LostFocus problem

Hi all, i'm having a problem with the lostFocus
Event.
I java JTextField that on its onlostFocus event calls
a webservice, and it displays the result with
JOptionPane.showMessageDialog.
and the lostFocus event executes again and again when
the ok button is pressed on the dialog.
thank a lotWhaddayamean thank(ed) a lot ... we didn't do it! Seriously, without 'seeing' the code, I'd say you need a requestFocus() method call on that JTextArea.

Similar Messages

Problem with Listeners/ requestFocus()

Hello,
I am new to Java (started learning two months back), There is a problem with the requestFocus() in the focusListener. The program does not return the focus to the object indicated in the requestFocus but it shows multiple cusors!!
The faculity at the institute where I am learning could not rectify the error.
Is the error because of the myMethod() which I am using. I had made this method to prove to my professor that we can reduce the code drastically while using the gridbaglayout.
The code which I had written is as under:
// file name ShopperApplet.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ShopperApplet extends JApplet implements ActionListener, FocusListener,Runnable
     //static JPanel sP;
     //static JPanel oP;
     JTabbedPane tabbedPane = new JTabbedPane();
     JPanel sP;
     JPanel oP;
     JPanel pwd = new JPanel();
     // Layout Decleration of oP
     GridBagLayout ordL = new GridBagLayout();
     GridBagConstraints ordC = new GridBagConstraints();
     // Layout Decleration of sP
     FlowLayout flow = new FlowLayout();
     // Variables of sP
          JTextField textShopperId;
          JPasswordField textPassword;
          JTextField textFirstName ;
          JTextField textLastName ;
          JTextField textEmailId ;
          JTextField textAddress ;
          JComboBox comboCity ;
          JTextField textState ;
          JTextField textCountryId ;
          JTextField textZipCode ;
          JTextField textPhone ;
          JTextField textCreditCardNo ;
          JRadioButton rbVisa;
          JRadioButton rbMaster;
          JRadioButton rbAmEx;
          ButtonGroup BGccType;
          //JComboBox comboCreditCardType;
          //JTextField textExperyDate;
          JComboBox cmbDt;
          JComboBox cmbMth;
          JComboBox cmbYear;
          JButton btnSubmit;
          JButton btnReset;
     // Variables of oP
          // Variable Decleration od oP
          JTextField txtOrderNo;
          JTextField txtToyId;
          JTextField txtQty;
          JRadioButton rbYes;
          JRadioButton rbNo;
          ButtonGroup bgGiftWrap;
          JComboBox cmbWrapperId;
          JTextField txtMsg;
          JTextField txtToyCost;
          JButton btnOSubmit;
          JButton btnOReset;
     // Variables of pwd
          JTextField txtShopperId;
          JPasswordField txtPassword;
          JButton btnPSubmit;
          JButton btnPReset;
          JButton btnPNew;
          JButton btnPLogoff;
          JLabel lblN, lblN1;
          Thread t,t1;
     Font TNR = new Font("Times New Roman",1,15);
     Font arial = new Font("Arial",2,15);
     public void sPDet()
          //Variable Decleration of sP
          textShopperId = new JTextField(6);
          textPassword = new JPasswordField(4);
          textPassword.addFocusListener(this);
          //textPassword = new JTextField(4);
          textPassword.setEchoChar('*');
          textFirstName = new JTextField(20);
          textLastName = new JTextField(20);
          textEmailId = new JTextField(25);
          textAddress = new JTextField(20);
          String cityList[] = {"New Delhi", "Mumbai", "Calcutta", "Hyderabad"};
          comboCity = new JComboBox(cityList);
          comboCity.setEditable(true);
          textState = new JTextField(30);
          textCountryId = new JTextField(25);
          textZipCode = new JTextField(6);
          textPhone = new JTextField(25);
          textCreditCardNo = new JTextField(25);
          String cardTypes[] = {"Visa", "Master Card", "American Express"};
          //comboCreditCardType = new JComboBox(cardTypes);
          rbVisa = new JRadioButton("Visa");
          rbMaster = new JRadioButton("Master Card");
          rbAmEx = new JRadioButton("American Express");
          BGccType = new ButtonGroup();
          BGccType.add(rbVisa);
          BGccType.add(rbMaster);
          BGccType.add(rbAmEx);
          String stDt[] = {"1","2","3","4","5","6","7","8","9","10","11","12","13","14","15","16","17","18","19","20","21","22","23","24","25","26","27","28","29","30","31"};
          String stMth[] = {"January","February","March","April","May","June","July","August","September","October","November","December"};
          String stYear[] = {"2001","2002","2003","2004","2005","2006","2007","2008","2009","2010"};
          cmbDt = new JComboBox(stDt);
          cmbMth = new JComboBox(stMth);
          cmbYear = new JComboBox(stYear);
          //textExperyDate = new JTextField(10);
          btnSubmit = new JButton("Submit");
          btnReset = new JButton("Reset");
          // Adding Layout Controls
          sP.setLayout(ordL);
          sP.setBackground(Color.green);
          myLayout(textShopperId,3,1,sP,"FM","Shopper Id");
          myLayout(textPassword,3,2,sP,"FM","Password");
          myLayout(textFirstName,3,3,sP,"FM","First Name") ;
          myLayout(textLastName,3,4,sP,"FM","Last Name") ;
          myLayout(textEmailId,3,5,sP,"FM","E-Mail Id") ;
          myLayout(textAddress,3,6,sP,"FM", "Address") ;
          myLayout(comboCity,3,7,sP,"FM","City") ;
          myLayout(textState,3,8,sP,"FM","State") ;
          myLayout(textCountryId,3,9,sP,"FM","Country") ;
          myLayout(textZipCode,3,10,sP,"FM","Zip Code") ;
          myLayout(textPhone,3,11,sP,"FM","Phone") ;
          myLayout(textCreditCardNo,3,12,sP,"FM","Credit Card No.") ;
          //myLayout(rbVisa,3,13,sP);
          JPanel newPanel = new JPanel();
          newPanel.add(rbVisa);
          newPanel.add(rbMaster);
          newPanel.add(rbAmEx);
          myLayout(newPanel,3,13,sP,"FM","Credit Card Type");
          //myLayout(rbMaster,4,13);
          //myLayout(rbAmEx,5,13);
          JPanel newPanel1 = new JPanel();
          newPanel1.add(cmbDt);
          newPanel1.add(cmbMth);
          newPanel1.add(cmbYear);
          myLayout(newPanel1,3,14,sP,"FM","Expiry Date");
          //myLayout(textExperyDate,3,14,sP,"FM");
          myLayout(btnSubmit,1,17,sP,"AL","Submit");
          myLayout(btnReset,3,17,sP,"AL","Reset");
     public void oPDet()
          txtOrderNo = new JTextField(10);
          txtToyId = new JTextField(10);
          txtQty = new JTextField(10);
          rbYes = new JRadioButton("Yes");
          rbNo = new JRadioButton("No");
          bgGiftWrap = new ButtonGroup();
          bgGiftWrap.add(rbYes);
          bgGiftWrap.add(rbNo);
          String wrapperTypes[] = {"Blue Stripes", "Red Checks", "Green Crosses","Yellow Circles", "Red & Purple Stripes"};
          cmbWrapperId = new JComboBox(wrapperTypes);
          txtMsg = new JTextField(10);
          txtToyCost = new JTextField(10);
          btnOSubmit = new JButton("Submit");
          btnOReset = new JButton("Reset");
          // Adding Controls to oP
          oP.setLayout(ordL);
          oP.setBackground(Color.yellow);
          myLayout(txtOrderNo,3,1,oP,"FM","Order No.");
          myLayout(txtToyId,3,2,oP,"FM","Toy Id");
          myLayout(txtQty,3,3,oP,"FM","Quantity");
          myLayout(rbYes,3,4,oP,"M");
          myLayout(rbNo,4,4,oP,"M");
          myLayout(cmbWrapperId,3,5,oP,"M","Wrapper Id");
          myLayout(txtMsg,3,6,oP,"FM","Message");
          myLayout(txtToyCost,3,7,oP,"FM","Toy Cost");
          myLayout(btnOSubmit,1,8,oP,"AL","Submit");
          myLayout(btnOReset,3,8,oP,"AL","Reset");
     public void pwdDet()
          pwd.setLayout(ordL);
          pwd.setBackground(Color.green);
          t = new Thread(this);
          t.start();
          t1 = new Thread(this);
          t1.start();
          lblN = new JLabel("");
          lblN1 = new JLabel("");
          txtShopperId = new JTextField(10);
          txtPassword = new JPasswordField(10);
          btnPSubmit = new JButton("Submit") ;
          btnPReset = new JButton("Reset");
          btnPNew = new JButton("New Member");
          btnPLogoff = new JButton("Log Off");
          pwd.setLayout(ordL);
          pwd.setBackground(Color.yellow);
          myLayout(lblN,3,7,pwd);
          myLayout(lblN1,3,8,pwd);
          myLayout(txtShopperId,3,1,pwd,"FM","Shopper Id.");
          myLayout(txtPassword,3,2,pwd,"FM","Password");
          myLayout(btnPSubmit,2,4,pwd,"AL","Submit");
          myLayout(btnPReset,3,4,pwd,"AL","Reset");
          myLayout(btnPNew,2,5,pwd,"AL","New");
          myLayout(btnPLogoff,3,5,pwd,"AL","Log Off");
     public void run()
          int ctr =0;
          String ili[] = {"India","is","a","Great","Country"};
          int ctr1 = 0;
          String iib[] = {"India","is","the","Best"};
          Thread myThread = Thread.currentThread();
          if (myThread == t)
               while (t != null)
                    lblN.setText(ili[ctr]);
                    ctr++;
                    if (ctr >=5) ctr=0;
                    try
                         t.sleep(500);
                    catch(InterruptedException e)
                         showStatus("India is a great Country has been interrupter");
          else
               while (t1 != null)
                    lblN1.setText(iib[ctr1]);
                    ctr1++;
                    if (ctr1 >=4) ctr1=0;
                    try
                         t1.sleep(1000);
                    catch(InterruptedException e)
                         showStatus("India is the best has been interrupter");
     public void myLayout(JComponent aObj, int x, int y, JPanel aPanel,String aListener,String toolTip)
          ordC.anchor=GridBagConstraints.NORTHWEST;
          JLabel aLabel = new JLabel(toolTip);
          ordC.gridx = x-1;
          ordC.gridy = y;
          ordL.setConstraints(aLabel,ordC);
          aPanel.add(aLabel);
          aObj.setToolTipText("Enter "+toolTip+" here");
          aObj.setForeground(Color.red);
          aObj.setBackground(Color.green);
          if (aListener.indexOf("F")     != -1)
               aObj.addFocusListener(this);
          //if (aListener.indexOf("M")     != -1)
               //aObj.addMouseListener(this);
          aObj.setFont(TNR);
          ordC.gridx = x;
          ordC.gridy = y;
          ordL.setConstraints(aObj,ordC);
          aPanel.add(aObj);
     public void myLayout(JComponent aObj, int x, int y, JPanel aPanel,String aListener)
          ordC.anchor=GridBagConstraints.NORTHWEST;
          aObj.setForeground(Color.red);
          aObj.setBackground(Color.green);
          if (aListener.indexOf("F")     != -1)
               aObj.addFocusListener(this);
          //if (aListener.indexOf("M")     != -1)
               //aObj.addMouseListener(this);
          aObj.setFont(TNR);
          ordC.gridx = x;
          ordC.gridy = y;
          ordL.setConstraints(aObj,ordC);
          aPanel.add(aObj);
     public void myLayout(JButton aObj, int x, int y, JPanel aPanel,String aListener, String toolTip)
          aObj.setToolTipText(toolTip);
          ordC.anchor=GridBagConstraints.NORTHWEST;
          aObj.setForeground(Color.red);
          if (aListener.indexOf("F")     != -1)
               aObj.addFocusListener(this);
          //if (aListener.indexOf("M")     != -1)
               //aObj.addMouseListener(this);
          if (aListener.indexOf("A")     != -1)
               aObj.addActionListener(this);
          aObj.setFont(TNR);
          ordC.gridx = x;
          ordC.gridy = y;
          ordL.setConstraints(aObj,ordC);
          aPanel.add(aObj);
     public void myLayout(JTextField aObj, int x, int y, JPanel aPanel,String aListener,String toolTip)
          ordC.anchor=GridBagConstraints.NORTHWEST;
          //aObj = new JTextField(10);
          JLabel aLabel = new JLabel(toolTip);
          ordC.gridx = x-1;
          ordC.gridy = y;
          ordL.setConstraints(aLabel,ordC);
          aPanel.add(aLabel);
          aObj.setToolTipText("Enter "+toolTip+" here");
          aObj.setForeground(Color.red);
          if (aListener.indexOf("F")     != -1)
               aObj.addFocusListener(this);
          //if (aListener.indexOf("M")     != -1)
          //     aObj.addMouseListener(this);
          if (aListener.indexOf("A")     != -1)
               aObj.addActionListener(this);
          aObj.setFont(TNR);
          ordC.gridx = x;
          ordC.gridy = y;
          ordL.setConstraints(aObj,ordC);
          aPanel.add(aObj);
     public void myLayout(JLabel aObj, int x, int y, JPanel aPanel)
          ordC.anchor=GridBagConstraints.SOUTH;
          aObj.setForeground(Color.blue);
          aObj.setFont(TNR);
          ordC.gridx = x;
          ordC.gridy = y;
          ordL.setConstraints(aObj,ordC);
          aPanel.add(aObj);
     public void init()
          getContentPane().add(tabbedPane);
          sP = new JPanel();
          sPDet();
          oP = new JPanel();
          oPDet();
          pwdDet();
          tabbedPane.addTab("Login",null,pwd,"Login");
          tabbedPane.addTab("Shopper",null,sP,"Shopper Details");
          tabbedPane.addTab("Order",null,oP,"Order Details");
          tabbedPane.setEnabledAt(2, false);
          tabbedPane.setEnabledAt(1, false);
     public void actionPerformed(ActionEvent e)
          Object obj = e.getSource();
          if (obj == btnSubmit)
               if (validShopperId() == false) return;
               if (validPassword() == false) return;
               if (validFirstName() == false) return ;
               if (validLastName() == false) return ;
               if (validEmailId() == false) return;
               if (validAddress() == false) return;
               if (validState() == false) return;
               if (validCountryId() == false) return;
               if (validZipCode() == false) return;
               if (validCreditCardNo() == false) return ;
               resetShopper();
               tabbedPane.setEnabledAt(1,false);
               tabbedPane.setEnabledAt(2,false);
               tabbedPane.setSelectedIndex(0);
               // also can be written as tabbedPane.setSelectedComponent(pwd);
               //tabbedPane.remove(sP);
          if (obj == btnReset)
               resetShopper();
               tabbedPane.setEnabledAt(2,false);
               //textExperyDate.setText("");
          if (obj == btnOSubmit)
               if (validOrderNo() == false) return;
               if (validToyId() == false) return;
               if (chkNullEntry(txtQty, "Quantity")) return ;
               if (chkNullEntry(txtToyCost, "Toy Cost")) return ;
          if (obj == btnOReset)
               resetOrder();
          if (obj == btnPSubmit)
               if (validPShopperId() && validPPassword())
                    tabbedPane.setEnabledAt(2, true);
                    tabbedPane.setEnabledAt(1, false);
                    txtShopperId.setText("");
                    txtPassword.setText("");
                    resetPassword();
                    //tabbedPane.addTab("Order",null,oP,"Order Details");
          if (obj == btnPReset)
               resetPassword();
               tabbedPane.setEnabledAt(1, false);
               tabbedPane.setEnabledAt(2, false);
          if (obj == btnPNew)
               tabbedPane.setEnabledAt(1, true);
               tabbedPane.setEnabledAt(2, false);
               resetPassword();
               tabbedPane.setSelectedComponent(sP);
               //tabbedPane.addTab("Shopper",null,sP,"Shopper Details");
          if (obj == btnPLogoff)
               tabbedPane.setEnabledAt(2, false);
               tabbedPane.setEnabledAt(1, false);
               resetPassword();
     public void focusGained(FocusEvent fe)
          //Object aObj = fe.getSource();
          //showStatus("Current Object is "+aObj);
     public void resetPassword()
          txtShopperId.setText("");
          txtPassword.setText("");
     public void resetShopper()
               textShopperId.setText("");
               textPassword.setText("");
               textFirstName.setText("") ;
               textLastName.setText("") ;
               textEmailId.setText("") ;
               textAddress.setText("") ;
               textState.setText("") ;
               textCountryId.setText("") ;
               textZipCode.setText("") ;
               textPhone.setText("") ;
               textCreditCardNo.setText("") ;
     public void resetOrder()
          txtOrderNo.setText("");
          txtToyId.setText("");
          txtQty.setText("") ;
          txtToyCost.setText("") ;
          txtMsg.setText("") ;
     public void focusLost(FocusEvent fe)
          try{
               Object obj = fe.getSource();
               if (obj == textShopperId &&     validShopperId() == false)
                    //textShopperId.requestFocus();
                    return;
               if (obj == textPassword && validPassword() == false)
                    //textPassword.requestFocus();
                    return;
               if (obj == textFirstName && validFirstName() == false)
                    //textFirstName.requestFocus();
                    return;
               if (obj == textEmailId && validEmailId() == false)
                    //textEmailId.requestFocus();
                    return;
               if (obj == txtOrderNo && validOrderNo() == false)
                    //txtOrderNo.requestFocus();
                    return;
               if (obj == txtToyId && validToyId() == false);
                    //txtToyId.requestFocus();
                    return;
          catch(Exception e)
               showStatus("error in LostFocus() Method");
     public boolean validShopperId()
          if (chkNullEntry(textShopperId,"Shopper Id")) return false;
          return true;
     public boolean validPassword()
          if (chkNullEntry(textPassword,"Password")) return false;
          return true;
     public boolean validFirstName()
          if (chkNullEntry(textFirstName,"First Name")) return false;
          return true;
     public boolean validLastName()
          if (chkNullEntry(textLastName,"Last Name")) return false;
          return true;
     public boolean validAddress()
          if (chkNullEntry(textAddress,"Address")) return false;
          return true;
     public boolean validState()
          if (chkNullEntry(textState,"State")) return false;
          return true;
     public boolean validCountryId()
          if (chkNullEntry(textCountryId,"Country")) return false;
          return true;
     public boolean validZipCode()
          if (chkNullEntry(textZipCode,"Postal Code")) return false;
          return true;
     public boolean validCreditCardNo()
          if (chkNullEntry(textCreditCardNo,"Credit Card No.")) return false;
          return true;
     public boolean validEmailId()
          if (chkNullEntry(textEmailId,"Email Address")) return false;
          String s1 = textEmailId.getText();
          int abc = s1.indexOf("@");
          if (abc == -1 || abc == 0 || abc == (s1.length()-1))
               JOptionPane.showMessageDialog(sP,"Invalid Email Address","Error Message",JOptionPane.ERROR_MESSAGE);
               //textEmailId.requestFocus();
               return false;
          return true;
     public boolean validOrderNo()
          if (chkNullEntry(txtOrderNo,"Order No.")) return false;
          return true;
     public boolean validToyId()
          if (chkNullEntry(txtToyId,"Toy Id")) return false;
          return true;
     public boolean chkNullEntry(JTextField aObj,String sDef)
          String s1 = aObj.getText();
          if (s1.length() ==0)
               try
                    JOptionPane.showMessageDialog(sP,sDef+" cannot be left blank","Error Message",JOptionPane.ERROR_MESSAGE);
                    //showStatus(sDef+" cannot be left blank");
                    // nbvvvv vcz     z111111eeeefgggggggggg aObj.requestFocus();
               catch(Exception e)
                    showStatus("Error in chkNullEntry() method");
               return true ;
          else
               return false;
     public boolean validPShopperId()
          if (chkNullEntry(txtShopperId,"Shopper Id")) return false;
          return true;
     public boolean validPPassword()
          if (chkNullEntry(txtPassword,"Password")) return false;
          return true;
// end of code.

Would it not be acceptable to check that each field has a value when Submit is pressed. If a field is found with no data then display the error message and return the focus to the empty field. This would solve the multiple cursors problem as you would not need any focusLost handler code.
If this is entirely out of the question then you will have to override some of the FocusManager methods to prevent the JVM from handling focus for you :
FocusManager.setCurrentManager(new DefaultFocusManager() {
// Override FocusManager methods here.
});Ronny.

Problem with custom control and focus

I've a problem with the focus in a custom control that contains a TextField and some custom nodes.
If i create a form with some of these custom controls i'm not able to navigate through these fields by using the TAB key.
I've implemented a KeyEvent listener on the custom control and was able to grab the focus and forward it to the embedded TextField by calling requestFocus() on the TextField but the problem is that the TextField won't get rid of the focus anymore. Means if i press TAB the first embedded TextField will get the focus, after pressing TAB again the embedded TextField in the next custom control will get the focus AND the former focused TextField still got the focus!?
So i'm not able to remove the focus from an embeded TextField.
Any idea how to do this ?

Here you go, it contains the control, skin and behavior of the custom control, the css file and a test file that shows the problem...
control:
import javafx.scene.control.Control;
import javafx.scene.control.TextField;
public class TestInput extends Control {
    private static final String DEFAULT_STYLE_CLASS = "test-input";
    private TextField           textField;
    private int                 id;
    public TestInput(final int ID) {
        super();
        id = ID;
        textField = new TextField();
        init();
    private void init() {
        getStyleClass().add(DEFAULT_STYLE_CLASS);
    public TextField getTextField() {
        return textField;
    @Override protected String getUserAgentStylesheet() {
            return getClass().getResource("testinput.css").toExternalForm();
    @Override public String toString() {
        return "TestInput" + id + ": " + super.toString();
}skin:
import com.sun.javafx.scene.control.skin.SkinBase;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.EventHandler;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
public class TestInputSkin extends SkinBase<TestInput, TestInputBehavior> {
    private TestInput control;
    private TextField textField;
    private boolean   initialized;
    public TestInputSkin(final TestInput CONTROL) {
        super(CONTROL, new TestInputBehavior(CONTROL));
        control     = CONTROL;
        textField   = control.getTextField();
        initialized = false;
        init();
    private void init() {
        initialized = true;
        paint();
    public final void paint() {
        if (!initialized) {
            init();
        getChildren().clear();
        getChildren().addAll(textField);
    @Override public final TestInput getSkinnable() {
        return control;
    @Override public final void dispose() {
        control = null;
}behavior:
import com.sun.javafx.scene.control.behavior.BehaviorBase;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.EventHandler;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyEvent;
public class TestInputBehavior extends BehaviorBase<TestInput> {
    private TestInput control;
    public TestInputBehavior(final TestInput CONTROL) {
        super(CONTROL);
        control = CONTROL;
        control.getTextField().addEventFilter(KeyEvent.KEY_PRESSED, new EventHandler<KeyEvent>() {
            @Override public void handle(final KeyEvent EVENT) {
                if (KeyEvent.KEY_PRESSED.equals(EVENT.getEventType())) {
                    keyPressed(EVENT);
        control.focusedProperty().addListener(new ChangeListener<Boolean>() {
            @Override public void changed(ObservableValue<? extends Boolean> ov, Boolean wasFocused, Boolean isFocused) {
                if (isFocused) { isFocused(); } else { lostFocus(); }
    public void isFocused() {
        System.out.println(control.toString() + " got focus");
        control.getTextField().requestFocus();
    public void lostFocus() {
        System.out.println(control.toString() + " lost focus");
    public void keyPressed(KeyEvent EVENT) {
        if (KeyCode.TAB.equals(EVENT.getCode())) {
            control.getScene().getFocusOwner().requestFocus();
}the css file:
.test-input {
    -fx-skin: "TestInputSkin";
}and finally the test app:
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.TextField;
import javafx.scene.layout.GridPane;
import javafx.stage.Stage;
public class Test extends Application {
    TestInput input1;
    TestInput input2;
    TestInput input3;
    TextField input4;
    TextField input5;
    TextField input6;
    Scene     scene;
    @Override public void start(final Stage STAGE) {
        setupStage(STAGE, setupScene());
    private Scene setupScene() {
        input1 = new TestInput(1);
        input2 = new TestInput(2);
        input3 = new TestInput(3);
        input4 = new TextField();
        input5 = new TextField();
        input6 = new TextField();
        GridPane pane = new GridPane();
        pane.add(input1, 1, 1);
        pane.add(input2, 1, 2);
        pane.add(input3, 1, 3);
        pane.add(input4, 2, 1);
        pane.add(input5, 2, 2);
        pane.add(input6, 2, 3);
        scene = new Scene(pane);
        return scene;
    private void setupStage(final Stage STAGE, final Scene SCENE) {
        STAGE.setTitle("Test");
        STAGE.setScene(SCENE);
        STAGE.show();
    public static void main(String[] args) {
        launch(args);
The test app shows three custom controls on the left column and three standard textfields on the right column. If you press TAB you will see what i mean...

FocusListener and other listener problem

I don't know why i can't catch Deactivated and LostFocus and other relevant event.
I try to make a simplepanel as Popup because Jpopupmenu have some problem.
please take a look.
regards thanks
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowFocusListener;
import java.awt.event.WindowListener;
import javax.swing.JApplet;
import javax.swing.JButton;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JWindow;
* Created on Jun 1, 2006
* TODO To change the template for this generated file go to
* Window - Preferences - Java - Code Style - Code Templates
* @author varamthanapon
* TODO To change the template for this generated type comment go to Window -
* Preferences - Java - Code Style - Code Templates
public class SampleMain extends JApplet implements ActionListener,
          WindowFocusListener, ComponentListener, WindowListener {
     private JButton m_objJButton = null;
     private PopupPanel m_objPopupPanel = null;
     public SampleMain() {
          this.getContentPane().setLayout(new BorderLayout());
          JPanel mainPanel = new JPanel();
          mainPanel.setSize(500, 500);
          mainPanel.setLocation(500, 500);
          mainPanel.add(new JLabel("XXX"), BorderLayout.NORTH);
          this.getContentPane().add(mainPanel);
          JButton xbutton = new JButton("xxx");
          this.getContentPane().add(xbutton, BorderLayout.WEST);
          xbutton.addActionListener(this);
          m_objPopupPanel = new PopupPanel(this);
          this.addFocusListener(m_objPopupPanel);
          this.show();
     public class PopupPanel extends JWindow implements FocusListener {
          public PopupPanel(SampleMain obj) {
               this.addWindowFocusListener(obj);
               this.addComponentListener(obj);
               this.addWindowListener(obj);
          * (non-Javadoc)
          * @see java.awt.event.FocusListener#focusGained(java.awt.event.FocusEvent)
          public void focusGained(FocusEvent e) {
               // TODO Auto-generated method stub
               JOptionPane.showMessageDialog(new JPanel(), "XXX");
          * (non-Javadoc)
          * @see java.awt.event.FocusListener#focusLost(java.awt.event.FocusEvent)
          public void focusLost(FocusEvent e) {
               // TODO Auto-generated method stub
               JOptionPane.showMessageDialog(new JPanel(), "XXX");
     * (non-Javadoc)
     * @see java.awt.event.ActionListener#actionPerformed(java.awt.event.ActionEvent)
     public void actionPerformed(ActionEvent e) {
          // TODO Auto-generated method stub
          m_objPopupPanel.setSize(200, 50);
          m_objPopupPanel.setLocation(200, 50);
          m_objPopupPanel.show();
     * (non-Javadoc)
     * @see java.awt.event.WindowFocusListener#windowGainedFocus(java.awt.event.WindowEvent)
     public void windowGainedFocus(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowGainedFocus");
     * (non-Javadoc)
     * @see java.awt.event.WindowFocusListener#windowLostFocus(java.awt.event.WindowEvent)
     public void windowLostFocus(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowLostFocus");
     * (non-Javadoc)
     * @see java.awt.event.ComponentListener#componentResized(java.awt.event.ComponentEvent)
     public void componentResized(ComponentEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "componentResized");
     * (non-Javadoc)
     * @see java.awt.event.ComponentListener#componentMoved(java.awt.event.ComponentEvent)
     public void componentMoved(ComponentEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "componentMoved");
     * (non-Javadoc)
     * @see java.awt.event.ComponentListener#componentShown(java.awt.event.ComponentEvent)
     public void componentShown(ComponentEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "componentShown");
     * (non-Javadoc)
     * @see java.awt.event.ComponentListener#componentHidden(java.awt.event.ComponentEvent)
     public void componentHidden(ComponentEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "componentHidden");
     * (non-Javadoc)
     * @see java.awt.event.WindowListener#windowOpened(java.awt.event.WindowEvent)
     public void windowOpened(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowOpened");
     * (non-Javadoc)
     * @see java.awt.event.WindowListener#windowClosing(java.awt.event.WindowEvent)
     public void windowClosing(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowClosing");
     * (non-Javadoc)
     * @see java.awt.event.WindowListener#windowClosed(java.awt.event.WindowEvent)
     public void windowClosed(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowClosed");
     * (non-Javadoc)
     * @see java.awt.event.WindowListener#windowIconified(java.awt.event.WindowEvent)
     public void windowIconified(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowIconified");
     * (non-Javadoc)
     * @see java.awt.event.WindowListener#windowDeiconified(java.awt.event.WindowEvent)
     public void windowDeiconified(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowDeiconified");
     * (non-Javadoc)
     * @see java.awt.event.WindowListener#windowActivated(java.awt.event.WindowEvent)
     public void windowActivated(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowActivated");
     * (non-Javadoc)
     * @see java.awt.event.WindowListener#windowDeactivated(java.awt.event.WindowEvent)
     public void windowDeactivated(WindowEvent e) {
          // TODO Auto-generated method stub
          JOptionPane.showMessageDialog(new JPanel(), "windowDeactivated");
}

I believe it's because Windows which don't have a visible parent frame are, by default, not focusable. Therefore they're never activated or focused.
For the window to become focusable it needs a visible parent. Have a look at Window.isFocusableWindow method's Javadoc for information about how this works.
There's also no point trying to force the window to be focusable using setFocusableWindowState - it still won't work without the visible parent frame.
What's the problem with JPopupMenu? It seems unlikely that you'll write something better than that.
Alternatively, you could try using an undecorated JDialog. Personally, I'd try resolving your differences with JPopupMenu!
Hope this helps.

DataGridColumn labelFunction Problem

I am trying to get the DataGrid to behave normally, as most
DataGrids do. Here's the setup....
For example:
ColumnA: Qty. (default value: 0)
ColumnB: Price (default value: 9.99)
ColumnC: (ColumnA * ColumnB)
In this case I'm using a labelFunction to calculate ColumnC.
When I run the program and select ColumnA (Qty.) and I change the
value from 0 to 1 and I hit the "ENTER" key, the calculation is
executed and ColumnC is updated as expected. But, if I hit the
"TAB" key instead, it moves the focus to the next editable cell on
that row, but it does not execute the calculation (labelFunction).
This to me seems like it should be a given, since most DataGrids in
most development platforms support this type of behavior (execute
on lostfocus/leavecell, etc). But, it looks like it's not built
into Flex 2.0's DataGrid.
My other thought, was to try to capture the "Leave Cell"
event....I was unable to find a "Leave Cell" event.
Any thoughts, ideas or suggestions would be greatly
appreciated!
- Mike

Well, my solution works only if you're not using any other
controls (as I just found out). Basically, this solution prevents
the user from ever moving the focus out to any other control.
So far, my experience with the implementation of the Datagrid
in Flex has been filled with frustration. There are a bunch of
"common" scenarios that are proving very difficult to implement.
For example:
1) It would be nice to be able to have a calculated column
that works. (I set up a labelfunction, but this doesn't update
until I leave the row, rather than leave a cell, also it doesn't
trigger when using the tab key...see #3).
2) It would be nice to be able to add a combobox to a
datagrid column (I know Flex can do this, but not easily, or
intuitively).
3) It would be nice to be able to control the tabbing
behavior in the datagrid, it's doesn't work as one would expect it
to. (I set focus to cell in code, then when I hit the tab key, it
moves the tab out of the datagrid. When I click back into the
datagrid and hit the tab key again...it works as I would expect.
But, when I update data in a column and tab off it doesn't trigger
the itemEditEnd event...and unfortunately there is no cell edit end
event).
I could go on, but those are my Top 3 problems right now. If
anyone has suggestions, ideas or solutions I would love to hear
them.
Thanks,
- Mike

A problem with threads

I am trying to implement some kind of a server listening for requests. The listener part of the app, is a daemon thread that listens for connections and instantiates a handling daemon thread once it gets some. However, my problem is that i must be able to kill the listening thread at the user's will (say via a sto button). I have done this via the Sun's proposed way, by testing a boolean flag in the loop, which is set to false when i wish to kill the thread. The problem with this thing is the following...
Once the thread starts excecuting, it will test the flag, find it true and enter the loop. At some point it will LOCK on the server socket waiting for connection. Unless some client actually connects, it will keep on listening indefinatelly whithought ever bothering to check for the flag again (no matter how many times you set the damn thing to false).
My question is this: Is there any real, non-theoretical, applied way to stop thread in java safely?
Thank you in advance,
Lefty

This was one solution from the socket programming forum, have you tried this??
public Thread MyThread extends Thread{
     boolean active = true;
     public void run(){
          ss.setSoTimeout(90);
          while (active){
               try{
                    serverSocket = ss.accept();
               catch (SocketTimeoutException ste){
               // do nothing
     // interrupt thread
     public void deactivate(){
          active = false;
          // you gotta sleep for a time longer than the
          // accept() timeout to make sure that timeout is finished.
          try{
               sleep(91);
          }catch (InterruptedException ie){
          interrupt();
}

A problem with Threads and MMapi

I am tring to execute a class based on Game canvas.
The problem begin when I try to Play both a MIDI tone and to run an infinit Thread loop.
The MIDI tone "Stammers".
How to over come the problem?
Thanks in advance
Kobi
See Code example below:
import java.io.IOException;
import java.io.InputStream;
import javax.microedition.lcdui.Graphics;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.game.GameCanvas;
import javax.microedition.media.Manager;
import javax.microedition.media.MediaException;
import javax.microedition.media.Player;
public class MainScreenCanvas extends GameCanvas implements Runnable {
     private MainMIDlet parent;
     private boolean mTrucking = false;
     Image imgBackgound = null;
     int imgBackgoundX = 0, imgBackgoundY = 0;
     Player player;
     public MainScreenCanvas(MainMIDlet parent)
          super(true);
          this.parent = parent;
          try
               imgBackgound = Image.createImage("/images/area03_bkg0.png");
               imgBackgoundX = this.getWidth() - imgBackgound.getWidth();
               imgBackgoundY = this.getHeight() - imgBackgound.getHeight();
          catch(Exception e)
               System.out.println(e.getMessage());
      * starts thread
     public void start()
          mTrucking = true;
          Thread t = new Thread(this);
          t.start();
      * stops thread
     public void stop()
          mTrucking = false;
     public void play()
          try
               InputStream is = getClass().getResourceAsStream("/sounds/scale.mid");
               player = Manager.createPlayer(is, "audio/midi");
               player.setLoopCount(-1);
               player.prefetch();
               player.start();
          catch(Exception e)
               System.out.println(e.getMessage());
     public void run()
          Graphics g = getGraphics();
          play();
          while (true)
               tick();
               input();
               render(g);
      * responsible for object movements
     private void tick()
      * response to key input
     private void input()
          int keyStates = getKeyStates();
          if ((keyStates & LEFT_PRESSED) != 0)
               imgBackgoundX++;
               if (imgBackgoundX > 0)
                    imgBackgoundX = 0;
          if ((keyStates & RIGHT_PRESSED) != 0)
               imgBackgoundX--;
               if (imgBackgoundX < this.getWidth() - imgBackgound.getWidth())
                    imgBackgoundX = this.getWidth() - imgBackgound.getWidth();
      * Responsible for the drawing
      * @param g
     private void render(Graphics g)
          g.drawImage(imgBackgound, imgBackgoundX, imgBackgoundY, Graphics.TOP | Graphics.LEFT);
          this.flushGraphics();
}

You can also try to provide a greater Priority to your player thread so that it gains the CPU time when ever it needs it and don't harm the playback.
However a loop in a Thread and that to an infinite loop is one kind of very bad programming, 'cuz the loop eats up most of your CPU time which in turn adds up more delays of the execution of other tasks (just as in your case it is the playback). By witting codes bit efficiently and planning out the architectural execution flow of the app before start writing the code helps solve these kind of issues.
You can go through [this simple tutorial|http://oreilly.com/catalog/expjava/excerpt/index.html] about Basics of Java and Threads to know more about threads.
Regds,
SD
N.B. And yes there are more articles and tutorials available but much of them targets the Java SE / EE, but if you want to read them here is [another great one straight from SUN|http://java.sun.com/docs/books/tutorial/essential/concurrency/index.html] .
Edited by: find_suvro@SDN on 7 Nov, 2008 12:00 PM

J2ME problem with threads

Hi all,
I would like to ask you for a help. I need to write a small program at my university. I started to write a midlet which function would be to countdown time for sports activities. I woul like to start a new thread - the one that counts down - and at the same time make the main thread sleep. After the "countdown" thread finishes, the main thread wakes up and waits for user input. The problem is that when the "countdown" thread finishes his work, I've got Uncaught exception java/lang/NullPointerException. error and the midlet halts.
Below you can find the code
import java.lang.*;
import java.util.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
public class intervals extends MIDlet implements CommandListener
public Display ekran;
private SweepCanvas sweeper;
private Form rundy;
private TextField round0, round1, round2, round3, round4, round5, round6, round7, round8;
private long czas,x;
private Command exitCommand;
private Command addRound;
private Command delRound;
private Command start;
private TextField repeat;
private Form odliczanie;
private Alert ostrz;
Licznik thread;
String test;
StringItem test1;
int parz,i,j,k;
static int l;
int ilrund;
int ilpowt;
Item sec;
long sec1;
public intervals()
    rundy = new Form("Interwały sportowe");
    exitCommand = new Command("Wyjście", Command.EXIT, 2);
    addRound = new Command("Dodaj","Dodaj rundę", Command.ITEM,1);
    delRound = new Command("Usuń","Usuń ostatnią rundę", Command.ITEM,1);
    start = new Command("Start", Command.ITEM,1);
    odliczanie = new Form("Odliczanie");
    TextField dodaj(TextField kolej)
        kolej=new TextField("Podaj czas (s) rundy "+parz,null, 4, TextField.NUMERIC);//stworzenie nowej instancji do wybierania czasu trwania rundy
        if(rundy.size()==0)
            rundy.insert(rundy.size(),kolej);
            else
                rundy.insert(rundy.size()-1, kolej);
        return kolej;
    void odliczanie(TextField round)
        monitor m=new monitor();
        k=Integer.parseInt(round.getString());
        ekran.setCurrent(odliczanie);
        thread=new Licznik(k,odliczanie);
        thread.start();
        ekran.setCurrent(rundy);
public void startApp()// throws MIDletStateChangeException
    rundy.deleteAll();
    repeat = new TextField("Podaj ilość powtórzeń",null,1,TextField.NUMERIC);
    rundy.addCommand(addRound);
    rundy.addCommand(exitCommand);
    rundy.setCommandListener(this);
    Canvas obrazek = new MyCanvas();
    ekran = Display.getDisplay(this);
    ekran.setCurrent(obrazek);
    czas=System.currentTimeMillis();
    while (System.currentTimeMillis()<czas+1000)
        continue;
    ekran.setCurrent(rundy);
public void pauseApp()
public void destroyApp(boolean unconditional)
    notifyDestroyed();
public void commandAction(Command c, Displayable s)
    if (c == exitCommand)
        destroyApp(false);
        notifyDestroyed();
    else if(c==addRound)
        if(rundy.size()==0)//Sprawdzenie ilości elementów w celu poprawnego wyświetlania liczby rund w formie
            parz=1;
            else
            parz=rundy.size();
        switch(parz)
            case 1:
                round0=dodaj(round0);break;
            case 2:
                round1=dodaj(round1);break;
            case 3:
               round2= dodaj(round2);break;
            case 4:
                round3=dodaj(round3);break;
            case 5:
                round4=dodaj(round4);break;
            default:
                ostrz=new Alert("Uwaga","Maksymalna liczba rund wynosi 9", null, AlertType.INFO);
                ostrz.setTimeout(3000);
                ekran.setCurrent(ostrz);
        if(rundy.size()==1)
            rundy.append(repeat);
            rundy.addCommand(start);
        rundy.addCommand(delRound);
    else if(c==delRound)
        if(rundy.size()!=0)
            rundy.delete(rundy.size()-2);
            if (rundy.size()==1)
                rundy.deleteAll();
            if(rundy.size()==0)
                rundy.removeCommand(delRound);
                rundy.removeCommand(start);
    else if(c==start)
        ilrund=rundy.size()-1;
        if(this.repeat.size()>0)
            ilpowt=Integer.parseInt(this.repeat.getString());
        ekran = Display.getDisplay(this);
        for (i=1; i<=ilpowt;i++)
            odliczanie= new Form("Odliczanie");
             for (j=0;j<ilrund;j++)
                switch(j)
                     case 0:
                         odliczanie(round0);
                         break;
                     case 1:
                         odliczanie(round1);
                         break;
                     case 2:
                         odliczanie(round2);
                         break;
                     case 3:
                         odliczanie(round3);
                         break;
                     case 4:
                         odliczanie(round4);
                         break;
                     case 5:
                         odliczanie(round5);
                         break;
                     case 6:
                         odliczanie(round6);
                         break;
                     case 7:
                         odliczanie(round7);
                         break;
                     case 8:
                         odliczanie(round8);
                         break;
class Licznik extends Thread
    int czas1,k;
    Form forma;
    monitor m;
    public Licznik(int k,Form formap)
        czas1=k;
        forma=formap;
    public synchronized void run()
        while(czas1>0)
            forma.deleteAll();
            forma.append("Czas pozostały (s): "+czas1);
            try{Thread.sleep(1000);} catch(InterruptedException e){e.printStackTrace();}
            czas1--;
        if(czas1<=0)
            m.put();
    }and monitor class
public class monitor
boolean busy=false;
synchronized void get()
    if(!busy)
        try
            wait();
        }catch(InterruptedException e){e.printStackTrace();}
    notify();
synchronized void put()
    if(busy)
        try
        wait();
        }catch(InterruptedException e){e.printStackTrace();}
    busy=true;
    notify();
}Can anybody help me with this?

Groovemaker,
Your Licznik class has a member m of type monitor, which has not been instantiated (in other words is null) hence, when calling m.put() you get NullPointerException. Please also mind, that using Thread.sleep(1000) is not an accurate way of measuring time.
If I may, please use recommended for Java class naming conventions - some of your names use lower case, while other don't which is confusing to the reader.
Daniel

Problem with threads within applet

Hello,
I got an applet, inside this applet I have a singleton, inside this singleton I have a thread.
this thread is running in endless loop.
he is doing something and go to sleep on and on.
the problem is,
when I refresh my IE6 browser I see more than 1 thread.
for debug matter, I did the following things:
inside the thread, sysout every time he goes to sleep.
sysout in the singleton constructor.
sysout in the singleton destructor.
the output goes like this:
when refresh the page, the singleton constructor loading but not every refresh, sometimes I see the constructor output and sometimes I dont.
The thread inside the singleton is giving me the same output, sometime I see more than one thread at a time and sometimes I dont.
The destructor never works (no output there).
I don't understand what is going on.
someone can please shed some light?
thanks.
btw. I am working with JRE 1.1
this is very old and big applet and I can't convert it to something new.

Ooops. sorry!
I did.
     public void start() {
     public void stop() {
     public void destroy() {
          try {
               resetAll();
               Configuration.closeConnection();
               QuoteItem.closeConnection();
          } finally {
               try {
                    super.finalize();
               } catch (Throwable e) {
                    e.printStackTrace();
     }

Problem with Threads and a static variable

I have a problem with the code below. I am yet to make sure that I understand the problem. Correct me if I am wrong please.
Code functionality:
A timer calls SetState every second. It sets the state and sets boolean variable "changed" to true. Then notifies a main process thread to check if the state changed to send a message.
The problem as far I understand is:
Assume the timer Thread calls SetState twice before the main process Thread runs. As a result, "changed" is set to true twice. However, since the main process is blocked twice during the two calls to SetState, when it runs it would have the two SetState timer threads blocked on its synchronized body. It will pass the first one, send the message and set "changed" to false since it was true. Now, it will pass the second thread, but here is the problem, "changed" is already set to false. As a result, it won't send the message even though it is supposed to.
Would you please let me know if my understanding is correct? If so, what would you propose to resolve the problem? Should I call wait some other or should I notify in a different way?
Thanks,
B.D.
Code:
private static volatile boolean bChanged = false;
private static Thread objMainProcess;
   protected static void Init(){
        objMainProcess = new Thread() {
            public void run() {
                while( objMainProcess == Thread.currentThread() ) {
                   GetState();
        objMainProcess.setDaemon( true );
        objMainProcess.start();
    public static void initStatusTimer(){
        if(objTimer == null)
             objTimer = new javax.swing.Timer( 1000, new java.awt.event.ActionListener(){
                public void actionPerformed( java.awt.event.ActionEvent evt){
                          SetState();
    private static void SetState(){
        if( objMainProcess == null ) return;
        synchronized( objMainProcess ) {
            bChanged = true;
            try{
                objMainProcess.notify();
            }catch( IllegalMonitorStateException e ) {}
    private static boolean GetState() {
        if( objMainProcess == null ) return false;
        synchronized( objMainProcess ) {
            if( bChanged) {
                SendMessage();
                bChanged = false;
                return true;
            try {
                objMainProcess.wait();
            }catch( InterruptedException e ) {}
            return false;
    }

Thanks DrClap for your reply. Everything you said is right. It is not easy to make them alternate since SetState() could be called from different places where the state could be anything else but a status message. Like a GREETING message for example. It is a handshaking message but not a status message.
Again as you said, There is a reason I can't call sendMessage() inside setState().
The only way I was able to do it is by having a counter of the number of notifies that have been called. Every time notify() is called a counter is incremented. Now instead of just checking if "changed" flag is true, I also check if notify counter is greater than zero. If both true, I send the message. If "changed" flag is false, I check again if the notify counter is greater than zero, I send the message. This way it works, but it is kind of a patch than a good design fix. I am yet to find a good solution.
Thanks,
B.D.

Problem with threads running javaw

Hi,
Having a problem with multi thread programming using client server sockets. The program works find when starting the the application in a console using java muti.java , but when using javaw multi.java the program doesnt die and have to kill it in the task manager. The program doesnt display any of my gui error messages either when the server disconnect the client. all works find in a console. any advice on this as I havent been able to understand why this is happening? any comment would be appreciated.
troy.

troy,
Try and post a minimum code sample of your app which
does not work.
When using javaw, make sure you redirect the standard
error and standard output streams to file.
Graeme.Hi Graeme,
I dont understand what you mean by redirection to file? some of my code below.
The code works fine under a console, code is supposed to exit when the client (the other server )disconnects. the problem is that but the clientworker side of the code still works. which under console it doesnt.
public class Server{
ServerSocket aServerSocket;
Socket dianosticsSocket;
Socket nPortExpress;
ClientListener aClientListener;
LinkedList queue = new LinkedList();
int port = 0;
int clientPort = 0;
String clientName = null;
boolean serverAlive = true;
* Server constructor generates a server
* Socket and then starts a client threads.
* @param aPort      socket port of local machine.
public Server(int aPort, String aClientName, int aClientPort){
port = aPort;
clientName = aClientName;
clientPort = aClientPort;
try{
// create a new thread
aServerSocket = new ServerSocket(port) ;
// connect to the nPortExpress
aClientListener = new ClientListener(InetAddress.getByName(clientName), clientPort, queue,this);
// aClientListener.setDaemon(true);
aClientListener.start();
// start a dianostic port
DiagnosticsServer aDiagnosticsServer = new DiagnosticsServer(port,queue,aClientListener);
// System.out.println("Server is running on port " + port + "...");
// System.out.println("Connect to nPort");
catch(Exception e)
// System.out.println("ERROR: Server port " + port + " not available");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Server port " + port + " not available", JOptionPane.ERROR_MESSAGE);
serverAlive = false;
System.exit(1);
while(serverAlive&&aClientListener.hostSocket.isConnected()){
try{
// connect the client
Socket aClient = aServerSocket.accept();
//System.out.println("open client connection");
//System.out.println("client local: "+ aClient.getLocalAddress().toString());
// System.out.println("client localport: "+ aClient.getLocalPort());
// System.out.println("client : "+ aClient.getInetAddress().toString());
// System.out.println("client port: "+ aClient.getLocalPort());
// make a new client thread
ClientWorker clientThread = new ClientWorker(aClient, queue, aClientListener, false);
// start thread
clientThread.start();
catch(Exception e)
//System.out.println("ERROR: Client connection failure");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Client connection failure", JOptionPane.ERROR_MESSAGE);
}// end while
} // end constructor Server
void serverExit(){
     JOptionPane.showMessageDialog(null, "Server ","ERROR: nPort Failure", JOptionPane.ERROR_MESSAGE);
     System.exit(1);
}// end class Server
*** connect to another server
public class ClientListener extends Thread{
InetAddress hostName;
int hostPort;
Socket hostSocket;
BufferedReader in;
PrintWriter out;
boolean loggedIn;
LinkedList queue;      // reference to Server queue
Server serverRef; // reference to main server
* ClientListener connects to the host server.
* @param aHostName is the name of the host eg server name or IP address.
* @param aHostPort is a port number of the host.
* @param aLoginName is the users login name.
public ClientListener(InetAddress aHostName, int aHostPort,LinkedList aQueue,Server aServer)      // reference to Server queue)
hostName = aHostName;
hostPort = aHostPort;
queue = aQueue;
serverRef = aServer;
// connect to the server
try{
hostSocket = new Socket(hostName, hostPort);
catch(IOException e){
//System.out.println("ERROR: Connection Host Failed");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Connection to nPort Failed", JOptionPane.ERROR_MESSAGE);
System.exit(0);
} // end constructor ClientListener
** multi client connection server
ClientWorker(Socket aSocket,LinkedList aQueue, ClientListener aClientListener, boolean diagnostics){
queue = aQueue;
addToQueue(this);
client = aSocket;
clientRef = aClientListener;
aDiagnostic = diagnostics;
} // end constructor ClientWorker
* run method is the main loop of the server program
* in change of handle new client connection as well
* as handle all messages and errors.
public void run(){
boolean alive = true;
String aSubString = "";
in = null;
out = null;
loginName = "";
loggedIn = false;
while (alive && client.isConnected()&& clientRef.hostSocket.isConnected()){
try{
in = new BufferedReader(new InputStreamReader(client.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(client.getOutputStream()));
if(aDiagnostic){
out.println("WELCOME to diagnostics");
broadCastDia("Connect : diagnostics "+client.getInetAddress().toString());
out.flush();
else {
out.println("WELCOME to Troy's Server");
broadCastDia("Connect : client "+client.getInetAddress().toString());
     out.flush();
String line;
while(((line = in.readLine())!= null)){
StringTokenizer aStringToken = new StringTokenizer(line, " ");
if(!aDiagnostic){
broadCastDia(line);
clientRef.sendMessage(line); // send mesage out to netExpress
out.println(line);
out.flush();
else{
if(line.equals("GETIPS"))
getIPs();
else{
clientRef.sendMessage(line); // send mesage out to netExpress
out.println(line);
out.flush();
} // end while
catch(Exception e){
// System.out.println("ERROR:Client Connection reset");
                         JOptionPane.showMessageDialog(null, (e.toString()),"ERROR:Client Connection reset", JOptionPane.ERROR_MESSAGE);
try{
if(aDiagnostic){
broadCastDia("Disconnect : diagnostics "+client.getInetAddress().toString());
out.flush();
else {
broadCastDia("Disconnect : client "+client.getInetAddress().toString());
     out.flush();
// close the buffers and connection;
in.close();
out.close();
client.close();
// System.out.println("out");
// remove from list
removeThreadQueue(this);
alive = false;
catch(Exception e){
// System.out.println("ERROR: Client Connection reset failure");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Client Connection reset failure", JOptionPane.ERROR_MESSAGE);
}// end while
} // end method run
* method run - Generates io stream for communicating with the server and
* starts the client gui. Run also parses the input commands from the server.
public void run(){
boolean alive = true;
try{
// begin to life the gui
// aGuiClient = new ClientGui(hostName.getHostName(), hostPort, loginName, this);
// aGuiClient.show();
in = new BufferedReader(new InputStreamReader(hostSocket.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(hostSocket.getOutputStream()));
while (alive && hostSocket.isConnected()){
String line;
while(((line = in.readLine())!= null)){
System.out.println(line);
broadCast(line);
} // end while
} // end while
catch(Exception e){
//     System.out.println("ERRORa Connection to host reset");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Connection to nPort reset", JOptionPane.ERROR_MESSAGE);
try{
hostSocket.close();
     }catch(Exception a){
     JOptionPane.showMessageDialog(null, (a.toString()),"ERROR: Exception", JOptionPane.ERROR_MESSAGE);
alive = false;
System.exit(1);
} // end method run

Problem with Threads and "plase wait..."-Window

Hi everyone,
I have a problem that I'm not able to solve in any way... I have a time-consuming task (a file decryption) which I execute in a separate thread; I've used the SwingWorker class, like suggested by sun-tutorial, and it works right. The problem is that I have to wait that the decryption have finished before continuing with program-execution. Therefore I would like to display a "please wait"-window while the task runs. I've tryed all the possible ways I know but the problem is always the same: the waitWindow is displayed empty, the bounds are painted but the contents no; it's only painted when the decrypt-task has finished. Please help me, I have no more resources....
decrypt-file code:
public class DecryptFile {
private String cryptedFileNameAndPath;
private ByteArrayInputStream resultStream = null;
// need for progress
private int lengthOfTask;
private int current = -1;
private String statMessage;
public DecryptFile(String encZipFileNameAndPath) {
    cryptedFileNameAndPath = encZipFileNameAndPath;
    //Compute length of task...
    // 0 for indeterminate
    lengthOfTask = 0;
public ByteArrayInputStream getDecryptedInputStream() {
    return this.resultStream;
   * Called from ProgressBarDemo to start the task.
public void go() {
    current = -1;
    final SwingWorker worker = new SwingWorker() {
      public Object construct() {
        return new ActualTask();
    worker.start();
   * Called from ProgressBarDemo to find out how much work needs
   * to be done.
public int getLengthOfTask() {
    return lengthOfTask;
   * Called from ProgressBarDemo to find out how much has been done.
public int getCurrent() {
    return current;
public void stop() {
    current = lengthOfTask;
   * Called from ProgressBarDemo to find out if the task has completed.
public boolean done() {
    if (current >= lengthOfTask)
      return true;
    else
      return false;
public String getMessage() {
    return statMessage;
   * The actual long running task. This runs in a SwingWorker thread.
class ActualTask {
    ActualTask () {
      current = -1;
      statMessage = "";
      resultStream = AIUtil.getInputStreamFromEncZip(cryptedFileNameAndPath); //here the decryption happens
      current = 0;
      statMessage = "";
}The code that calls decryption and displays waitWindow
      final WaitSplash wS = new WaitSplash("Please wait...");
      final DecryptFile cryptedTemplate = new DecryptFile (this.templateFile);
      cryptedTemplate.go();
      while (! cryptedTemplate.done()) {
        try {
          wait();
        } catch (Exception e) { }
      this.templateInputStream = cryptedTemplate.getDecryptedInputStream();
      wS.close();Thanks, thanks, thanks in advance!
Edoardo

Maybe you can try setting the priority of the long-running thread to be lower? so that the UI will be more responsive...

Problem with threads in j2me

im using jdk 1.6 with java wtk 2.1
ya i know..
2.1 is a jdk1.4 source
but im using souce as 1.4 during compiliation so thats not the prob
this is my code
package org.learn;
import javax.microedition.midlet.MIDlet;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.Display;
public class thtest extends MIDlet
Thread t;
public void startApp()
Alert a=new Alert("hello");
a.setString("hello");
Alert b=new Alert("world");
b.setString("world");
Display d = Display.getDisplay(this );
d.setCurrent(a);
t=Thread.currentThread();
try{
t.sleep(10000);
catch (Exception e){}
d.setCurrent(b);
public void pauseApp()
public void destroyApp(boolean unconditional)
its just supposed to pause between the alerts using threads
however when i run it using the wtk, the emulator run properly but when i launch the app, it stops executing giving me this:
"Error verifying method org/learn/thtest startApp()V
Approximate bytecode offset 49: Inconsistent or missing stackmap at target
%the stack info%
Execution completed.
437782 bytecodes executed
9 thread switches
486 classes in the system (including system classes)
2506 dynamic objects allocated (73832 bytes)
2 garbage collections (60652 bytes collected)
Execution completed.
437782 bytecodes executed
9 thread switches
486 classes in the system (including system classes)
ALERT: java/lang/VerifyError: org/learn/thtest.
2506 dynamic objects allocated (73832 bytes)
2 garbage collections (60652 bytes collected)
please can someone help me out with this, is it an error on my part or do i have to set some option.

Hi gandalf123,
First, Thread.sleep is a static method, so you don't need to create a Thread object to use it.
I think the problem is due to the fact you don't preverify your midlet.
More over, you don't need to double post your question.

Problem with threads and camera.

Hi everybody!
I've a problem with taking snapshot.
I would like to display a loading screen after it take snapshot ( sometimes i
have to wait few seconds after i took snapshot. Propably photo is being taken in time where i have to wait).
I was trying to use threads but i didn't succeed.
I made this code:
display.setCurrent(perform);
        new Thread(new Runnable(){
            public void run() {
                while((!performing.isShown()) && (backgroundCamera.isShown())){
                    Thread.yield();
                notifyAll();
        }).start();
        new Thread(new Runnable(){
            public void run() {
                try {
                    this.wait();
                } catch(Exception e) {
                    exceptionHandler(e);
                photo = camera.snapshot();
                display.setCurrent(displayPhoto);
        }).start();This code is sometimes showing performing screen but sometimes no.
I don't know why. In my opinion performing.isShown() method isn't working correctly.
Does anyone have some idea how to use threads here?

Hi,
I've finally managed to work this fine.
The code:
       Object o = new Object();
       display.setCurrent(perform);
        new Thread(new Runnable(){
            public void run() {
                while(!performing.isShown()){
                    Thread.yield();
               synchronized(o) {
                  o.notify();
        }).start();
        new Thread(new Runnable(){
            public void run() {
                try {
                    synchronized(o) {
                       o.wait(1);
                } catch(Exception e) {
                    exceptionHandler(e);
                photo = camera.snapshot();
                display.setCurrent(displayPhoto);
        }).start();

Problem with threads and graphics

I have a thread that chooses paths for a Travelling salesman problem, it then calls a TSPdraw class and passes it the path, which the class then draws. the problem is when i have two threads it creates two windows but only draws a path in one of them. any ideas where i`m going wrong

Are you using swing components? Swing isn't threadsafe. If you have multiple threads that want to update your UI you need to use the SwingUtilities.invokeLater(...)or invokeAndWait(...). There is a page in the swing tutorial about this at: http://java.sun.com/docs/books/tutorial/uiswing/misc/threads.html

LostFocus problem

Similar Messages

Maybe you are looking for