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Numbers 1.0
Complete Source
Code
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.Arrays;
public class Numbers {
private static JFrame myFrame;
private static JPanel myPanel;
private static MenuListener menuListener;
private static FieldListener fieldListener;
private static JMenuBar menuBar;
private static JMenu file, methods, help;
private static JMenuItem exit, aboutNumbers, aboutCollatz;
private static JMenuItem[] methodItem;
private static JLabel titleLabel, questionLabel, answerLabel, copyright;
private static JTextField inputField;
private static JButton enter;
private static JTextArea outputArea;
private static JScrollPane scrollPane;
private static int method;
private static String[] title;
private static String message1, message2;
public static class MenuListener implements
ActionListener {
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (source == exit) System.exit(0);
if (source == aboutNumbers) JOptionPane.showMessageDialog(myPanel,
message1);
if (source == aboutCollatz) JOptionPane.showMessageDialog(myPanel,
message2);
for (int i = 0; i < 7; i++) if (source == methodItem[i]) method = i;
titleLabel.setText(title[method]);
inputField.setText(null);
outputArea.setText(null);
}
}
public static class FieldListener implements
ActionListener {
public void actionPerformed(ActionEvent e) {
int N;
outputArea.setText(null);
try {
N = Integer.parseInt(inputField.getText());
if (N < 1) {
inputField.setText("Invalid Entry!");
N = 0;
}
}
catch (NumberFormatException exp) {
inputField.setText("Invalid Entry!");
N = 0;
}
if (method == 0 && N > 0) {
if (isPrime(N)) outputArea.setText(N + " is a prime number.");
if (!isPrime(N)) outputArea.setText(N + " is NOT a prime number.");
}
if (method == 1 && N > 0) {
String str = Arrays.toString(divisors(N));
outputArea.setText(str.substring(1,str.length()-1));
}
if (method == 2 && N > 0) outputArea.setText(summation(N) + "");
if (method == 3 && N > 0) outputArea.setText(sumDigits(N) + "");
if (method == 4 && N > 0) outputArea.setText(reverseDigits(N) + "");
if (method == 5 && N > 0) outputArea.setText(NthPrime(N) + "");
if (method == 6 && N > 0) {
int[] list = collatz(N);
String str = Arrays.toString(list);
outputArea.setText(str.substring(1,str.length()-1));
outputArea.append("\n\nThere are " + list.length + " terms in this
sequence.");
}
}
}
public static boolean isPrime(int N) {
int n, m, r;
if (N < 2) return false;
if (N == 2) return true;
if (N > 2 && N % 2 == 0) return false;
if (N > 2 && N % 2 != 0) {
n = 2;
m = 3;
r = 1;
while (m <= Math.sqrt(N) && r > 0) {
r = N % m;
m = 2*n + 1;
n++;
}
if (r > 0) return true;
else return false;
}
return false;
}
public static int[] divisors(int N) {
int[] list = new int[(int)N/2];
int divisorCount = 0;
for (int i = 1; i <= N/2; i++) {
if (N % i == 0) {
list[divisorCount] = i;
divisorCount++;
}
}
int[] copy = new int[divisorCount+1];
for (int i = 0; i < divisorCount; i++) copy[i] = list[i];
copy[divisorCount] = N;
return copy;
}
public static int summation(int N) {
int sum = 0;
for (int i = 1; i <= N; i++) sum += i;
return sum;
}
public static int sumDigits(int N) {
int sum = 0;
while (N != 0) {
sum += N % 10;
N /= 10;
}
return sum;
}
public static int reverseDigits(int N) {
int digit, revN;
revN = 0;
if (N < 10) revN = N;
else {
do {
digit = N % 10;
revN = 10*(revN + digit);
N /= 10;
} while (N >= 10);
revN += N;
}
return revN;
}
public static int NthPrime(int N) {
int n, count;
n = 1;
count = 0;
do {
n++;
if (isPrime(n)) count++;
} while (count < N);
return n;
}
public static int[] collatz(int N) {
int[] list = new int[1000];
int terms = 1;
list[0] = N;
while (N != 1) {
if (N % 2 == 0) N /= 2;
else N = 3*N + 1;
list[terms] = N;
terms++;
}
int[] copy = new int[terms];
for (int i = 0; i < terms; i++) copy[i] = list[i];
return copy;
}
public static void main(String[] args) {
myFrame = new JFrame("Numbers 1.0");
myPanel = new JPanel();
menuListener = new MenuListener();
fieldListener = new FieldListener();
menuBar = new JMenuBar();
file = new JMenu("File");
methods = new JMenu("Methods");
help = new JMenu("Help");
exit = new JMenuItem("Exit");
aboutNumbers = new JMenuItem("About Numbers");
aboutCollatz = new JMenuItem("About 3N + 1");
methodItem = new JMenuItem[7];
titleLabel = new JLabel("Prime Number Test");
questionLabel = new JLabel("Enter a positive integer : ");
answerLabel = new JLabel("Answer : ");
copyright = new JLabel("\u00A9 2011 by Dilip Muthukrishnan", JLabel.CENTER);
inputField = new JTextField();
enter = new JButton("Enter");
outputArea = new JTextArea();
scrollPane = new JScrollPane(outputArea);
method = 0;
title = new String[7];
message1 = "This program was written using the Java programming language.
It integrates a\n" +
"list of computational methods that I wrote back in February into a
Graphical\n" +
"User Interface (GUI). The only new technique that I have used in this
program\n" +
"is the try...catch statement for exception handling.";
message2 = "The 3N + 1 sequence of a given natural number N is obtained as
follows. Starting\n" +
"with N, if N is even, divide by 2. If N is odd, compute 3N + 1. Set one
of\n" +
"these results as the new value of N and repeat this process until N = 1.
The\n" +
"unproven Collatz Conjecture in Mathematics states that the 3N + 1
sequence\n" +
"of any natural number ALWAYS terminates at 1 after only a finite number
of steps.";
title[0] = "Prime Number Test";
title[1] = "Divisors";
title[2] = "Summation (1 to N)";
title[3] = "Sum of Digits";
title[4] = "Reverse Digits";
title[5] = "Nth Prime";
title[6] = "3N + 1 Sequence";
myPanel.setLayout(null);
myPanel.setBackground(new Color(255,225,0));
myPanel.add(titleLabel);
myPanel.add(questionLabel);
myPanel.add(answerLabel);
myPanel.add(copyright);
myPanel.add(inputField);
myPanel.add(enter);
myPanel.add(scrollPane);
titleLabel.setBounds(10,10,300,25);
titleLabel.setFont(new Font("TimesRoman",Font.BOLD,18));
questionLabel.setBounds(10,60,150,20);
inputField.setBounds(165,60,100,25);
inputField.setMargin(new Insets(0,5,0,0));
inputField.addActionListener(fieldListener);
enter.addActionListener(fieldListener);
enter.setBounds(275,60,73,25);
enter.setMargin(new Insets(0,0,0,0));
answerLabel.setBounds(10,100,60,20);
scrollPane.setBounds(75,100,275,125);
outputArea.setMargin(new Insets(5,5,5,5));
outputArea.setLineWrap(true);
for (int i = 0; i < 7; i++) {
methodItem[i] = new JMenuItem(title[i]);
methodItem[i].addActionListener(menuListener);
methods.add(methodItem[i]);
}
exit.addActionListener(menuListener);
aboutNumbers.addActionListener(menuListener);
aboutCollatz.addActionListener(menuListener);
file.add(exit);
help.add(aboutNumbers);
help.add(aboutCollatz);
menuBar.add(file);
menuBar.add(methods);
menuBar.add(help);
copyright.setForeground(new Color(0,0,150));
copyright.setBounds(80,260,220,30);
myFrame.setJMenuBar(menuBar);
myFrame.setContentPane(myPanel);
myFrame.setLocation(100,100);
myFrame.setSize(400,350);
myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
myFrame.setResizable(false);
myFrame.setVisible(true);
}
} |