How Java handle event??

for example,An application want to receive the event of KeyBoard,The event Should be received by OS ,I think.and Then??OS Should send the event to Where ?? Who would receive the event??Wher does Application receive the event ??

He, I now I remind : Look at the end of
http://forum.java.sun.com/thread.jsp?forum=57&thread=293208
But note that there is no unique response to your question: It's hihgly dependant of your JVM and of your OS.

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    Hi Chandan,
    possibly you are not just new to ABAP but new to obeject oriented programming in general. In oo, you use events to trigger methods that are registered as 'listeners' for the event.
    As I have no idea on your current knowledge, I don't know what I could recommend to start with.
    My personal approach is first to have a task I want to complete and then find and understand the methods to get there.
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    Windows can be closed in a number of ways and the simplest way to trap them would be to handle Window Closing in code behind.
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    chxAllowToClose.IsChecked
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  • How to handle events in J Table (Enter event)

    I created a J Table having multiple rows and columns. I want to have the event to happen on second column, on entering the code on first column, and then pressing ENTER.
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    This code would do your work
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    import java.awt.event.*;
    import javax.swing.*;
    import javax.swing.event.*;
    import javax.swing.table.*;
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        private JTable table;
        private AbstractTableModel model;
        private DefaultTableModel defaultModel;
        private JScrollPane jsp;
        public TestTable()
            table = new JTable();
            defaultModel = new DefaultTableModel(10,5);
            setModel(defaultModel);
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            hookSetTextOnEnter();
        protected void hookSetTextOnEnter()
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                    int row = table.getSelectedRow();
                    int column = table.getSelectedColumn();
                    System.out.println(" SELECTING NEXT ROW "+row+""+column);
                    if(row != -1 && column == 2 )
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        public JScrollPane getScrollPane()
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        public JTable getTable()
            return table;
        public static void main(String[] args)
            TestTable tt = new TestTable();
            JFrame frame = new JFrame("Test Table");
            frame.getContentPane().add(tt.getScrollPane());
            frame.pack();
            frame.setVisible(true);
    }------- Unformatted Version------------
    import java.awt.*;
    import java.awt.event.*;
    import javax.swing.*;
    import javax.swing.event.*;
    import javax.swing.table.*;
    public class TestTable
    private JTable table;
    private AbstractTableModel model;
    private DefaultTableModel defaultModel;
    private JScrollPane jsp;
    public TestTable()
    table = new JTable();
    defaultModel = new DefaultTableModel(10,5);
    setModel(defaultModel);
    jsp = new JScrollPane(table);
    hookSetTextOnEnter();
    protected void hookSetTextOnEnter()
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    final Action enterAction = table.getActionMap().get(actionName);
    Action myAction = new AbstractAction()
    public void actionPerformed(ActionEvent e)
    int row = table.getSelectedRow();
    int column = table.getSelectedColumn();
    System.out.println(" SELECTING NEXT ROW "+row+""+column);
    if(row != -1 && column == 2 )
    Object value = table.getValueAt(row,column);
    if(value != null && value.toString().equals("A010"))
    table.setValueAt("HIGH TENSION CABEL",row,column+1);
    enterAction.actionPerformed(e);
    table.getActionMap().put(actionName,myAction);
    public void setModel(TableModel model)
    table.setModel(model);
    public JScrollPane getScrollPane()
    return jsp;
    public JTable getTable()
    return table;
    public static void main(String[] args)
    TestTable tt = new TestTable();
    JFrame frame = new JFrame("Test Table");
    frame.getContentPane().add(tt.getScrollPane());
    frame.pack();
    frame.setVisible(true);
    Thanks,
    Kalyan

  • How to handle event when the user closing the browser (Urgent Please)

    Hi,
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    Finally got this working. You cannot use the stop() or destroy methods. By the time they are called all database connections are gone and you will get a null pointer exception.
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    </SCRIPT>
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    public void doSave()
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  • How to handle events in Swng

    Hi!
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    Method 1
    Write annonymus inner classes in the same class
    Method 2
    =======
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    1. Your JFrame is now subject to receive action events from anywhere. You will have to be more careful that you respond only to the right events.
    2. If you have a lot of possible consequences to an event(for example, based on button pressed), you'll need a long if...then...else statement to determine what to do based on the source of the event.
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  • How to handle events in webdynpro abap

    Hi,
    can any body explain how to handle the events in webdynpro abap.
    i want to know some concepts in general.
    Thanks,

    Hi Mahesh,
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    you can also create events in your component controller and they can be handled within your views
    check cl_wd_custom_event class for details about what all information you get when an event occurs.
    for further details you can check out the following links
    http://help.sap.com/saphelp_nw04s/helpdata/en/eb/ed6f4169e25858e10000000a1550b0/frameset.htm
    http://help.sap.com/saphelp_nw04s/helpdata/en/a9/c751415e3b6532e10000000a1550b0/frameset.htm
    also you can try the tutorial at the following link for further clarity
    https://www.sdn.sap.com/irj/sdn/go/portal/prtroot/docs/library/uuid/2eb11b59-0a01-0010-dfa3-8292abdf9c4f
    Regards,
    Shweta
    Message was edited by:
            Shweta R Shanbhag

  • How to handle events between two custom components?

    Hi ,
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    Events don't really go sideways in ActionScript by default. They bubble upward. If you want to send an event sideways, you will probably have to coordinate with something higher up in the event hierarchy. You can send the event to a common ancestor, and then pass it down the hierarchy as a method argument.
    Another option is to use a framework that supports Injection. There are a number around these days. The one I'm most familiar with is Mate, which allows you to handle events and inject data in MXML. Mate is meant to be used as an MVC framework, and you may want to look into it if your application is complex, but you can also use it to coordinate global event handling if you don't need that level of structure.

  • How to handle events when artboard list change in Illustrator?

    It is very strange for me, but AIEvent has no event type for handle artboard list change events.
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  • How to handle event structures for two buttons and two counters.

         *I have two buttons A and B, and have to compare the difference in hits between them.  So do I place an event structure within a while loop for each button (2 buttons, 2 event structures, 2 while loops), or does it need to be one event structure with cases for both buttons whithin one while loop? 
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    You should probably have not started a new thread and waited until your question in the original thread was answered. You can modify altenbach's example for a second button. You have a single event structure with a new event for the second button. You have a second shift register to track the number of times the second button is pressed. Inside the while loop but outside the event structure, you just have a subtract function in or to report the difference. do not modify the posted example for the stop button. It works perfectly as is.

  • How to handle event in MVVM ?

    Hi everyone ,
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    Thank you

    Windows can be closed in a number of ways and the simplest way to trap them would be to handle Window Closing in code behind.
    This is also the easiest way to show dialogs if that's how you wanted the warning message to appear.
    This:
    chxAllowToClose.IsChecked
    Looks like a checkbox to me, seeing as you have IsChecked.
    That presumably means you already have that bound to a viewmodel and visible to the user.
    You can therefore just test that value from the view.
    If you prefer to hide that instead then there are several options.
    You could have a dependency property and a binding in code behind which binds to the viewmodel. Test that in your event.
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    Or
    You could have just a variable in the view code behind and use messenger to tell that when the value changes from the viewmodel:
    http://social.technet.microsoft.com/wiki/contents/articles/26070.communicating-between-classes.aspx
    Please don't forget to upvote posts which you like and mark those which answer your question.
    My latest Technet article - Dynamic XAML

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    The tree control can handle several events that you can rely on to handle user interaction. I suggest you take a llok at treeevent.prj example that comes with CVI. In your situation, one possible event to handle is EVENT_SELECTION_CHANGE, that marks the operation the user does when clicking on a new tree item.
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    My contributions to the Developer Zone Community
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  • How to Handle Events for JOptionPane buttons?

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