 2 years ago Source Code : package phela; import java.awt.EventQueue; import javax.swing.JFrame; import javax.swing.JButton; import javax.swing.JLabel; import java.awt.event.ActionListener; import java.awt.event.ActionEvent; public class MyGui { private JFrame http://stackoverflow.com/questions/21228284/exception-in-thread-awt-eventqueue-0-java-lang-nullpointerexception-error frame; private JLabel lblNewLabel; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { MyGui window = new MyGui(); window.frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } https://coderanch.com/t/639652/GUI/java/Java-GUI-Error-AWT-EventQueue /** * Create the application. */ public MyGui() { initialize(); } /** * Initialize the contents of the frame. */ private void initialize() { frame = new JFrame(); frame.setBounds(100, 100, 450, 300); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.getContentPane().setLayout(null); JButton btnNewButton = new JButton("New button"); btnNewButton.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent arg0) { lblNewLabel.setText("Rampuri"); // user Code } }); btnNewButton.setBounds(168, 177, 89, 23); frame.getContentPane().add(btnNewButton); JLabel lblNewLabel = new JLabel("New label"); lblNewLabel.setBounds(184, 132, 46, 14); frame.getContentPane().add(lblNewLabel); } } Error Message : Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at phela.MyGui$2.actionPerformed(MyGui.java:50) at javax.swing.AbstractButton.fireActionPerformed(Unknown Source) at javax.swing.AbstractButton$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.a
6 Years Ago there are no visible error in the syntax https://www.daniweb.com/programming/software-development/threads/253370/exception-in-thread-awt-eventqueue-0-java-lang-nullpointerexception but when i run the application i keep https://www.mathworks.com/matlabcentral/newsreader/view_thread/173077 getting the following error. i have been trying to fix it for hours and simply cant find the problem. the error that appears when running is; Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException error exception at javax.swing.JComboBox.setModel(JComboBox.java:292) at Application.UserManagement.initComponents(UserManagement.java:234) at Application.UserManagement.
Support Support Newsreader MathWorks Search MathWorks.com MathWorks Newsreader Support MATLAB Newsgroup MATLAB Central Community Home MATLAB Answers File Exchange Cody Blogs Newsreader Link Exchange ThingSpeak Anniversary Home Post A New Message Advanced Search Help MATLAB Central Community Home MATLAB Answers File Exchange Cody Blogs Newsreader Link Exchange ThingSpeak Anniversary Home Post A New Message Advanced Search Help Trial software Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap space Subject: Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap space From: Nasser Abbasi Date: 23 Jul, 2008 05:19:50 Message: 1 of 6 Reply to this message Add author to My Watch List View original format Flag as spam 2007a, student version on windoz XP SP2. I use GUIDE, and after sometime of using it, I notice it gets sluggish in its response to editing and I see the following Java errors on the console: "Exception in thread "AWT-EventQueue-0" java.lang.OutOfMemoryError: Java heap space" I am not sure why it runs out of RAM so fast. as I have 4 GB of physical RAM. I did a google on the above and I see that others have seen this. I wonder if there is any update on this problem that someone from Mathworks or others can comment on. Is this still a problem in later Matlab releases? thanks, Nasser Subject: Exception in thread From: Stefan Stefan (view profile) 15 posts Date: 30 Jul, 2008 08:34:03 Message: 2 of 6 Reply to this message Add author to My Watch List View original format Flag as spam Dear Nasser, I'm dealing with the same problems. And it seems, that noone really knows something about the java heap memory. I never got a clear response on this topic. I found a small workaround to free some heap memory. heapTotalMemory = java.lang.Runtime.getRuntime.totalMemory; heapFreeMemory = java.lang.Runtime.getRuntime.freeMemory; if(heapFreeMemory < (heapTotalMemory*0.01)) java.lang.Runtime.getRuntime.gc; end I'm calling the java garbace collector if the free memory drops below a certain limit. Maybe this helps. Keep me up to date if you get any news according to the java heap memory. Best regards,