Xây dựng và thiết kế chương trình minh họa thuật toán Dijkstra
Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (400.82 KB, 27 trang )
!
"
#
$%"
#
&
#
&'
(
(
$'
#
!
(
)
!"#$%&
!"#$&
'()*+,,
()*+,,,
--.
/'()*0/'()*0.
1$2/'()*0.
3$/'()*0.
/'()*0.
24%5678
-".
349:;%.
%<%6-&$&7.
6%-&===&->->->7.
$6<+.<.??78
$6"<+."<."??78
6%-&=&->/0/"07.
6/0/"0<<,7/0/"0<()*.
@
@
6%7.
@
24678
2.
$62<+.2<.2??78
/20</0/20.AABC
D
E
$
E
FG
%
F
2
2</0/20
AAH
G
1$2/20<.
AAIG
D
FJ
D
F
C
D
$
E
E
3$/20<$.
@
AA
F
E
1$2/0<,.
/0<,.
3$/0<.
@
2!"#$678
-2-%.
AA
E
E
$#
E
K63$/078
%<()*.
AAIJ
$G
E
%I$FJ
D
/0
L
I
G
E
%C
E
%
FJ
D
AA
FJ
$62<+.2<.2??78
63$/20>>6%/20778
%</20.
<2.
@
@
AAM#J
FC
E
FJ
D
J
F
E
FJ
D
3$/0<.
AA!
FJ
D
F
D
FJ
D
$I
63$/078
$62<+.2<.2??78
63$/20>>6/0?/0/20/20778
AAM
D
E
D
2
/20</0?/0/20.
AA92
1$2/20<.
@
@
@
@
@
N%5678
4.
349:;%.
%<%6-&O&7.
%$6%-&?!==P&--7.
%$6%-&=<&-7.
<1$2/0.
O6Q<78
%$6%-&=<&-7.
<1$2/0.
@
%$6%-&=&-7.
%$6%-&P?!=&-/07.
6%7.
@
*+,-. )
MRSTS:%U%$V2WX2
*/0 1, )
N%YZ[F\]^2^2_ZF`-Za6%b7-
R-cd-aL]UZ!"#$
package Dijkstra3;
import java.awt.Button;
import java.awt.Event;
import java.awt.GridLayout;
import java.awt.Panel;
class Options extends Panel {
/**
*
*/
private static final long serialVersionUID = 1L;
// Dat cac Options ben trai man hinh ung dung
Button b1 = new Button("Clear");
Button b2 = new Button("Run");
Button b3 = new Button("Step");
Button b4 = new Button("Reset");
Button b5 = new Button("Example");
Button b6 = new Button("Exit");
Button b7 = new Button("About");
GraphAlgorithm parent;
boolean Locked=false;
Options(GraphAlgorithm myparent) {
parent = myparent;
setLayout(new GridLayout(7, 1, 0, 10));
add(b1);
add(b2);
add(b3);
add(b4);
add(b5);
add(b7);
add(b6);
}
public boolean action(Event evt, Object arg) {
if (evt.target instanceof Button) {
//Neu la JButton "Step" va Unlock thi thuc hien buoc dau tien va
hien thi "Nextstep" len JButton,
//nguoc lai thi khong thuc hien
if (((String)arg).equals("Step")) {
if (!Locked) {
b3.setLabel("Next step");
parent.graphcanvas.stepalg();
}
else parent.documentation.doctext.showline("locked");
}
//Neu la JButton "Nextstep" thi thuc hien buoc tiep thep
if (((String)arg).equals("Next step")){
parent.graphcanvas.nextstep();
}
//Neu la JButton "Reset" thi thuc hien reset
if (((String)arg).equals("Reset")) {
parent.graphcanvas.reset();
b3.setLabel("Step");
parent.documentation.doctext.showline("all items");
}
//Neu la JButton "Clear" thi xoa graphics
if (((String)arg).equals("Clear")) {
parent.graphcanvas.clear();
b3.setLabel("Step");
parent.documentation.doctext.showline("all items");
}
//Neu la JButton "Run" va Unlock thi thuc hien tung buoc mac dinh
//nguoc lai thi khong thuc hien
if (((String)arg).equals("Run")) {
if (!Locked)
parent.graphcanvas.runalg();
else parent.documentation.doctext.showline("locked");
}
//Neu la JButton "Example" va Unlock thi thuc hien default graphics
//nguoc lai thi khong thuc hien
if (((String)arg).equals("Example")) {
if (!Locked)
parent.graphcanvas.showexample();
else parent.documentation.doctext.showline("locked");
}
//Neu la JButton "About" thi hien thi dialog About
if(((String)arg).equals("About")){
dialog dig = new dialog();
}
//Neu la JButton "Exit" thi thoat khoi chuong trinh
if (((String)arg).equals("Exit")) {
System.exit(0);
}
}
return true;
}
public void lock() {
Locked=true;
}
public void unlock() {
Locked=false;
b3.setLabel("Step");
}
}
*$/0 2)
!YWeRSC$V2fZ
`eg2W2^h%biZF`$jZ$VaL]^k
U!"#$
package Dijkstra3;
import java.awt.BorderLayout;
import java.awt.Choice;
import java.awt.Event;
import java.awt.GridLayout;
import java.awt.Label;
import java.awt.Panel;
import java.awt.TextArea;
class Documentation extends Panel {
// Documentaion huong dan o phia tren man hinh ung dung
DocOptions docopt = new DocOptions(this);
DocText doctext = new DocText();
Documentation() {
setLayout(new BorderLayout(10, 10));
add("West", docopt);
add("Center", doctext);
}
}
class DocOptions extends Panel {
//Tao Choice huong dan ben trai man hinh ung dung
Choice doc = new Choice();
Documentation parent;
DocOptions(Documentation myparent) {
setLayout(new GridLayout(2, 1, 5, 0));
parent = myparent;
add(new Label("DOCUMENTATION:"));
doc.addItem("draw nodes");
doc.addItem("remove nodes");
doc.addItem("move nodes");
doc.addItem("the startnode");
doc.addItem("draw arrows");
doc.addItem("change weights");
doc.addItem("remove arrows");
doc.addItem("clear / reset");
doc.addItem("run algorithm");
doc.addItem("step through");
doc.addItem("example");
doc.addItem("about");
doc.addItem("exit");
doc.addItem("all items");
add(doc);
}
public boolean action(Event evt, Object arg) {
//Ham xu ly Choice
if (evt.target instanceof Choice) {
String str=new String(doc.getSelectedItem());
parent.doctext.showline(str);
}
return true;
}
}
class DocText extends TextArea {
//TextDocumentation huong dan cho cac Choice va JButton
final String drawnodes = new String("DRAWING NODES:\n"+
"Draw a node by clicking the mouse on the screen application.\n\n");
final String rmvnodes = new String("REMOVE NODES:\n"+
"To remove a node press <ctrl> and click on the node.\n"+
"You can not remove the startnode.\n"+
"Select another startnode, then you can remove the node.\n\n");
final String mvnodes = new String("MOVING NODES\n"+
"To move a node press <Shift>, click on the node,\nand drag it to"+
" its new position.\n\n");
final String startnode = new String("STARTNODE:\n"+
"The startnode is blue, other nodes are grey.\n"+
"The first node you draw on the screen will be the startnode.\n"+
"To select another startnode press <ctrl>, click on the startnode,\n"+
"and drag the mouse to another node.\n"+
"To delete the startnode, first select another startnode, and then"+
"\nremove the node the usual way.\n\n");
final String drawarrows = new String("DRAWING ARROWS:\n"+
"To draw an arrow click mouse in a node,"+
"and drag it to another node.\n\n");
final String weight = new String("CHANGING WEIGHTS:\n"+
"To change the weight of an arrow, click on the arrowhead and drag\n"+
"it along the arrow.\n\n");
final String rmvarrows = new String("REMOVE ARROWS:\n"+
"To remove an arrow, change its weight to 0.\n\n");
final String clrreset = new String("<CLEAR> BUTTON: "+
"Remove the current graph from the screen.\n"+
"<RESET> BUTTON: "+
"Remove the results of the algorithm from the graph,\n"+
" and unlock screen.\n\n");
final String runalg = new String("<RUN> BUTTON: "+
"Run the algorithm on the graph, there will be a time\n" +
"delay of +/- 1 second between steps.\n"+
"To run the algorithm slower, use <STEP>.\n");
final String step = new String("<STEP> BUTTON: " +
"An opportunity to step through the algorithm.\n");
final String example = new String("<EXAMPLE> BUTTON: "+
"Displays a default graph on the screen for you.\n"+
"You can then use <STEP> or <RUN>\n");
final String exitbutton = new String("<EXIT> BUTTON: " +
"Only works if applet is run with appletviewer.\n");
final String aboutbutton = new String("<ABOUT> BUTTON: " +
"Show about Dijkstra program information.\n");
final String toclose = new String("ERROR: "+
"This position is to close to another node/arrow.\n");
final String done = new String("Algorithm has finished, " +
"follow green arrows from startnode to any node "+
"to get\nthe shortest path to " +
"the node. The length of the path is written in the node.\n" +
"press <RESET> to reset the graph, and unlock the screen.");
final String some = new String("Algorithm has finished, " +
"follow green arrows from startnode to any node "+
"to get\nthe shortest path to " +
"the node. The length of the path is written in the node.\n" +
"There are no paths from the startnode to any gray node.\n" +
"press <RESET> to reset the graph, and unlock the screen.");
final String none = new String("Algorithm has finished, " +
"there are no nodes reachable from the start node.\n"+
"press <RESET> to reset the graph, and unlock the screen.");
final String maxnodes = new String("ERROR: "+
"Maximum number of nodes reached!\n\n");
final String info = new String("DOCUMENTATION:\n"+
"You can scroll through the documentation or get documentation\n"+
"on a specific "+
"item by selecting the item on the left.\nSelecting <All items> "+
"brings you back "+
" to the scrolling text.\n\n");
final String locked = new String("ERROR: "+
"Keyboard/mouse locked for this action.\n"+
"Either press <NEXT STEP> or <RESET>.\n");
final String doc = info + drawnodes + rmvnodes + mvnodes +
startnode + drawarrows + weight + rmvarrows +
clrreset + runalg + step + example + aboutbutton +
exitbutton;
DocText() {
super(5, 2);
setEditable(false);
setText(doc);
}
public void showline(String str) {
if (str.equals("draw nodes")) setText(drawnodes);
else if (str.equals("remove nodes")) setText(rmvnodes);
else if (str.equals("move nodes")) setText(mvnodes);
else if (str.equals("the startnode")) setText(startnode);
else if (str.equals("draw arrows")) setText(drawarrows);
else if (str.equals("change weights")) setText(weight);
else if (str.equals("remove arrows")) setText(rmvarrows);
else if (str.equals("clear / reset")) setText(clrreset);
else if (str.equals("run algorithm")) setText(runalg);
else if (str.equals("step through")) setText(step);
else if (str.equals("example")) setText(example);
else if (str.equals("exit")) setText(exitbutton);
else if (str.equals("about")) setText(aboutbutton);
else if (str.equals("all items")) setText(doc);
else if (str.equals("toclose")) setText(toclose);
else if (str.equals("done")) setText(done);
else if (str.equals("locked")) setText(locked);
else if (str.equals("maxnodes")) setText(maxnodes);
else if (str.equals("none")) setText(none);
else if (str.equals("some")) setText(some);
else setText(str);
}
}
*/0 0)
2l%ml-n2o
package Dijkstra3;
import java.awt.*;
import java.awt.Component;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPanel;
class dialog extends JDialog implements ActionListener{
//tao Button OK
JButton jb=new JButton("OK");
//tao JPanel
JPanel jp1=new JPanel();
JPanel jp2=new JPanel(new GridLayout(3,1));
JPanel jp3=new JPanel();
ImageIcon img=new
ImageIcon(this.getClass().getResource("/nhanntv/nhanntv1.png"));
//tao JLabel
JLabel jlb1=new JLabel(img);
JLabel jlb2=new JLabel("************Program Java to************");
JLabel jlb3=new JLabel("****Dijkstra Algorithm Program Demo****");
JLabel jlb4=new JLabel("***CopyWrite @2011 Edit by Nhanntv***");
//Tao Layout
GridBagLayout gb=new GridBagLayout();
GridBagConstraints gbc=new GridBagConstraints();
private static final long serialVersionUID = 1L;
public dialog(){
setSize(300,200);
setLayout(gb);
jp1.add(jlb1);
jp2.add(jlb2);
jp2.add(jlb3);
jp2.add(jlb4);
jb.addActionListener(this);
jp3.add(jb);
gbc.fill=GridBagConstraints.EAST;
addComponent(jp1,0,0,4,10);
gbc.fill=GridBagConstraints.NORTHWEST;
addComponent(jp2,0,10,3,15);
gbc.fill=GridBagConstraints.NORTHWEST;
addComponent(jp3,3,15,1,5);
this.setVisible(true);
}
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(e.getSource()==jb){
this.dispose();
}
}
public void addComponent(Component c,int row,int col,int nrow,int ncol){
gbc.gridy=row;// toa do y
gbc.gridx=col;// toa do x
gbc.gridheight=nrow;// so dong chiem
gbc.gridwidth=ncol;// so cot chiem
gb.setConstraints(c,gbc);
add(c);
}
}
*/0 3,/ )
p$%2fFqhrC$V-YZUZk
jLo2^VFnFst$a6M$1u7-Z%C
YF\2_Ta-cGL]2fVFn-F$#ojkWaFqhk
U!"#$
package Dijkstra3;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Event;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Point;
class GraphCanvas extends Canvas implements Runnable {
// drawing area for the graph
final int MAXNODES = 20;
final int MAX = MAXNODES+1;
final int NODESIZE = 26;
final int NODERADIX = 13;
final int DIJKSTRA = 1;
// basic graph information
Point node[] = new Point[MAX]; // node
int weight[][] = new int[MAX][MAX]; // weight of arrow
Point arrow[][] = new Point[MAX][MAX]; // current position of arrowhead
Point startp[][] = new Point[MAX][MAX]; // start and
Point endp[][] = new Point[MAX][MAX]; // endpoint of arrow
float dir_x[][] = new float[MAX][MAX]; // direction of arrow
float dir_y[][] = new float[MAX][MAX]; // direction of arrow
// graph information while running algorithm
boolean algedge[][] = new boolean[MAX][MAX];
int dist[] = new int[MAX];
int finaldist[] = new int[MAX];
Color colornode[] = new Color[MAX];
boolean changed[] = new boolean[MAX]; // indicates distance change during
algorithm
int numchanged =0;
int neighbours=0;
int step=0;
// information used by the algorithm to find the next
