COMP16121 Sample Code Lecture 1

Transcription

1 COMP16121 Sample Code Lecture 1 Sean Bechhofer, University of Manchester, Manchester, UK sean.bechhofer@manchester.ac.uk 1 SimpleFrame 1 import javax.swing.jframe; 2 3 public class SimpleFrame { 4 5 /* Main method to drive the program */ 6 public static void main( String [] args ) { 7 JFrame theframe = new JFrame(); 8 theframe.settitle( "A Frame" ); 9 theframe.setsize( 300, 200 ); 10 theframe.setvisible( true ); 11 } // main } // SimpleFrame 1

2 2 HelloWorld 1 import java.awt.container; 2 import javax.swing.jlabel; 3 import javax.swing.jframe; 4 5 public class HelloWorld extends JFrame { 6 7 /* Constructor */ 8 public HelloWorld() { 9 settitle( "Hello World" ); 10 /* Get the contents of the frame and add a label to it */ 11 Container contents = getcontentpane(); 12 contents.add( new JLabel( "Hello World!" ) ); /* Specify appropriate behaviour when the window is closed */ 15 setdefaultcloseoperation( EXIT_ON_CLOSE ); /* pack the frame */ 18 pack(); 19 } // HelloWorld /* Main method to drive the program */ 22 public static void main( String [] args ) { 23 HelloWorld thehelloworld = new HelloWorld(); 24 thehelloworld.setvisible( true ); 25 } // main } // HelloWorld 2

3 3 HelloSolarSystem 1 import java.awt.container; 2 import java.awt.flowlayout; 3 import javax.swing.jlabel; 4 import javax.swing.jframe; 5 6 public class HelloSolarSystem extends JFrame { 7 8 /* Constructor */ 9 public HelloSolarSystem() { 10 settitle( "Hello SolarSystem" ); 11 /* Get the contents of the frame. */ 12 Container contents = getcontentpane(); 13 /* Set the Layout Manager */ 14 contents.setlayout( new FlowLayout( FlowLayout.LEFT, 10, 10 ) ); 15 /* Add labels */ 16 contents.add( new JLabel( "Hello Mercury!" ) ); 17 contents.add( new JLabel( "Hello Venus!" ) ); 18 contents.add( new JLabel( "Hello Earth!" ) ); 19 contents.add( new JLabel( "Hello Mars!" ) ); 20 contents.add( new JLabel( "Hello Jupiter!" ) ); 21 contents.add( new JLabel( "Hello Saturn!" ) ); 22 contents.add( new JLabel( "Hello Uranus!" ) ); 23 contents.add( new JLabel( "Hello Neptune!" ) ); 24 contents.add( new JLabel( "Hello Pluto!" ) ); /* Specify appropriate behaviour when the window is closed */ 27 setdefaultcloseoperation( EXIT_ON_CLOSE ); /* pack the frame */ 30 pack(); 31 } // HelloSolarSystem /* Main method to drive the program */ 34 public static void main( String [] args ) { 35 HelloSolarSystem thehellosolarsystem = 36 new HelloSolarSystem(); 37 thehellosolarsystem.setvisible( true ); 38 } // main } // HelloSolarSystem 3

4 4 HelloSolarSystemGrid 1 import java.awt.container; 2 import java.awt.gridlayout; 3 import javax.swing.jlabel; 4 import javax.swing.jframe; 5 6 public class HelloSolarSystemGrid extends JFrame { 7 8 /* Constructor */ 9 public HelloSolarSystemGrid() { 10 settitle( "Hello SolarSystem" ); 11 /* Get the contents of the frame. */ 12 Container contents = getcontentpane(); 13 /* Set the Layout Manager */ 14 contents.setlayout( new GridLayout( 0, 3, 10, 10 ) ); 15 /* Add labels */ 16 contents.add( new JLabel( "Hello Mercury!" ) ); 17 contents.add( new JLabel( "Hello Venus!" ) ); 18 contents.add( new JLabel( "Hello Earth!" ) ); 19 contents.add( new JLabel( "Hello Mars!" ) ); 20 contents.add( new JLabel( "Hello Jupiter!" ) ); 21 contents.add( new JLabel( "Hello Saturn!" ) ); 22 contents.add( new JLabel( "Hello Uranus!" ) ); 23 contents.add( new JLabel( "Hello Neptune!" ) ); 24 contents.add( new JLabel( "Hello Pluto!" ) ); /* Specify appropriate behaviour when the window is closed */ 27 setdefaultcloseoperation( EXIT_ON_CLOSE ); /* pack the frame */ 30 pack(); 31 } // HelloSolarSystemGrid /* Main method to drive the program */ 34 public static void main( String [] args ) { 35 HelloSolarSystemGrid thehellosolarsystemgrid = 36 new HelloSolarSystemGrid(); 37 thehellosolarsystemgrid.setvisible( true ); 38 } // main } // HelloSolarSystemGrid 4

5 5 HelloSmiley 1 import java.awt.container; 2 3 import javax.swing.imageicon; 4 import javax.swing.jframe; 5 import javax.swing.jlabel; 6 7 public class HelloSmiley extends JFrame { 8 9 /* Constructor */ 10 public HelloSmiley() { 11 settitle( "Hello Smiley" ); 12 /* Get the contents of the frame and add a label to it */ 13 Container contents = getcontentpane(); 14 contents.add( new JLabel( new ImageIcon( "smiley.jpg" ) ) ); /* Specify appropriate behaviour when the window is closed */ 17 setdefaultcloseoperation( EXIT_ON_CLOSE ); /* pack the frame */ 20 pack(); 21 } // HelloWorld /* Main method to drive the program */ 24 public static void main( String [] args ) { 25 HelloSmiley thehellosmiley = new HelloSmiley(); 26 thehellosmiley.setvisible( true ); 27 } // main } // HelloSmiley 5

6 COMP16121 Sample Code Lecture 2 Sean Bechhofer, University of Manchester, Manchester, UK sean.bechhofer@manchester.ac.uk 1 StopClock 1 import javax.swing.jlabel; 2 import java.util.date; 3 import javax.swing.jframe; 4 import java.awt.event.actionlistener; 5 import java.awt.event.actionevent; 6 import javax.swing.jbutton; 7 import java.awt.container; 8 import java.awt.gridlayout; 9 10 /** 11 * Stop Clock example. Button stops and starts the clock, which 12 * records start time, stop time and elapsed time. 13 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 14 */ 15 public class StopClock extends JFrame implements ActionListener { /* Local instance variables */ 18 private boolean isrunning = false; 19 private Date startdate; 20 private Date stopdate; 21 private JLabel starttimejlabel = new JLabel("Not started"); 22 private JLabel stoptimejlabel = new JLabel("Not started"); 23 private JLabel elapsedtimejlabel = new JLabel("Not started"); /* Constructor */ 26 public StopClock() { 27 settitle( "Stop Clock" ); Container contents = getcontentpane(); 30 /* Grid layout with one column */ 31 contents.setlayout( new GridLayout( 0, 1 ) ); /* Add some labels */ 34 contents.add(new JLabel("Started at:")); 35 contents.add(starttimejlabel); 36 contents.add(new JLabel("Stopped at:")); 37 contents.add(stoptimejlabel); 38 contents.add(new JLabel("Elapsed time (seconds):")); 39 contents.add(elapsedtimejlabel); 1

7 40 41 /* Create a button */ 42 JButton startstopjbutton = new JButton("Start / Stop"); 43 /* Register me with the button as a listener */ 44 startstopjbutton.addactionlistener(this); 45 contents.add(startstopjbutton); /* Specify appropriate behaviour when the window is closed */ 48 setdefaultcloseoperation(exit_on_close); /* pack the frame */ 51 pack(); 52 } // StopClock public void actionperformed( ActionEvent evt ) { 55 if (! isrunning) { 56 /* Start the clock */ 57 startdate = new Date(); 58 starttimejlabel.settext("" + startdate); 59 stoptimejlabel.settext("running..."); 60 elapsedtimejlabel.settext("running..."); 61 isrunning = true; 62 // Need to pack again because label size may have changed 63 pack(); 64 } else { 65 /* Stop the clock and show the updated times */ 66 stopdate = new Date(); 67 stoptimejlabel.settext("" + stopdate); 68 long elapsedmilliseconds = 69 (stopdate.gettime() - startdate.gettime()); 70 elapsedtimejlabel.settext("" + elapsedmilliseconds / ); 71 isrunning = false; 72 // Need to pack again because label size may have changed 73 pack(); 74 } 75 } // actionperformed public static void main(string [] args) { 78 StopClock thestopclock = new StopClock(); 79 thestopclock.setvisible( true ); 80 } // main 81 } 2

8 2 Button 1 import java.awt.container; 2 import javax.swing.jframe; 3 import javax.swing.jbutton; 4 import java.awt.event.actionlistener; 5 import java.awt.event.actionevent; 6 7 /** 8 * Simple frame with a single button. 9 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 10 */ 11 public class Button extends JFrame implements ActionListener { private JButton thebutton = new JButton( "Press Me!" ); /* Constructor */ 16 public Button() { 17 settitle("one Button"); 18 /* Get the contents of the frame and add a label to it */ 19 Container contents = getcontentpane(); 20 contents.add( thebutton ); 21 thebutton.addactionlistener(this); /* Specify appropriate behaviour when the window is closed */ 24 setdefaultcloseoperation(exit_on_close); /* pack the frame */ 27 pack(); 28 } // OneButton public void actionperformed( ActionEvent evt ) { 31 System.out.println("Pressed!"); 32 } /* Main method to drive the program */ 35 public static void main(string [] args) { 36 Button thebutton = new Button(); 37 thebutton.setvisible( true ); 38 } // main } // OneButton 3

9 COMP16121 Sample Code Lecture 3 Sean Bechhofer, University of Manchester, Manchester, UK sean.bechhofer@manchester.ac.uk 1 GCD 1 import javax.swing.jtextfield; 2 import javax.swing.jframe; 3 import java.awt.event.actionlistener; 4 import javax.swing.jbutton; 5 import java.awt.event.actionevent; 6 import java.awt.gridlayout; 7 import javax.swing.jlabel; 8 import java.awt.container; 9 10 /** 11 * Calculates GCD of two integers. Simple GUI. 12 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 13 */ 14 public class GCD extends JFrame implements ActionListener { private JTextField number1jtextfield = new JTextField(20); 17 private JTextField number2jtextfield = new JTextField(20); 18 private JTextField resultjtextfield = new JTextField(20); public GCD() { 21 settitle("gcd"); 22 Container contents = getcontentpane(); 23 contents.setlayout(new GridLayout(0, 1)); 24 contents.add(new JLabel("Number 1")); 25 contents.add(number1jtextfield); 26 contents.add(new JLabel("Number 2")); 27 contents.add(number2jtextfield); 28 JButton computejbutton = new JButton("Compute"); 29 contents.add(computejbutton); 30 computejbutton.addactionlistener(this); 31 contents.add(new JLabel("GCD of Number 1 and Number 2")); 32 contents.add(resultjtextfield); 33 /* Specify appropriate behaviour when the window is closed */ 34 setdefaultcloseoperation(exit_on_close); pack(); 37 } // GCD public void actionperformed(actionevent e) { 1

10 40 int number1 = Integer.parseInt(number1JTextField.getText()); 41 int number2 = Integer.parseInt(number2JTextField.getText()); 42 int thegcd = greatestcommondivisor(number1, number2); 43 resultjtextfield.settext("" + thegcd); 44 } // actionperformed private static int greatestcommondivisor(int multiple1ofgcd, 47 int multiple2ofgcd) { 48 // Both multiple1ofgcd and multiple2ofgcd must be non-negative 49 while (multiple1ofgcd!= multiple2ofgcd) 50 if (multiple1ofgcd > multiple2ofgcd) 51 multiple1ofgcd = multiple1ofgcd - multiple2ofgcd; 52 else 53 multiple2ofgcd = multiple2ofgcd - multiple1ofgcd; 54 return multiple1ofgcd; 55 } // greatestcommondivisor public static void main(string [] args) { 58 GCD thegcd = new GCD(); 59 thegcd.setvisible( true ); 60 } // main 61 } // class GCD 2

11 2 GCDDisabled 1 import javax.swing.jtextfield; 2 import javax.swing.jframe; 3 import java.awt.event.actionlistener; 4 import javax.swing.jbutton; 5 import java.awt.event.actionevent; 6 import java.awt.gridlayout; 7 import javax.swing.jlabel; 8 import java.awt.container; 9 10 /** 11 * Calculates GCD of two integers. Simple GUI. 12 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 13 */ 14 public class GCDDisabled extends JFrame implements ActionListener { private JTextField number1jtextfield = new JTextField(20); 17 private JTextField number2jtextfield = new JTextField(20); 18 private JTextField resultjtextfield = new JTextField(20); public GCDDisabled() { 21 settitle("gcd"); 22 Container contents = getcontentpane(); 23 contents.setlayout(new GridLayout(0, 1)); 24 contents.add(new JLabel("Number 1")); 25 contents.add(number1jtextfield); 26 contents.add(new JLabel("Number 2")); 27 contents.add(number2jtextfield); 28 JButton computejbutton = new JButton("Compute"); 29 contents.add(computejbutton); 30 computejbutton.addactionlistener(this); 31 contents.add(new JLabel("GCD of Number 1 and Number 2")); 32 contents.add(resultjtextfield); 33 resultjtextfield.setenabled( false ); 34 /* Specify appropriate behaviour when the window is closed */ 35 setdefaultcloseoperation(exit_on_close); pack(); 38 } // GCDDisabled public void actionperformed(actionevent e) { 41 int number1 = Integer.parseInt(number1JTextField.getText()); 42 int number2 = Integer.parseInt(number2JTextField.getText()); 43 int thegcd = greatestcommondivisor(number1, number2); 44 resultjtextfield.settext("" + thegcd); 45 } // actionperformed private static int greatestcommondivisor(int multiple1ofgcd, 48 int multiple2ofgcd) { 49 // Both multiple1ofgcd and multiple2ofgcd must be non-negative 3

12 50 while (multiple1ofgcd!= multiple2ofgcd) 51 if (multiple1ofgcd > multiple2ofgcd) 52 multiple1ofgcd = multiple1ofgcd - multiple2ofgcd; 53 else 54 multiple2ofgcd = multiple2ofgcd - multiple1ofgcd; 55 return multiple1ofgcd; 56 } // greatestcommondivisor public static void main(string [] args) { 59 GCDDisabled thegcd = new GCDDisabled(); 60 thegcd.setvisible( true ); 61 } // main 62 } // class GCDDisabled 4

13 3 TimesTable 1 import javax.swing.jframe; 2 import java.awt.event.actionlistener; 3 import javax.swing.jtextfield; 4 import javax.swing.jtextarea; 5 import java.awt.container; 6 import javax.swing.jbutton; 7 import java.awt.borderlayout; 8 import java.awt.event.actionevent; 9 10 /** 11 * Displays a times table using a {@link JTextArea JTextArea}. 12 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 13 */ 14 public class TimesTable extends JFrame implements ActionListener { private JTextField multiplierjtextfield = new JTextField(5); 17 private JTextArea displayjtextarea = new JTextArea(15, 20); public TimesTable() { 20 settitle("times Table"); 21 Container contents = getcontentpane(); 22 contents.setlayout(new BorderLayout()); 23 contents.add(multiplierjtextfield, BorderLayout.NORTH); 24 contents.add(displayjtextarea, BorderLayout.CENTER); 25 JButton displayjbutton = new JButton("Display"); 26 contents.add(displayjbutton, BorderLayout.SOUTH); 27 displayjbutton.addactionlistener(this); setdefaultcloseoperation(exit_on_close); 30 pack(); 31 } // TimesTable public void actionperformed(actionevent e) { 34 displayjtextarea.settext(""); 35 int multiplier = Integer.parseInt(multiplierJTextField.getText()); 36 displayjtextarea.append(" \n"); 37 displayjtextarea.append(" Times table for " + multiplier + "\n"); 38 displayjtextarea.append(" \n"); 39 for (int thisnumber = 1; 40 thisnumber <= 10; 41 thisnumber = thisnumber + 1) 42 displayjtextarea.append(" " + thisnumber + " x " + 43 multiplier + " = " 44 + thisnumber * multiplier + "\n"); 45 displayjtextarea.append(" \n"); 46 } // actionperformed public static void main(string [] args) { 49 TimesTable thetimestable = new TimesTable(); 5

14 50 thetimestable.setvisible( true ); 51 } // main } // class TimesTable

15 4 GCDWithPanels 1 import javax.swing.jtextfield; 2 import javax.swing.jframe; 3 import java.awt.event.actionlistener; 4 import javax.swing.jbutton; 5 import java.awt.event.actionevent; 6 import java.awt.gridlayout; 7 import javax.swing.jlabel; 8 import java.awt.container; 9 import javax.swing.jpanel; /** 12 * Calculates GCD of two integers. GUI using nested panels for layout. 13 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 14 */ 15 public class GCDWithPanels extends JFrame implements ActionListener { private JTextField number1jtextfield = new JTextField(20); 18 private JTextField number2jtextfield = new JTextField(20); 19 private JTextField resultjtextfield = new JTextField(20); public GCDWithPanels() { 22 settitle("gcd"); 23 Container contents = getcontentpane(); 24 contents.setlayout(new GridLayout(0, 1)); JPanel numberfieldspanel = new JPanel(); 27 numberfieldspanel.setlayout( new GridLayout( 0, 2 ) ); 28 contents.add( numberfieldspanel ); numberfieldspanel.add(new JLabel("Number 1")); 31 numberfieldspanel.add(new JLabel("Number 2")); 32 numberfieldspanel.add(number1jtextfield); 33 numberfieldspanel.add(number2jtextfield); JPanel buttonandresultpanel = new JPanel(); 36 buttonandresultpanel.setlayout( new GridLayout( 0, 2 ) ); 37 contents.add( buttonandresultpanel ); JButton computejbutton = new JButton("Compute"); 40 buttonandresultpanel.add(computejbutton); 41 computejbutton.addactionlistener(this); JPanel resultpanel = new JPanel(); 44 resultpanel.setlayout( new GridLayout( 0, 1 ) ); 45 buttonandresultpanel.add( resultpanel ); resultpanel.add(new JLabel("GCD of Number 1 and Number 2")); 48 resultpanel.add(resultjtextfield); 49 /* Specify appropriate behaviour when the window is closed */ 7

16 50 setdefaultcloseoperation(exit_on_close); pack(); 53 } // GCDWithPanels public void actionperformed(actionevent e) { 56 int number1 = Integer.parseInt(number1JTextField.getText()); 57 int number2 = Integer.parseInt(number2JTextField.getText()); 58 int thegcd = greatestcommondivisor(number1, number2); 59 resultjtextfield.settext("" + thegcd); 60 } // actionperformed private static int greatestcommondivisor(int multiple1ofgcd, 63 int multiple2ofgcd) { 64 // Both multiple1ofgcd and multiple2ofgcd must be non-negative 65 while (multiple1ofgcd!= multiple2ofgcd) 66 if (multiple1ofgcd > multiple2ofgcd) 67 multiple1ofgcd = multiple1ofgcd - multiple2ofgcd; 68 else 69 multiple2ofgcd = multiple2ofgcd - multiple1ofgcd; 70 return multiple1ofgcd; 71 } // greatestcommondivisor public static void main(string [] args) { 74 GCDWithPanels thegcd = new GCDWithPanels(); 75 thegcd.setvisible( true ); 76 } // main 77 } // class GCDWithPanels 8

17 5 TimesTable2 1 import javax.swing.jframe; 2 import java.awt.event.actionlistener; 3 import javax.swing.jtextfield; 4 import javax.swing.jtextarea; 5 import java.awt.container; 6 import javax.swing.jbutton; 7 import java.awt.borderlayout; 8 import java.awt.event.actionevent; 9 import javax.swing.jpanel; 10 import java.awt.gridlayout; 11 import javax.swing.jlabel; /** 14 * Displays a times table using a {@link JTextArea JTextArea}. 15 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 16 */ 17 public class TimesTable2 extends JFrame implements ActionListener { private JTextField multiplierjtextfield = new JTextField(5); 20 private JTextField tablesizejtextfield = new JTextField(5); 21 private JTextArea displayjtextarea = new JTextArea(15, 20); public TimesTable2() { 24 settitle("times Table"); 25 Container contents = getcontentpane(); 26 contents.setlayout(new BorderLayout()); 27 JPanel numberspanel = new JPanel( new GridLayout( 2, 2 ) ); 28 contents.add( numberspanel, BorderLayout.NORTH ); 29 numberspanel.add( new JLabel( "Multiplier:" ) ); 30 numberspanel.add( multiplierjtextfield ); numberspanel.add( new JLabel( "Table size:" ) ); 33 numberspanel.add( tablesizejtextfield ); 34 contents.add(displayjtextarea, BorderLayout.CENTER); 35 JButton displayjbutton = new JButton("Display"); 36 contents.add(displayjbutton, BorderLayout.SOUTH); 37 displayjbutton.addactionlistener(this); setdefaultcloseoperation(exit_on_close); 40 pack(); 41 } // TimesTable public void actionperformed(actionevent e) { 44 displayjtextarea.settext(""); 45 int multiplier = Integer.parseInt(multiplierJTextField.getText()); 46 int tablesize = Integer.parseInt(tableSizeJTextField.getText()); 47 displayjtextarea.append(" \n"); 48 displayjtextarea.append(" Times table for " + multiplier + "\n"); 49 displayjtextarea.append(" \n"); 9

18 50 for (int thisnumber = 1; 51 thisnumber <= tablesize; 52 thisnumber = thisnumber + 1) 53 displayjtextarea.append(" " + thisnumber + " x " + 54 multiplier + " = " 55 + thisnumber * multiplier + "\n"); 56 displayjtextarea.append(" \n"); 57 } // actionperformed public static void main(string [] args) { 60 TimesTable2 thetimestable = new TimesTable2(); 61 thetimestable.setvisible( true ); 62 } // main } // class TimesTable

19 6 TimesTableScroll 1 import javax.swing.jframe; 2 import java.awt.event.actionlistener; 3 import javax.swing.jtextfield; 4 import javax.swing.jtextarea; 5 import java.awt.container; 6 import javax.swing.jbutton; 7 import java.awt.borderlayout; 8 import java.awt.event.actionevent; 9 import javax.swing.jpanel; 10 import java.awt.gridlayout; 11 import javax.swing.jlabel; 12 import javax.swing.jscrollpane; /** 15 * Displays a times table using a {@link JTextArea JTextArea}. 16 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 17 */ 18 public class TimesTableScroll extends JFrame implements ActionListener { private JTextField multiplierjtextfield = new JTextField(5); 21 private JTextField tablesizejtextfield = new JTextField(5); 22 private JTextArea displayjtextarea = new JTextArea(15, 20); public TimesTableScroll() { 25 settitle("times Table"); 26 Container contents = getcontentpane(); 27 contents.setlayout(new BorderLayout()); 28 JPanel numberspanel = new JPanel( new GridLayout( 2, 2 ) ); 29 contents.add( numberspanel, BorderLayout.NORTH ); 30 numberspanel.add( new JLabel( "Multiplier:" ) ); 31 numberspanel.add( multiplierjtextfield ); numberspanel.add( new JLabel( "Table size:" ) ); 34 numberspanel.add( tablesizejtextfield ); 35 contents.add( new JScrollPane ( displayjtextarea), 36 BorderLayout.CENTER ); 37 JButton displayjbutton = new JButton("Display"); 38 contents.add(displayjbutton, BorderLayout.SOUTH); 39 displayjbutton.addactionlistener(this); setdefaultcloseoperation(exit_on_close); 42 pack(); 43 } // TimesTableScroll public void actionperformed(actionevent e) { 46 displayjtextarea.settext(""); 47 int multiplier = Integer.parseInt(multiplierJTextField.getText()); 48 int tablesize = Integer.parseInt(tableSizeJTextField.getText()); 49 displayjtextarea.append(" \n"); 11

20 50 displayjtextarea.append(" Times table for " + multiplier + "\n"); 51 displayjtextarea.append(" \n"); 52 for (int thisnumber = 1; 53 thisnumber <= tablesize; 54 thisnumber = thisnumber + 1) 55 displayjtextarea.append(" " + thisnumber + " x " + 56 multiplier + " = " 57 + thisnumber * multiplier + "\n"); 58 displayjtextarea.append(" \n"); 59 } // actionperformed public static void main(string [] args) { 62 TimesTableScroll thetimestable = new TimesTableScroll(); 63 thetimestable.setvisible( true ); 64 } // main } // class TimesTableScroll

21 COMP16121 Sample Code Lecture 4 Sean Bechhofer, University of Manchester, Manchester, UK sean.bechhofer@manchester.ac.uk 1 GCDWithNew 1 import java.awt.container; 2 import java.awt.flowlayout; 3 import java.awt.gridlayout; 4 import java.awt.event.actionevent; 5 import java.awt.event.actionlistener; 6 7 import javax.swing.jbutton; 8 import javax.swing.jframe; 9 import javax.swing.jlabel; 10 import javax.swing.jpanel; 11 import javax.swing.jtextfield; /** 14 * Calculates GCD of two integers. GUI allows spawning of a new window. 15 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 16 */ 17 public class GCDWithNew extends JFrame implements ActionListener { private JTextField number1jtextfield = new JTextField(20); 20 private JTextField number2jtextfield = new JTextField(20); 21 private JTextField resultjtextfield = new JTextField(20); private JButton computejbutton = new JButton("Compute"); 24 private JButton newjbutton = new JButton("New"); public GCDWithNew() { 27 settitle("gcd"); 28 Container contents = getcontentpane(); 29 contents.setlayout(new GridLayout(0, 1)); JPanel numberfieldspanel = new JPanel(); 32 numberfieldspanel.setlayout( new GridLayout( 0, 2 ) ); 33 contents.add( numberfieldspanel ); numberfieldspanel.add(new JLabel("Number 1")); 36 numberfieldspanel.add(new JLabel("Number 2")); 37 numberfieldspanel.add(number1jtextfield); 38 numberfieldspanel.add(number2jtextfield); 39 1

22 40 JPanel buttonandresultpanel = new JPanel(); 41 buttonandresultpanel.setlayout( new GridLayout( 0, 2 ) ); 42 contents.add( buttonandresultpanel ); JPanel buttonpanel = new JPanel(); 45 buttonpanel.setlayout( new FlowLayout() ); 46 buttonandresultpanel.add( buttonpanel ); buttonpanel.add(computejbutton); 49 computejbutton.addactionlistener(this); buttonpanel.add(newjbutton); 52 newjbutton.addactionlistener(this); JPanel resultpanel = new JPanel(); 55 resultpanel.setlayout( new GridLayout( 0, 1 ) ); 56 buttonandresultpanel.add( resultpanel ); resultpanel.add(new JLabel("GCD of Number 1 and Number 2")); 59 resultpanel.add(resultjtextfield); 60 /* Specify appropriate behaviour when the window is closed */ 61 setdefaultcloseoperation(exit_on_close); pack(); 64 } // GCDWithNew public void actionperformed(actionevent e) { 67 if ( e.getsource() == computejbutton ) { 68 int number1 = Integer.parseInt(number1JTextField.getText()); 69 int number2 = Integer.parseInt(number2JTextField.getText()); 70 int thegcd = greatestcommondivisor(number1, number2); 71 resultjtextfield.settext("" + thegcd); 72 } else if ( e.getsource() == newjbutton ) { 73 GCDWithNew newone = new GCDWithNew(); 74 newone.setvisible( true ); 75 } 76 } // actionperformed private static int greatestcommondivisor(int multiple1ofgcd, 79 int multiple2ofgcd) { 80 // Both multiple1ofgcd and multiple2ofgcd must be non-negative 81 while (multiple1ofgcd!= multiple2ofgcd) 82 if (multiple1ofgcd > multiple2ofgcd) 83 multiple1ofgcd = multiple1ofgcd - multiple2ofgcd; 84 else 85 multiple2ofgcd = multiple2ofgcd - multiple1ofgcd; 86 return multiple1ofgcd; 87 } // greatestcommondivisor public static void main(string [] args) { 2

23 90 GCDWithNew thegcd = new GCDWithNew(); 91 thegcd.setvisible( true ); 92 } // main 93 } // class GCDWithNew 3

24 2 GCDWithNew2 1 import javax.swing.jtextfield; 2 import javax.swing.jframe; 3 import java.awt.event.actionlistener; 4 import javax.swing.jbutton; 5 import java.awt.event.actionevent; 6 import java.awt.gridlayout; 7 import javax.swing.jlabel; 8 import java.awt.container; 9 import javax.swing.jpanel; 10 import java.awt.flowlayout; 11 import java.awt.point; /** 14 * Calculates GCD of two integers. GUI allows spawning of a new window. 15 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 16 */ 17 public class GCDWithNew2 extends JFrame implements ActionListener { private JTextField number1jtextfield = new JTextField(20); 20 private JTextField number2jtextfield = new JTextField(20); 21 private JTextField resultjtextfield = new JTextField(20); private JButton computejbutton = new JButton("Compute"); 24 private JButton newjbutton = new JButton("New"); public GCDWithNew2() { 27 settitle("gcd"); 28 Container contents = getcontentpane(); 29 contents.setlayout(new GridLayout(0, 1)); JPanel numberfieldspanel = new JPanel(); 32 numberfieldspanel.setlayout( new GridLayout( 0, 2 ) ); 33 contents.add( numberfieldspanel ); numberfieldspanel.add(new JLabel("Number 1")); 36 numberfieldspanel.add(new JLabel("Number 2")); 37 numberfieldspanel.add(number1jtextfield); 38 numberfieldspanel.add(number2jtextfield); JPanel buttonandresultpanel = new JPanel(); 41 buttonandresultpanel.setlayout( new GridLayout( 0, 2 ) ); 42 contents.add( buttonandresultpanel ); JPanel buttonpanel = new JPanel(); 45 buttonpanel.setlayout( new FlowLayout() ); 46 buttonandresultpanel.add( buttonpanel ); buttonpanel.add(computejbutton); 49 computejbutton.addactionlistener(this); 4

25 50 51 buttonpanel.add(newjbutton); 52 newjbutton.addactionlistener(this); JPanel resultpanel = new JPanel(); 55 resultpanel.setlayout( new GridLayout( 0, 1 ) ); 56 buttonandresultpanel.add( resultpanel ); resultpanel.add(new JLabel("GCD of Number 1 and Number 2")); 59 resultpanel.add(resultjtextfield); 60 /* Specify appropriate behaviour when the window is closed */ 61 setdefaultcloseoperation(exit_on_close); pack(); 64 } // GCDWithNew public void actionperformed(actionevent e) { 67 if ( e.getsource() == computejbutton ) { 68 int number1 = Integer.parseInt(number1JTextField.getText()); 69 int number2 = Integer.parseInt(number2JTextField.getText()); 70 int thegcd = greatestcommondivisor(number1, number2); 71 resultjtextfield.settext("" + thegcd); 72 } else if ( e.getsource() == newjbutton ) { 73 GCDWithNew2 newone = new GCDWithNew2(); 74 newone.setlocation( new Point( this.getlocation().x + 10, 75 this.getlocation().y + 10 ) ); 76 newone.setvisible( true ); 77 } 78 } // actionperformed private static int greatestcommondivisor(int multiple1ofgcd, 81 int multiple2ofgcd) { 82 // Both multiple1ofgcd and multiple2ofgcd must be non-negative 83 while (multiple1ofgcd!= multiple2ofgcd) 84 if (multiple1ofgcd > multiple2ofgcd) 85 multiple1ofgcd = multiple1ofgcd - multiple2ofgcd; 86 else 87 multiple2ofgcd = multiple2ofgcd - multiple1ofgcd; 88 return multiple1ofgcd; 89 } // greatestcommondivisor public static void main(string [] args) { 92 GCDWithNew2 thegcd = new GCDWithNew2(); 93 thegcd.setvisible( true ); 94 } // main 95 } // class GCDWithNew2 5

26 3 GCDWithNew3 1 import javax.swing.jtextfield; 2 import javax.swing.jframe; 3 import java.awt.event.actionlistener; 4 import javax.swing.jbutton; 5 import java.awt.event.actionevent; 6 import java.awt.gridlayout; 7 import javax.swing.jlabel; 8 import java.awt.container; 9 import javax.swing.jpanel; 10 import java.awt.flowlayout; 11 import java.awt.point; /** 14 * Calculates GCD of two integers. GUI allows spawning of a new window. 15 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 16 */ 17 public class GCDWithNew3 extends JFrame implements ActionListener { private JTextField number1jtextfield = new JTextField(20); 20 private JTextField number2jtextfield = new JTextField(20); 21 private JTextField resultjtextfield = new JTextField(20); private JButton computejbutton = new JButton("Compute"); 24 private JButton newjbutton = new JButton("New"); public GCDWithNew3() { 27 settitle("gcd"); 28 Container contents = getcontentpane(); 29 contents.setlayout(new GridLayout(0, 1)); JPanel numberfieldspanel = new JPanel(); 32 numberfieldspanel.setlayout( new GridLayout( 0, 2 ) ); 33 contents.add( numberfieldspanel ); numberfieldspanel.add(new JLabel("Number 1")); 36 numberfieldspanel.add(new JLabel("Number 2")); 37 numberfieldspanel.add(number1jtextfield); 38 numberfieldspanel.add(number2jtextfield); JPanel buttonandresultpanel = new JPanel(); 41 buttonandresultpanel.setlayout( new GridLayout( 0, 2 ) ); 42 contents.add( buttonandresultpanel ); JPanel buttonpanel = new JPanel(); 45 buttonpanel.setlayout( new FlowLayout() ); 46 buttonandresultpanel.add( buttonpanel ); buttonpanel.add(computejbutton); 49 computejbutton.addactionlistener(this); 6

27 50 51 buttonpanel.add(newjbutton); 52 newjbutton.addactionlistener(this); JPanel resultpanel = new JPanel(); 55 resultpanel.setlayout( new GridLayout( 0, 1 ) ); 56 buttonandresultpanel.add( resultpanel ); resultpanel.add(new JLabel("GCD of Number 1 and Number 2")); 59 resultpanel.add(resultjtextfield); 60 /* Specify appropriate behaviour when the window is closed */ 61 setdefaultcloseoperation(dispose_on_close); pack(); 64 } // GCDWithNew public void actionperformed(actionevent e) { 67 if ( e.getsource() == computejbutton ) { 68 int number1 = Integer.parseInt(number1JTextField.getText()); 69 int number2 = Integer.parseInt(number2JTextField.getText()); 70 int thegcd = greatestcommondivisor(number1, number2); 71 resultjtextfield.settext("" + thegcd); 72 } else if ( e.getsource() == newjbutton ) { 73 GCDWithNew3 newone = new GCDWithNew3(); 74 newone.setlocation( new Point( this.getlocation().x + 10, 75 this.getlocation().y + 10 ) ); 76 newone.setvisible( true ); 77 } 78 } // actionperformed private static int greatestcommondivisor(int multiple1ofgcd, 81 int multiple2ofgcd) { 82 // Both multiple1ofgcd and multiple2ofgcd must be non-negative 83 while (multiple1ofgcd!= multiple2ofgcd) 84 if (multiple1ofgcd > multiple2ofgcd) 85 multiple1ofgcd = multiple1ofgcd - multiple2ofgcd; 86 else 87 multiple2ofgcd = multiple2ofgcd - multiple1ofgcd; 88 return multiple1ofgcd; 89 } // greatestcommondivisor public static void main(string [] args) { 92 GCDWithNew3 thegcd = new GCDWithNew3(); 93 thegcd.setvisible( true ); 94 } // main 95 } // class GCDWithNew3 7

28 4 LogGUI 1 import javax.swing.jframe; 2 import java.awt.event.actionlistener; 3 import javax.swing.jtextfield; 4 import javax.swing.jtextarea; 5 import java.awt.container; 6 import javax.swing.jbutton; 7 import java.awt.borderlayout; 8 import java.awt.event.actionevent; 9 import java.awt.gridlayout; 10 import javax.swing.jpanel; 11 import javax.swing.jlabel; /** 14 * Simple GUI that allows users to log messages. 15 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 16 */ 17 public class LogGUI extends JFrame implements ActionListener { /* GUI Components */ 20 private JTextField labelfield = new JTextField("label"); 21 private JTextArea messagetextarea = new JTextArea(15, 20); 22 private JButton logbutton = new JButton("Log"); 23 private JButton newbutton = new JButton("New"); /* The LogBook that we will log messages to */ 26 private LogBook logbook; /** 29 * Creates a new <code>loggui</code> instance. 30 * 31 alogbook The <code>logbook</code> that the GUI is 32 * connected to. 33 */ 34 public LogGUI( LogBook alogbook ) { 35 logbook = alogbook; 36 settitle("log"); 37 Container contents = getcontentpane(); 38 contents.setlayout(new BorderLayout()); JPanel labelpanel = new JPanel( new GridLayout( 0, 2 ) ); 41 labelpanel.add( new JLabel( "Label:" ) ); 42 labelpanel.add( labelfield ); contents.add( labelpanel, BorderLayout.NORTH ); 46 contents.add( messagetextarea, BorderLayout.CENTER ); JPanel buttonpanel = new JPanel( new GridLayout( 0, 2 ) ); 49 buttonpanel.add( logbutton ); 8

29 50 logbutton.addactionlistener( this ); buttonpanel.add( newbutton ); 53 newbutton.addactionlistener( this ); contents.add( buttonpanel, BorderLayout.SOUTH ); setdefaultcloseoperation( DISPOSE_ON_CLOSE ); 58 pack(); 59 } // LogGUI public void actionperformed( ActionEvent e ) { 62 if ( e.getsource() == logbutton ) { 63 /* Log the message */ 64 logbook.logmessage( labelfield.gettext(), 65 messagetextarea.gettext() ); 66 /* Now clear the text */ 67 messagetextarea.settext(""); 68 } else if ( e.getsource() == newbutton ) { 69 /* Create a new GUI with the same logbook */ 70 LogGUI newloggui = new LogGUI( logbook ); 71 newloggui.setvisible( true ); 72 } 73 } // actionperformed public static void main(string [] args) { 76 LogBook logbook = new LogBook( "My LogBook" ); 77 LogGUI theloggui = new LogGUI( logbook ); 78 theloggui.setvisible( true ); 79 } // main } // class LogGUI

30 5 LogBook 1 import java.text.simpledateformat; 2 import java.util.date; 3 4 /** 5 * A class that records information. 6 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 7 */ 8 public class LogBook { 9 10 /* private String logname; */ 11 private String log; 12 private SimpleDateFormat dateformat; /** 15 * Create a new <code>logbook</code> instance. 16 * 17 alogname name of the room. 18 */ 19 public LogBook( String alogname ) { 20 /* logname = alogname; */ 21 dateformat = new SimpleDateFormat( "hh:mm:ss " ); 22 log = ""; 23 } /** 26 * Log a message. 27 * 28 user a <code>string</code> value 29 message a <code>string</code> value 30 */ 31 public void logmessage( String label, 32 String message ) { 33 Date now = new Date(); String logmessage = "Time: " + dateformat.format( now ) + "\n" + 36 "Label: " + label + "\n"+ 37 "Note: " + message; /* Add the message to the log */ 40 log = log + logmessage + "\n"; /* Display the message */ 43 System.out.println( " " ); 44 System.out.println( logmessage ); 45 System.out.println( " " ); 46 } 47 } 10

31 6 LogGUI2 1 import javax.swing.jframe; 2 import java.awt.event.actionlistener; 3 import javax.swing.jtextfield; 4 import javax.swing.jtextarea; 5 import java.awt.container; 6 import javax.swing.jbutton; 7 import java.awt.borderlayout; 8 import java.awt.event.actionevent; 9 import java.awt.gridlayout; 10 import javax.swing.jpanel; 11 import javax.swing.jlabel; /** 14 * Simple GUI2 that allows labels to log messages. 15 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 16 */ 17 public class LogGUI2 extends JFrame implements ActionListener { /* GUI Components */ 20 private JTextField labelfield = new JTextField("label"); 21 private JTextArea messagetextarea = new JTextArea(15, 20); 22 private JButton logbutton = new JButton("Log"); 23 private JButton newbutton = new JButton("New"); 24 private JButton transcriptbutton = new JButton("Transcript"); /* The LogBook that we will log messages to */ 27 private LogBook2 logbook; /** 30 * Creates a new <code>loggui2</code> instance. 31 * 32 alogbook The <code>logbook</code> that the GUI is 33 * connected to. 34 */ 35 public LogGUI2( LogBook2 alogbook ) { 36 logbook = alogbook; 37 settitle("log"); 38 Container contents = getcontentpane(); 39 contents.setlayout(new BorderLayout()); JPanel labelpanel = new JPanel( new GridLayout( 0, 2 ) ); 42 labelpanel.add( new JLabel( "Label:" ) ); 43 labelpanel.add( labelfield ); contents.add( labelpanel, BorderLayout.NORTH ); 47 contents.add( messagetextarea, BorderLayout.CENTER ); JPanel buttonpanel = new JPanel( new GridLayout( 0, 3 ) ); 11

32 50 buttonpanel.add( logbutton ); 51 logbutton.addactionlistener( this ); buttonpanel.add( newbutton ); 54 newbutton.addactionlistener( this ); buttonpanel.add( transcriptbutton ); 57 transcriptbutton.addactionlistener( alogbook ); contents.add( buttonpanel, BorderLayout.SOUTH ); setdefaultcloseoperation( DISPOSE_ON_CLOSE ); 62 pack(); 63 } // LogGUI public void actionperformed( ActionEvent e ) { 66 if ( e.getsource() == logbutton ) { 67 /* Log the message */ 68 logbook.logmessage( labelfield.gettext(), 69 messagetextarea.gettext() ); 70 /* Now clear the text */ 71 messagetextarea.settext(""); 72 } else if ( e.getsource() == newbutton ) { 73 /* Create a new GUI with the same logbook */ 74 LogGUI2 newloggui = new LogGUI2( logbook ); 75 newloggui.setvisible( true ); 76 } 77 } // actionperformed public static void main(string [] args) { 80 LogBook2 logbook = new LogBook2( "LogBook" ); 81 LogGUI2 theloggui = new LogGUI2( logbook ); 82 theloggui.setvisible( true ); 83 } // main } // class LogGUI

33 7 LogBook2 1 import java.text.simpledateformat; 2 import java.util.date; 3 import java.awt.event.actionlistener; 4 import java.awt.event.actionevent; 5 6 /** 7 * A class that records information. 8 <a href="mailto:seanb@cs.man.ac.uk">sean Bechhofer</a> 9 */ 10 public class LogBook2 implements ActionListener { /* private String logname; */ 13 private String log; 14 private SimpleDateFormat dateformat; /** 17 * Create a new <code>logbook</code> instance. 18 * 19 alogname name of the room. 20 */ 21 public LogBook2( String alogname ) { 22 /* logname = alogname; */ 23 dateformat = new SimpleDateFormat( "hh:mm:ss " ); 24 log = ""; 25 } /** 28 * Log a message. 29 * 30 user a <code>string</code> value 31 message a <code>string</code> value 32 */ 33 public void logmessage( String label, 34 String message ) { 35 Date now = new Date(); String logmessage = "Time: " + dateformat.format( now ) + "\n" + 38 "Label: " + label + "\n"+ 39 "Note: " + message; /* Add the message to the log */ 42 log = log + logmessage + "\n"; 43 } public void actionperformed( ActionEvent e ) { 46 System.out.println("========================"); 47 System.out.println( log ); 48 System.out.println("========================"); 49 } 13

34 50 } 14