java date selector ..

hey,,,, i am creating my java project...for that i implementing a car renting system and i had used combo boxes to get Ranting start day inputs..3 combo(sy,sm,sd) yyyy ,mm,dd and for returning day i need to get 3 combo inputs(ry,rm,rd)... so when i update starting day... others should be updated

public class Traval_guider extends javax.swing.JFrame { java.util.Calendar cal= java.util.Calendar.getInstance();

    int day = cal.get(Calendar.DATE);
    int month = cal.get(Calendar.MONTH) + 1;
    int year = cal.get(Calendar.YEAR);

/** Creates new form Traval_guider */
public Traval_guider(String name)   
{
    super("Amizing Destination Traval(pvt) LTD - "+name);
    initComponents();
    jLabel1.setText("Welcome "+name);




    for(int i=year;i<year+5;i++)
    {
                    sy.addItem(i);

    }
    for (int k = month; k < 13; k++)
    {
                    sm.addItem(k);


    }
    for(int j=day;j<32;j++)
    {
                    sd.addItem(j);

    }
    for(int i=(Integer) sy.getSelectedItem();i<(Integer)sy.getSelectedItem()+5;i++)
    {
        ey.addItem(i);
    }


}

//i add same codeings for all 3(sy,sm,sd) action

private void syActionPerformed(java.awt.event.ActionEvent evt) {
ey.removeAllItems(); em.removeAllItems(); ed.removeAllItems(); if((Integer)sy.getSelectedItem()>year) { for(int i=1;i<13;i++) { em.addItem(i); } for (int k = 1; k < 32; k++) { ed.addItem(k);

        }

    }
    else
    {  for (int k =(Integer)sm.getSelectedItem(); k < 13; k++)
        {
                    em.addItem(k);

        }

                if((Integer)sm.getSelectedItem()>month)
                {
                       for(int j=1;j<32;j++)
                     {
                        ed.addItem(j);

                     }
                }
                else
                {
                     for(int j=day+1;j<32;j++)
                    {
                         ed.addItem(j);

                    }
                }
    } // TODO add your handling code here:
}

//and am geting this error please help me Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at st.Travalguider.syActionPerformed(Travalguider.java:237) at st.Travalguider.access$000(Travalguider.java:22) at st.Travalguider$1.actionPerformed(Travalguider.java:137) at javax.swing.JComboBox.fireActionEvent(JComboBox.java:1240) at javax.swing.JComboBox.contentsChanged(JComboBox.java:1311) at javax.swing.AbstractListModel.fireContentsChanged(AbstractListModel.java:100) at javax.swing.DefaultComboBoxModel.setSelectedItem(DefaultComboBoxModel.java:88) at javax.swing.DefaultComboBoxModel.addElement(DefaultComboBoxModel.java:126) at javax.swing.JComboBox.addItem(JComboBox.java:696) at st.Travalguider.(Travalguider.java:58) at st.Travalguider$4.run(Travalguider.java:355) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209) at java.awt.EventQueue.dispatchEvent(EventQueue.java:597) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161) at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)

thanks

April 11, 2012 at 3:47 PM

import java.sql.*;
import java.awt.*;
import java.util.*;
import java.text.*;
import javax.swing.*;
import java.awt.event.*;

public class GetDate{
    static String months[]={"Month","Jan","Feb","Mar","App","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"};
    static int getMonth(String month){
    for(int i = 0; i<12; i++) {
      if(month == months[i])
          return i;
    }
    return 0;
    }
public static void main(String args[]){
GetDate get=new GetDate();
}
public GetDate(){
JFrame f = new JFrame();
f.getContentPane().setLayout(null);
final JComboBox day=new JComboBox();
final JComboBox month=new JComboBox();
final JComboBox year=new JComboBox();
JButton button= new JButton("Submit");
day.addItem("Day");
year.addItem("Year");
for(int i=1;i<=31;i++){
day.addItem(i);
}
day.setBounds(10,10,10,10);
for(int j=0;j<months.length;j++){
month.addItem(months[j]);
}
for(int k=1980;k<=2012;k++){
year.addItem(k);
}
day.setBounds(50,50,60,20);
month.setBounds(120,50,80,20);
year.setBounds(210,50,60,20);
button.setBounds(50,80,100,20);
button.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
Object ob1=day.getSelectedItem();
Object ob2=month.getSelectedItem();
Object ob3=year.getSelectedItem();
int d=Integer.parseInt(ob1.toString());
String mon=ob2.toString();
int m=getMonth(mon);
int y=Integer.parseInt(ob3.toString());
Calendar cal = GregorianCalendar.getInstance();
cal.set(y, m-1, d);  
SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
System.out.println(sdf.format(cal.getTime()));
}
});
f.add(day);
f.add(month);
f.add(year);
f.add(button);
f.setVisible(true);
f.setSize(300,200);
}
}

August 27, 2012 at 1:44 AM

please can u help me creating a java code for below one..

1) create form to add event with "Title", "description", "venue", "event start date", "event end date" and number of attendees".

2) use date picker to choose date (event start date should be greaterthat or equals to today's date and and event end date should be greater that start date.

3) list all events in table view, create action for each event to "Apply" and "list attendees" 4) create form to apply for event take attendees deatils like" name, email id, some description". 5) store attendees list in attendee table as per event id. 6) hide apply action after " attendees" count is equals to "n".