Sharing Community - Java

JavaOne + Develope (no replies)

admin — Tue, 08 Jun 2010 02:07:45 -0600

JavaOne + Develope (September 19 - 23, 2010 San Francisco)

Java Developer Conference

Java Applet (no replies)

admin — Tue, 24 Feb 2009 14:25:12 -0700


/* This program is to determine if a given 3 lengths can form a triangle or not


	It's a Java Applet program where you can put it on a web simply by applying


	the class in the same directory as your index.html and put this code on it


	


	


	JApplet is very similar to GUI


	


*/	





import java.awt.*;


import java.awt.event.*;


import javax.swing.*;





/* Here instead of extends JFrame we would extends JApplet


	Notice when we decleare in JApplet we don't put the " J "


	Like we did in JFrame. Also we don't need the setSize,


	setVisible, and setDefaultCloseOperation.


	


*/





public class Triangle extends JApplet implements ActionListener


{


	private Panel panel;


	private Panel panel2;


	private Panel panel3;


	private Label messageLabel;


	private Label messageLabel2;


	private Label messageLabel3;


	private TextField text1;


	private TextField text2;


	private TextField text3;


	private Button button;


	private Button button1;


	public static int SCROLLBARS_BOTH;





	public void init()


	{





		setLayout(new GridLayout(2,3));


		


		messageLabel = new Label("a");


		text1 = new TextField(10);


		


		messageLabel2 = new Label("b");


		text2 = new TextField(10);


		


		messageLabel3 = new Label("c");


		text3 = new TextField(10);


		


		messageLabel.setBackground(Color.yellow);


		messageLabel.setForeground(Color.blue);


		button = new Button("Clear");


		button.addActionListener(this);


		button.setActionCommand("Clear");


		button1 = new Button("Finish");


		button1.addActionListener(this);


		button1.setActionCommand("Finish");


		


		panel = new Panel();


		panel2 = new Panel();


		panel3 = new Panel();


		


		panel.add(messageLabel);


		panel2.add(messageLabel2);


		panel3.add(messageLabel3);


		


		panel.add(text1);


		panel2.add(text2);


		panel3.add(text3);


		


		/* This sets a textarea, it will appear on the bottom right


			We set the textarea editable to be false so user can not change the text area


			


		*/


		


		TextArea textarea = new TextArea("This program is to determine \nif the given 3 lengths\n" +


													"can form a triangle or not" ,20, 30, SCROLLBARS_BOTH);


		textarea.setEditable(false);


		


		add(panel);


		add(panel2);


		add(panel3);


		add(button);


		add(button1);


		add(textarea);


		


	}


	/* This creates two events for the buttons


		One is for clear and the other even is for enter


		When the user clicks on clear it will reset the text area


		When the user clicks on enter it will tell them the answer


		


	*/


	


		public void actionPerformed(ActionEvent e)


		{


			String s = e.getActionCommand();


			if(s.equals("Clear"))


			{


				text1.setText("");


				text2.setText("");


				text3.setText("");


			}


			if(s.equals("Finish"))


			{





					String L1, L2, L3;


					double length1, length2, length3,sum,sum1;


					double sum2;


			/* We have a handling exception if the user enters nothing


				it will catches the exception and does nothing


				


			*/


					


				try{


						String title = "Triangle";


						L1 = text1.getText();


						L2 = text2.getText();


						L3 = text3.getText();


						length1 = Double.parseDouble(L1);


						length2 = Double.parseDouble(L2);


						length3 = Double.parseDouble(L3);


						sum = length1 + length2;


						sum1 = length1 + length3;


						sum2 = length2 + length3;


					 


						if(sum>length3)


						{


							if((sum1 > length2) && (sum2 > length1))


							{


							


								JOptionPane.showMessageDialog(null,"yes those length can create a triangle");


							}


						}


						else


				


						JOptionPane.showMessageDialog(null,"no, it is not possible to create a triangle with the given length");


					}


					catch(NumberFormatException ae)


					{


					}


			}


		


	}


}

Simple Recursion Program (no replies)

jj — Fri, 06 Feb 2009 13:56:24 -0700

import java.util.*;

public class RecurivePower
{
public static void main(String[] args)
{
int x, n;

Scanner key = new Scanner(System.in);

System.out.println("Enter a number: ");
x = key.nextInt();

System.out.println("Entere the power: ");
n = key.nextInt();

System.out.println("The square root of " + x + " is " + rpower(x, n));// passing x and n

}

static int rpower(int y, int m)
{
if (m==0) return 1; // base case
else return y*rpower(y, m-1);//recursive case
}
}

output:

Enter a number:
2
Entere the power:
2
The square root of 2 is 4

GUI Draw Program (no replies)

admin — Wed, 04 Feb 2009 13:50:04 -0700

// version 1 = version 0 + some drawing

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionAdapter;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.Icon;
import javax.swing.JColorChooser;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JToolBar;
import javax.swing.SwingConstants;
import javax.swing.border.BevelBorder;
/**
  *  The draw application.
  */
public class Draw extends JFrame {
   /**
     * The easel for this application.
     */
	  
	  public static void main(String[] args) { 
      Draw draw = new Draw() ; 
      draw.setSize(300,375) ; 
      draw.setLocation(500,500) ; 
      draw.setVisible(true) ;
		 
   }
   DrawPanel2 drawPanel ;
	
	
   public Draw() { 
      super("Draw") ; 
      // create menubar
		
		this.addWindowListener(new WindowAdapter()
		{
			public void windowclosing(WindowEvent e) 
			{
				System.exit(0);
			}
		});
		
		Container contentPane = this.getContentPane();
		
		contentPane.setLayout(new BorderLayout());
		
		drawPanel = new DrawPanel2();
		drawPanel.setBorder(new BevelBorder(BevelBorder.LOWERED));
		drawPanel.setBackground(Color.white);
		contentPane.add(drawPanel, BorderLayout.CENTER);
		
		JMenuBar menubar = new JMenuBar();
		this.setJMenuBar(menubar);
	
		JMenu filemenu = new JMenu("File");
		JMenu colormenu = new JMenu("Color");
		menubar.add(filemenu);
		menubar.add(colormenu);
		
		Action clear = new ClearAction();
		Action quit = new QuitAction();
		Action select = new SelectColorAction();

		
		filemenu.add(clear);
		filemenu.add(quit);
		colormenu.add(select);

		
      // create toolbar 
		JToolBar toolbar = new JToolBar();
		toolbar.add(clear);
		toolbar.add(select);
		toolbar.add(quit);
		contentPane.add(toolbar, BorderLayout.NORTH);
		
		JToolBar colors = new JToolBar();
		colors.setOrientation(SwingConstants.VERTICAL);
		contentPane.add(colors, BorderLayout.WEST);   

   }
    

	class ClearAction extends AbstractAction
	{
		public ClearAction()
	{
		super("Clear");
		}
		public void actionPerformed(ActionEvent e)
		{
			drawPanel.clear();
		}
	}

class QuitAction extends AbstractAction
{
	public QuitAction()
	{
		super("Quit");
	}
	public void actionPerformed(ActionEvent e)
	{
		int response = JOptionPane.showConfirmDialog(Draw.this, "Do you Really want to Quit?");
		
		if(response == JOptionPane.YES_OPTION)
			System.exit(0);
	}
}

	class ColorAction extends AbstractAction
	{
		Color color;
		
		public ColorAction(Color color)
		{
			this.color = color;
			putValue(Action.SMALL_ICON, new ColorIcon(color));

		}
		
		public void actionPerformed(ActionEvent e)
		{
			drawPanel.setColor(color);
		}
	}
	
	static class ColorIcon implements Icon {
    Color color;

    public ColorIcon(Color color) {
      this.color = color;
    }

    // These two methods specify the size of the icon
    public int getIconHeight() {
      return 16;
    }

    public int getIconWidth() {
      return 16;
    }

    // This method draws the icon
    public void paintIcon(Component c, Graphics g, int x, int y) {
      g.setColor(color);
      g.fillRect(x, y, 16, 16);
    }
  }
	class SelectColorAction extends AbstractAction
	{
		public SelectColorAction(){
		super("Select Color");
		}
		
		public void actionPerformed(ActionEvent e)
		{
			Color color = JColorChooser.showDialog(Draw.this, 
			"Select Drawing Color", drawPanel.getColor());
			if(color!=null)
			drawPanel.setColor(color);
		}
	}
}


//////////////////////////////////////////////////
/**
  *  The  drawing panel.
  */
class DrawPanel2 extends JPanel {
  public DrawPanel2() {
 
    setPreferredSize(new Dimension(450, 200));

   
    addMouseListener(new MouseAdapter() {
      public void mousePressed(MouseEvent e) {
        moveto(e.getX(), e.getY()); // Move to click position
        requestFocus(); // Take keyboard focus
      }
    });


    addMouseMotionListener(new MouseMotionAdapter() {
      public void mouseDragged(MouseEvent e) {
        lineto(e.getX(), e.getY()); 
      }
    });


  }
  protected int last_x, last_y;

  
  public void moveto(int x, int y) {
    last_x = x;
    last_y = y;
  }

  
  public void lineto(int x, int y) {
    Graphics g = getGraphics();
    g.setColor(color); 
    g.drawLine(last_x, last_y, x, y); 
    moveto(x, y);
  }

  
  public void clear() {
    repaint();
  }

  Color color = Color.black;

  public void setColor(Color color) {
    this.color = color;
  }

  public Color getColor() {
    return color;
  }

}

simple program how to append files:)-D:)-D (no replies)

admin — Wed, 04 Feb 2009 00:15:29 -0700

//needed to create an empty text called bday.txt
//


import javax.swing.*;
import java.io.*;

public class Bday
{
	public static void main(String[] args)throws IOException
	{
		
		try
		{
				FileWriter fw = new FileWriter("bday.txt", true);
				PrintWriter pw = new PrintWriter(fw);
				
				String name = JOptionPane.showInputDialog("Enter the person's name");
				name = name.toLowerCase();
				
				pw.println(name);
				
				String bday = JOptionPane.showInputDialog("Enter the person's bday as 1311986");
				
				pw.println(bday);
				
				pw.close();
				
				
			
		}
		catch (NullPointerException e)
		{
		}
			
	}
}

GUI simple color push buttons (1 reply)

admin — Sat, 31 Jan 2009 00:12:01 -0700

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

/**
 	A simple push button GUI
  */
public class PushButton 
          extends JComponent {

   /**
     *  The state of this PushButton.
     */ 
   private boolean state ; 

   /**
     *  The text associated with this PushButton.
     */
   private String text ; 

   /**
     *  Command string associated with this?
     */
   private String actionCommand ; 

   /**
     *  The ActionListeners associated with this PushButton
     */
   protected ActionListener listeners  ;

   /**
     *  Construct from text.
     */
   public PushButton(String txt) {
      this.text = txt ; 
      this.state = false ; 
      this.addMouseListener(new MouseAdapter() {
         public void mousePressed(MouseEvent e) {
            if (state) state = false ;
            else state = true ;
            repaint() ;
            /////////////////////// generate ActionEvent
            if (listeners != null)
               listeners.actionPerformed(
                  new ActionEvent(PushButton.this,
                                  e.getID() ,
                                  PushButton.this.getActionCommand())) ;
         }
      }) ;
   }

   /*** Set the action command. */
   public void setActionCommand(String ac) { 
      this.actionCommand = ac ; 
   }

   /*** Get the action command. */
   public String getActionCommand() { 
      return actionCommand ; 
   }

   /*** Add an action listener to this PushButton. */
   public void addActionListener(ActionListener l) {
      listeners = AWTEventMulticaster.add(listeners,l) ;
   }

   /*** Remove an action listener from this PushButton. */
   public void removeActionListener(ActionListener l) {
      listeners = AWTEventMulticaster.remove(listeners,l) ;
   }

   /*** Return the text on this PushButton. */
   public String getText() { 
      return this.text ; 
   }

   /*** Set the text on this PushButton. */
   public void setText(String txt) { 
      this.text = txt ; 
   }

   /**
     *  Inquire about the state of this PushButton.
     */
   public boolean getSelected() { 
      return this.state ; 
   }

   /** 
     * What dimension does the text have?
     */
   protected Dimension getTextBounds(Graphics g) { 
      g.setFont(this.getFont()) ; 
      FontMetrics fm = g.getFontMetrics(this.getFont()) ;
      int w = fm.stringWidth(this.text), 
          h = fm.getHeight() ;   
      return new Dimension(w,h) ; 
   }



   public Dimension getPreferredSize() {  // ?
      FontMetrics fm = getFontMetrics(getFont());
		return new Dimension(fm.stringWidth(text)+30, fm.getAscent() + fm.getDescent() + 30);
		   
   }

   public Dimension getMinimumSize() { // ?
      return this.getPreferredSize() ; 
   }

   public Dimension getMaximumSize() { // ?
      return this.getPreferredSize() ; 
   }



   /**
     *  Paint the PushButton, depending upon state.
     */
   public void paintComponent(Graphics g) {
      if (!state) paintUp(g) ; 
      else paintDown(g) ;
   }

   public void paintUp(Graphics g) {
      Dimension d = this.getSize() ;
		int width, height;
		int x,y;
      int w = d.width - 1 ;
      int h = d.height - 1 ;
		Font F = g.getFont();
		FontMetrics fm = g.getFontMetrics(F);
		width = fm.stringWidth("Color");
		height = fm.getAscent();
		
		x= getSize().width/2 - width/2;
		
		y = getSize().height / 2 + height / 2;
      g.setColor(Color.blue) ;
      g.drawLine(0,0,w-1,0) ;
      g.drawLine(0,1,0,h-1) ;
      g.setColor(Color.blue) ;
      g.drawLine(1,h-1,w-1,h-1) ;
      g.drawLine(w-1,1,w-1,h-2) ;
      g.setColor(Color.blue) ;
      g.drawLine(1,h,w,h) ;
      g.drawLine(w,1,w,h-1) ;  
      g.setColor(this.getForeground()) ;
		g.drawString(this.getText(), x, y);  
      g.dispose() ;
   }

   public void paintDown(Graphics g) {
      Dimension d = this.getSize() ;
      int w = d.width - 1 ;
      int h = d.height - 1 ;
		int width, height;
		int x,y;
		Font F = g.getFont();
		FontMetrics fm = g.getFontMetrics(F);
		width = fm.stringWidth("Red");
		height = fm.getAscent();
		
		x= getSize().width/2 - width/2;
		
		y = getSize().height / 2 + height / 2;
      g.setColor(this.getBackground()) ;  /// background color
      g.fillRect(0,0,w,h) ; 
      g.setColor(Color.white) ;
      g.drawLine(0,0,0,h-1) ;
      g.drawLine(1,0,w-1,0) ;
      g.setColor(Color.blue);
      g.drawLine(1,1,1,h-2) ;
      g.drawLine(1,1,w-2,1) ;
      g.setColor(Color.lightGray) ;
      g.drawLine(2,h-1,2,h-1) ;  // just one square
      g.drawLine(w-1,1,w-1,1) ;
      g.setColor(Color.white) ;
      g.drawLine(0,h,w,h) ;
      g.drawLine(w,0,w,h-1) ;
		g.drawString(this.getText(), x, y);
      g.dispose() ;
   }

   /**
     * Test stub, from command line. 
     */
   public static void main(String[] args) { 
      PBtest pbt = new PBtest() ; 
      pbt.setSize(300,375) ; 
      pbt.setLocation(500,500) ; 
      pbt.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE) ; 
      pbt.setVisible(true) ; 
   }


}  // end of PushButton class

/////////////////////////////////// test user 

/**
  *    Set up three PushButtons to control color of a panel.
  */
class PBtest extends JFrame 
            implements ActionListener {
      
   JPanel midpane ; 
   PushButton pb1, pb2, pb3 ; 

   public PBtest() { 
      super.setTitle("PushButton Test (R/G/B)") ; 
      midpane = new JPanel() ; 
      JToolBar toolbar = new JToolBar() ;
      pb1 = 
         new PushButton("Red") ; 
      ///// REMOVE later
      pb1.setPreferredSize(new Dimension(30,30)) ; 
      /////
      pb1.setActionCommand("red") ; 
      pb1.addActionListener(this) ; 
		pb1.setBackground(Color.red);
      pb1.setForeground(Color.red) ;
		pb1.setFont(new Font("Serif", Font.ITALIC, 40)); 
      pb2 = 
         new PushButton("Green") ;
      pb2.addActionListener(this) ; 
      pb2.setActionCommand("green") ;
		pb2.setBackground(Color.green);
      pb2.setForeground(Color.green) ;
		pb2.setFont(new Font("MONOSPACED", Font.PLAIN, 20)); 
      pb3 = 
         new PushButton("Blue") ;
      pb3.addActionListener(this) ; 
      pb3.setActionCommand("blue") ; 
      pb3.setBackground(Color.blue) ;
		pb3.setForeground(Color.blue);
		pb3.setFont(new Font("Serif", Font.BOLD, 10)); 
      toolbar.add(pb1) ; 
      toolbar.add(new JToolBar.Separator()) ;   
      toolbar.add(pb2) ; 
      toolbar.add(new JToolBar.Separator()) ;   
      toolbar.add(pb3) ; 
      this.getContentPane().setLayout(new BorderLayout()) ; 
      this.getContentPane().add(toolbar, BorderLayout.NORTH) ; 
      this.getContentPane().add(midpane, BorderLayout.CENTER) ; 
      this.setVisible(true) ; 
      this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE) ;
   }
   public void actionPerformed(ActionEvent a) {  
      int r = (pb1.getSelected() ? 255 : 0), 
          g = (pb2.getSelected() ? 255 : 0),
          b = (pb3.getSelected() ? 255 : 0) ;
      midpane.setBackground(new Color(r,g,b)) ; 
      midpane.repaint() ; 
   }

}

>:D
admin — Sun, 25 Jan 2009 16:47:15 -0700
[www.syncedit.com]

A free software JavaLauncher, it can convert your .class file into an application file where you can use it on other computers.

Guess Random number game java (no replies)

admin — Fri, 23 Jan 2009 16:41:32 -0700

import java.util.Scanner;
import javax.swing.JOptionPane;
import java.util.Random;

public class RadnomNumber
{
	public static void main(String[] args)
	{
		int n = 0;
		int guess;
		Scanner key = new Scanner(System.in);
		Random randomNumbers = new Random();
		
		int secret = randomNumbers.nextInt(100);
		
		JOptionPane.showMessageDialog(null, "A secret number between 1-100 generated...");
		
		
		do
		{
			String input = JOptionPane.showInputDialog("Enter your guess? ");
			guess = Integer.parseInt(input);
			
			if (secret == guess)
			{
				JOptionPane.showMessageDialog(null,"Correct in " + n + 1 + " guessess.\n");
				break;
			}
			else if (guess == 0)
			{
				JOptionPane.showMessageDialog(null, "The secret number is " + secret +".\n");
			}
			else if(secret < guess)
			{
				JOptionPane.showMessageDialog(null,"Guess is too high...");
			}
			else if(secret > guess)
			{
				JOptionPane.showMessageDialog(null,"Guess is too low...");
			}
			
				n++;
			}while((n<8) && (guess!=0));
			if(n==8)
			{
					JOptionPane.showMessageDialog(null,"Too many guesses, the secret number is " + secret);
			}
		}
	}

Simple GUI (1 reply)

admin — Mon, 12 Jan 2009 10:46:32 -0700

// The purpose of this program is to have people to compete with friends
// see how fast they can do multiplication, and addition
//

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.Date;
import java.util.Random;
import java.io.*;

//Creates a window
//

public class Calculator extends JFrame
{
private final int WINDOW_WIDTH = 800;
private final int WINDOW_HEIGHT = 400;
private JPanel panel;
private JLabel messagelabel;
private JTextField TextFile;

//This is the function for multiplication
//If the user clicks on multiplication
//This function will be activated
//
public void Multiplication()
{
Date d1 = new Date();//needed to keep track of time
int x, y, sum;
int n = 0;
int userAnswer;
String input;

Random randomNumbers = new Random();//declares randomNumbers as random

x = randomNumbers.nextInt(9);//x holds random number between 0 and 9
y = randomNumbers.nextInt(9);//y holds random number between 0 and 9

//A forloop that will terminated after 30 seconds
//JOptionPane is used here to interact with the user
//It will show the user what are they trying to add
//It asks the user to enter an answer
//Then shows them another equation after they've entered the answer
//

for (int seconds = 0; seconds <= 30; seconds++)
{
x = randomNumbers.nextInt(9);
y = randomNumbers.nextInt(9);

input = JOptionPane.showInputDialog(x + "x" + y + "=");

sum = x * y;

userAnswer = Integer.parseInt(input);//Turn the user input into an integer

//Determines if the user's answer is correct or not
//If the user's answer is correct we increment n
//If the user's answer is incorrect we decrement n
//

if ( userAnswer == sum)
{
n++;
}

else
{
n--;
}

}
//keep tracks of time
//
Date d2 = new Date();
long elapsed_time = d2.getTime() - d1.getTime();

//Determines if the user beat the high score or not
//

if ( n >= 28 && elapsed_time < 40000)
{
JOptionPane.showMessageDialog(null, "Good job you beat the high score");
}
else
{
JOptionPane.showMessageDialog(null, "you did not beat the high score & your score is " + n + "& time is " + elapsed_time);
}

System.exit(0);
}

//This is the addition method
//This method will be call if the user click on addition
//All the fuction is the same as the multiplication
//So you can go back and look at the multiplication
//
public void Addition()
{
Date d1 = new Date();
int x, y, sum;
int n = 0;
int userAnswer;
String input;

Random randomNumbers = new Random();

x = randomNumbers.nextInt(20);
y = randomNumbers.nextInt(20);

for (int seconds = 0; seconds <= 30; seconds++)
{
x = randomNumbers.nextInt(20);
y = randomNumbers.nextInt(20);

input = JOptionPane.showInputDialog(x +"+" + y + "=");

sum = x + y;

userAnswer = Integer.parseInt(input);

if ( userAnswer == sum)
{
n++;
}

else
{
n--;
}

}

Date d2 = new Date();
long elapsed_time = d2.getTime() - d1.getTime();

if ( n >= 28 && elapsed_time < 40000)
{
JOptionPane.showMessageDialog(null, "Good job you beat JJ's high score");
}
else
{
JOptionPane.showMessageDialog(null, "you did not beat the high score & your score is " + n + "& time is " + elapsed_time);
}

System.exit(0);
}

//This is the calculator panel
//We will add this to the window
//

public Calculator()
{

setTitle("JJ's Math Game");//Sets the title for the window

setSize(WINDOW_WIDTH, WINDOW_HEIGHT);//Sets the size of the window

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//Determines what will happen if the user click on X
setLayout(new GridLayout(1,1));//The layout of the window

JButton button1 = new JButton ("Multiplication");//Creates button1
//It will be display as Multiplication

JButton button2 = new JButton("Addition");//Creates button2
//It will be display as Addition

button1.addActionListener(new Button1Listener());//Adds button1 so when user click something will happen
button2.addActionListener(new Button2Listener());//Adds button2 so when user click something will happen

add(button1);//Adds button1 to the window
add(button2);//Adds button2 to the window

setVisible(true);//Set the Window visible
}

//This is the implementation for Multiplication
//It determines what will happen if the user click on something
//

class Button1Listener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String actionCommand = e.getActionCommand();//e.getActionCommand is a built in fuction from java

//If the user clicks on Multiplication
//The method Multiplication will be call
//Then it will be display
//
if (actionCommand.equals("Multiplication"))
{
Multiplication();
}

}
}

//This is the implementation for Addition
//It determines what will happen if the user click on something
//

public class Button2Listener implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String actionCommand1 = e.getActionCommand();

//If the user clicks on Addition
//The method Addition will be call
//Then it will be display
//
if (actionCommand1.equals("Addition"))
{
Addition();
}
}
}

//This is the main method
//
public static void main(String[] args)
{

new Calculator();//Instant window for Calculator
}
}

generates Random name (2 replies)

admin — Sun, 21 Mar 2010 00:45:40 -0600

//The goal of this program is to generate random Strings

import java.util.Scanner;
import java.io.*;
import java.util.Random;

public class RandomName
{
public static void main(String[] args) throws IOException
{

Scanner key = new Scanner(System.in);
Random randomNumbers = new Random();

int n = 0;
String[] names= new String[50];
int index = 0;

// Asking user to enter a name of a file to read
//

System.out.println("Enter a file name: ");
String fileName = key.nextLine();

//Opens the file from user
//

File file = new File(fileName);
Scanner outputFile = new Scanner(file);

while(outputFile.hasNext())
{
names[index] = outputFile.nextLine();

index++;

n++;
}

// opens a file from user to read
//

System.out.println("Enter a file to write in: ");
String writeFile = key.nextLine();

FileWriter fwriter = new FileWriter(writeFile, true);
PrintWriter pw = new PrintWriter (fwriter);

//prints out the number of people in the file
//Store into an array
//prints out a random name from the file

System.out.println("Number of people: " + n );
int x = randomNumbers.nextInt(50);

System.out.println("\n" + names[x]);
pw.println(names[x]);

System.out.println("what do you want to do ");
String command = key.nextLine();

//contine to loop the program
//Write to the file
//

while(!command.equals("exit"))
{
x = randomNumbers.nextInt(35);
System.out.println("\n" + names[x]);
System.out.println("what do you want to do: ");
command = key.nextLine();
pw.println(names[x]);
}

pw.close();
outputFile.close();

//Exit the program if user enter exit
//

if(command.equals("exit"))
{
System.exit(0);
}
}

}

Multiplication Game (no replies)

jj — Mon, 05 Jan 2009 11:34:52 -0700

import javax.swing.JOptionPane;
import java.util.Date;
import java.util.Random;

public class RandomGame
{
public static void main(String[] args)
{
random();
}
public static void random()
{
Date d1 = new Date();
int x, y, sum;
int n = 0;
int userAnswer;
String input;

Random randomNumbers = new Random();

x = randomNumbers.nextInt(9);
y = randomNumbers.nextInt(9);

for (int seconds = 0; seconds <= 30; seconds++)
{
x = randomNumbers.nextInt(9);
y = randomNumbers.nextInt(9);

input = JOptionPane.showInputDialog(x + "x" + y + "=");

sum = x * y;

userAnswer = Integer.parseInt(input);

if ( userAnswer == sum)
{
n++;
}

else
{
n--;
}

}

Date d2 = new Date();
long elapsed_time = d2.getTime() - d1.getTime();

if ( n >= 28 && elapsed_time < 40000)
{
JOptionPane.showMessageDialog(null, "Good job you beat the high score");
}
else
{
JOptionPane.showMessageDialog(null, "srry you did not beat the high score & your score is " + n + "& time is " + elapsed_time);
}

System.exit(0);
}
}

handling Exceptions (no replies)

jj — Mon, 05 Jan 2009 11:31:21 -0700

import java.io.*;
import java.util.*;

public class openFile
{
public static void main(String[] args)throws IOException
{

String fileName;
Scanner key = new Scanner(System.in);

System.out.println("Enter the name of a file: ");
fileName = key.nextLine();

File file = new File(fileName);
Scanner outPut = new Scanner(file);

int even = 0;
int odd = 0;

while(outPut.hasNext())
{
try //
{
int k = outPut.nextInt();

if(k%2==0)
{
even++;
}
else
{
odd++;
}

}

catch (InputMismatchException e)
{
outPut.nextLine();
}

}

System.out.println("even " + even);
System.out.println("odd " + odd);
outPut.close();
}

}