TY_BCS_A_JAVA_SLIP16

SLIP 16:

Create an application to store city names and their STD codes using an appropriate collection. The GUI should allow the following operations:

a. add a new city and its code(No Duplicate)

b. remove a city name and display the code.

c. search for a city name and display the code.

/* Slip16_2 */

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import java.util.*;

class Slip16_2 extends JFrame implements ActionListener

{          

            JTextField t1,t2,t3;

            JButton b1,b2,b3;

            JTextArea t;

            JPanel p1,p2;

            Hashtable ts;

            Slip16_2()

            {

                        ts=new Hashtable();

                        t1=new JTextField(10);

                        t2=new JTextField(10);

                        t3=new JTextField(10);

                        b1=new JButton("Add");

                        b2=new JButton("Search");

                        b3=new JButton("Remove");

                        t=new JTextArea(20,20);

                        p1=new JPanel();

                        p1.add(t);

                        p2= new JPanel();

                        p2.setLayout(new GridLayout(2,3));

                        p2.add(t1);

                        p2.add(t2);

                        p2.add(b1);

                        p2.add(t3);

                        p2.add(b2);

                        p2.add(b3);

                        add(p1);

                        add(p2);

                        b1.addActionListener(this);

                        b2.addActionListener(this);

                        b3.addActionListener(this);

                        setLayout(new FlowLayout());

                        setSize(500,500);

                        setVisible(true);

                        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            }

            public void actionPerformed(ActionEvent e)

            {

                        if(b1==e.getSource())

                        {

                                    String name = t1.getText();

                                    int code = Integer.parseInt(t2.getText());

                                    ts.put(name,code);

                                    Enumeration k=ts.keys();

                                    Enumeration v=ts.elements();

                                    String msg="";

                                    while(k.hasMoreElements())

                                    {

                                                msg=msg+k.nextElement()+" = "+v.nextElement()+"\n";

                                    }

                                    t.setText(msg);

                                    t1.setText("");

                                    t2.setText("");

                        }

                        else if(b2==e.getSource())

                        {

                                    String name = t3.getText();

                                    if(ts.containsKey(name))

                                    {

                                                t.setText(ts.get(name).toString());

                                    }

                                    else

                                                JOptionPane.showMessageDialog(null,"City not found ...");

                        }

                        else if(b3==e.getSource())

                        {

                                    String name = t3.getText();

                                    if(ts.containsKey(name))

                                    {

                                                ts.remove(name);

                                                JOptionPane.showMessageDialog(null,"City Deleted ...");

                                    }

                                    else

                                                JOptionPane.showMessageDialog(null,"City not found ...");

                        }

            }

            public static void main(String a[])

            {

                        new Slip16_2();

            }

}