Question

design a windows application (measurement converter) that has two text boxes and tow combo boxes, the user will assign an integer value in the first text box and to be added to the selected unit from the first combo box then the user will choose another unit from the second combo box and the convertered value will be shown on the second text box

the units are :

Kilometer
Meter
Centimeter
Millimeter
Mile
Yard
Foot
Inch
Nautical Mile

(on c#)

Answer 1

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Converter extends JFrame {

    static JFrame frame;
    static JComboBox metb, impb;
    static Container pane;
    static Insets insets;
    static JLabel to;
    static JButton go, clear1, clear2;
    static JTextField metf, impf;
    static Dimension screenSize;
    static Point middle, newLocation;  
    
    public static void compute(String meti, String impi, int x, int y, double ratio) {
        if (meti.length() >= 1 && impi.length() == 0) { //converting from metric to imperial        
            if (metb.getSelectedIndex() != 0 && impb.getSelectedIndex() != 0) { //if user has selected units     
                //length
                if (metb.getSelectedIndex() >= 1 && impb.getSelectedIndex() >= 1) {                   
                    if (metb.getSelectedIndex() == x && impb.getSelectedIndex() == y) { 
                    double parse = Double.parseDouble(meti);
                    double ans = parse * ratio;
                    String result = "" + ans;
                    impf.setText(result);                                      
                    }                                        
                }
            } else {
                JOptionPane.showMessageDialog(frame,"Please select you units");
            }       
        } else if (meti.length() == 0 && impi.length() >= 1) { //converting from imperial to metric  
            if (metb.getSelectedIndex() != 0 && impb.getSelectedIndex() != 0) { //if user has selected units
                if (metb.getSelectedIndex() >= 1 && impb.getSelectedIndex() >= 1) {                   
                    if (metb.getSelectedIndex() == x && impb.getSelectedIndex() == y) { 
                    double parse = Double.parseDouble(impi);
                    double ans = parse / ratio;
                    String result = "" + ans;
                    metf.setText(result);                                      
                    }                                        
                }
            } else {
                JOptionPane.showMessageDialog(frame,"Please select your units");
            }   
        }        
    }
    
    public static void temperature(String meti, String impi) {
        if (meti.length() >= 1 && impi.length() == 0) { //converting from metric to imperial        
            if (metb.getSelectedIndex() != 0 && impb.getSelectedIndex() != 0) { //if user has selected units     
                //length
                if (metb.getSelectedIndex() >= 7 && metb.getSelectedIndex() <= 8) {                   
                    if (metb.getSelectedIndex() == 7 && impb.getSelectedIndex() == 10) {//k f
                        double parse = Double.parseDouble(meti);
                        double ans = 9/5 * (parse - 273) + 32;
                        String result = "" + ans;
                        impf.setText(result);    
                    } else if (metb.getSelectedIndex() == 8 && impb.getSelectedIndex() == 9) {//c k
                        double parse = Double.parseDouble(meti);
                        double ans = parse + 273;
                        String result = "" + ans;
                        impf.setText(result);
                    } else if (metb.getSelectedIndex() == 8 && impb.getSelectedIndex() == 10) {//c f
                        double parse = Double.parseDouble(meti);
                        double ans = 9/5 * parse + 32;
                        String result = "" + ans;
                        impf.setText(result);
                    }                                                      
                }
            } else {
                JOptionPane.showMessageDialog(frame,"Please select your units");
            }       
        } else if (meti.length() == 0 && impi.length() >= 1) { //converting from imperial to metric  
            if (metb.getSelectedIndex() != 0 && impb.getSelectedIndex() != 0) { //if user has selected units
                    if (metb.getSelectedIndex() == 7 && impb.getSelectedIndex() == 10) {//f k
                        double parse = Double.parseDouble(impi);
                        double ans = 9/5 * (parse - 32) + 273;
                        String result = "" + ans;
                        metf.setText(result);    
                    } else if (metb.getSelectedIndex() == 8 && impb.getSelectedIndex() == 9) {//k c
                        double parse = Double.parseDouble(impi);
                        double ans = parse - 273;
                        String result = "" + ans;
                        metf.setText(result);
                    } else if (metb.getSelectedIndex() == 8 && impb.getSelectedIndex() == 10) {//f c
                        double parse = Double.parseDouble(impi);
                        double ans = 9/5 * parse - 32;
                        String result = "" + ans;
                        metf.setText(result);
                    }
            } else {
                JOptionPane.showMessageDialog(frame,"Please select you units");
            }   
        }       
    }        
    
    public static class goAction implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            String meti = metf.getText();
            String impi = impf.getText();
            if (meti.length() == 0 && impi.length() >= 1 || meti.length() >= 1 && impi.length() == 0) {
                compute(meti, impi, 1, 1, 0.0393700787); //mm in
                compute(meti, impi, 1, 2, 0.0032808399); //mm ft
                compute(meti, impi, 1, 3, 0.0010936133);//mm yd
                compute(meti, impi, 1, 4, 0.000000621371192); //mm mi
                compute(meti, impi, 2, 1, 0.393700787);//cm in
                compute(meti, impi, 2, 2, 0.032808399);//cm ft
                compute(meti, impi, 2, 3, 0.010936133);//cm yd
                compute(meti, impi, 2, 4, 0.00000621371192);//cm mi
                compute(meti, impi, 3, 1, 39.3700787);//m in
                compute(meti, impi, 3, 2, 3.2808399);//m ft
                compute(meti, impi, 3, 3, 1.0936133);//m yd
                compute(meti, impi, 3, 4, 0.000621371192);//m mi
                compute(meti, impi, 4, 1, 39370.0787);//km in
                compute(meti, impi, 4, 2, 3280.8399);//km ft
                compute(meti, impi, 4, 3, 1093.6133);//km yd
                compute(meti, impi, 4, 4, 0.621371192);//km mi
                compute(meti, impi, 5, 5, 0.0338140227);//ml fl oz
                compute(meti, impi, 5, 6, 0.00211337642);//ml pt
                compute(meti, impi, 5, 7, 0.00105668821);//ml qt
                compute(meti, impi, 5, 8, 0.000264172052);//ml gal
                compute(meti, impi, 6, 5, 33.8140227);//l fl oz
                compute(meti, impi, 6, 6, 2.11337642);//l pt
                compute(meti, impi, 6, 7, 1.05668821);//l qt
                compute(meti, impi, 6, 8, 0.264172052);//l gal
                compute(meti, impi, 7, 9, 1); //k k   
                compute(meti, impi, 9, 11, 0.0352739619);//g oz
                compute(meti, impi, 9, 12, 0.00220462262);//g lb
                compute(meti, impi, 9, 13, 0.000157473044);//g st
                compute(meti, impi, 9, 14, 0.00000110231131);//g t
                compute(meti, impi, 10, 11, 35.2739619);//kg oz
                compute(meti, impi, 10, 12, 2.20462262);//kg lb
                compute(meti, impi, 10, 13, 0.157473044);//kg st
                compute(meti, impi, 10, 14, 0.00110231131);//kg t
                compute(meti, impi, 11, 11, 35273.9619);//mt oz
                compute(meti, impi, 11, 12, 2204.62262);//mt lb
                compute(meti, impi, 11, 13, 157.473044);//mt st
                compute(meti, impi, 11, 14, 1.10231131);//mt t
                temperature(meti, impi);//k f, c k, c f 
            } else if (meti.length() >= 1 && impi.length() >= 1) { //input in two fields        
                JOptionPane.showMessageDialog(frame,"Please only put a number on one side");
                impf.setText("");
                metf.setText("");             
            } else if (meti.length() == 0 && impi.length() == 0) { //input in no fields        
                JOptionPane.showMessageDialog(frame,"Please enter a number to be converted");            
            }                 
        }
    }       
    
    public static class clear1Action implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            metf.setText("");
        }
    }
    
    public static class clear2Action implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            impf.setText("");
        }
    }
    
    public static void main (String[] args) {
    
        try {UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());}
        catch (ClassNotFoundException e) {}
        catch (InstantiationException e) {}
        catch (IllegalAccessException e) {}
        catch (UnsupportedLookAndFeelException e) {}
    
        String[] metric = { "metric:", "millimetres", "centimetres", "metres", "kilometres", "mililitres", "litres", "kelvin", "celcius", "grams", "kilograms", "tonnes" };                
        String[] imperial = { "imperial:", "inches", "feet", "yards", "miles", "fluid ounces", "US pints", "US quarts", "US gallons", "kelvin", "fahrenheit", "ounces", "pounds", "stones", "tons" };   
        
        frame = new JFrame ("Unit Converter");                        
        metb = new JComboBox (metric);
        impb = new JComboBox (imperial);  
        to = new JLabel("< -- to -- >");
        go = new JButton("Go");
        clear1 = new JButton("C");
        clear2 = new JButton("C");
        metf = new JTextField();
        impf = new JTextField();             
               
        pane = frame.getContentPane();
        insets = pane.getInsets();
        pane.setLayout(null);        
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        metb.setSelectedIndex(0);
        impb.setSelectedIndex(0);
        
        pane.add(metf);
        metf.setBounds(insets.left + 5, insets.top + 5, 200, metf.getPreferredSize().height);       
        
        pane.add(metb);
        metb.setBounds(insets.left + 5, metf.getHeight() + 5, 282, metb.getPreferredSize().height);
        
        pane.add(clear1);
        clear1.setBounds(metf.getX() + metf.getWidth() + 5, insets.top + 5, clear1.getPreferredSize().width, metb.getPreferredSize().height);
        
        pane.add(to);
        to.setBounds(clear1.getX() + clear1.getWidth() + 5, insets.top + 5, to.getPreferredSize().width, to.getPreferredSize().height);
        
        pane.add(impf);
        impf.setBounds(to.getX() + to.getWidth() + 5, insets.top + 5, 200, impf.getPreferredSize().height);  
        
        pane.add(impb);
        impb.setBounds(metb.getX() + metb.getWidth() + 5, impf.getHeight() + 5, 283, impb.getPreferredSize().height);
        
        pane.add(clear2);
        clear2.setBounds(impf.getX() + impf.getWidth() + 5, insets.top + 5, clear2.getPreferredSize().width, metb.getPreferredSize().height);      
        
        pane.add(go);
        go.setBounds(clear2.getX() + clear2.getWidth() + 5, insets.top + 5, go.getPreferredSize().width, metb.getPreferredSize().height);
        
        go.addActionListener(new goAction());
        clear1.addActionListener(new clear1Action());
        clear2.addActionListener(new clear2Action());
        
        frame.setSize(580,110); 
        
        screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        middle = new Point(screenSize.width / 2, screenSize.height / 2);
        newLocation = new Point(middle.x - (frame.getWidth() / 2), middle.y - (frame.getHeight() / 2));
        frame.setLocation(newLocation);
        
        frame.setVisible(true);
    }
}