THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
Java Appletek II.
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
2
Webtechnológia 1
Applet GUI
• Az appletek a böngész! ablakában
jelennek meg
• háttér szín
• paraméter
• meghatározott méret
• platformok
• layout manager
• Az applet osztályok letöltése a
hálózaton
• alosztályok
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
3
Webtechnológia 1
Standard out
• Diagnosztikai, debug üzenetek
• standard out, standard error
• System.out, System.err
• Appletviewer
• consol ablak
• shell ablak
• Célszer"en kikapcsolható kiírás
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
4
Webtechnológia 1
Rendszer
tulajdonságok
• M"ködési környezet tulajdonságai
• java.util.Properties
• System.getProperty
"file.separator" File separator (for example, "/")
"java.class.version" Java class version number
"java.vendor" Java vendor-specific string
"java.vendor.url" Java vendor URL
"java.version" Java version number
"line.separator" Line separator
"os.arch" Operating system architecture
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
5
Webtechnológia 1
Rendszer
tulajdonságok (pl.)
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class GetOpenProperties extends JApplet {
private String[] propertyNames = {"file.separator",
"line.separator",
"path.separator",
"java.class.version",
"java.vendor",
"java.vendor.url",
"java.version",
"os.name",
"os.arch",
"os.version"};
private final int numProperties = propertyNames.length;
private JLabel[] values;
private javax.swing.Timer timer;
private int currentPropNum = 0;
public void init() {
//Execute a job on the event-dispatching thread:
//creating this applet's GUI.
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
createGUI();
}
});
} catch (Exception e) {
System.err.println("createGUI didn't successfully complete");
}
}
public void start() {
//Update the GUI every 1/4 second or so.
timer = new javax.swing.Timer(250, new PropertyUpdater());
timer.setCoalesce(false);
timer.start();
}
public void stop() {
if (timer != null) {
timer.stop();
}
}
public void destroy() {
//Execute a job on the event-dispatching thread:
//destroying this applet's GUI.
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
remove(getContentPane());
}
});
} catch (Exception e) { }
}
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
6
Webtechnológia 1
Rendszer
tulajdonságok (pl.)
private void createGUI() {
JPanel contentPane = new JPanel(new GridBagLayout());
GridBagConstraints labelConstraints =
new GridBagConstraints();
GridBagConstraints valueConstraints =
new GridBagConstraints();
labelConstraints.anchor = GridBagConstraints.WEST;
labelConstraints.ipadx = 10;
valueConstraints.fill = GridBagConstraints.HORIZONTAL;
valueConstraints.gridwidth = GridBagConstraints.REMAINDER;
valueConstraints.weightx = 1.0; //Extra space to values column.
//Set up the Label arrays.
JLabel[] names = new JLabel[numProperties];
values = new JLabel[numProperties];
String firstValue = "<not read yet>";
//Fonts
Font headingFont = new Font("SansSerif", Font.BOLD, 14);
Font propertyFont = new Font("SansSerif", Font.BOLD, 12);
Font valueFont = new Font("SansSerif", Font.PLAIN, 12);
//Add headings.
contentPane.add(createHeading("Property Name", headingFont), labelConstraints);
contentPane.add(createHeading("Value", headingFont), valueConstraints);
for (int i = 0; i < numProperties; i++) {
names[i] = new JLabel(propertyNames[i]);
names[i].setFont(propertyFont);
contentPane.add(names[i], labelConstraints);
values[i] = new JLabel(firstValue);
values[i].setFont(valueFont);
contentPane.add(values[i], valueConstraints);
names[i].setLabelFor(values[i]);
}
contentPane.setBorder(BorderFactory.createCompoundBorder(
BorderFactory.createLineBorder(Color.black),
BorderFactory.createEmptyBorder(5,20,5,10)));
setContentPane(contentPane);
}
private JLabel createHeading(String text, Font font) {
JLabel l = new JLabel(text);
l.setFont(font);
l.setBorder(BorderFactory.createCompoundBorder(
BorderFactory.createEmptyBorder(0,0,5,0),
BorderFactory.createMatteBorder(0,0,1,0,Color.black)));
return l;
}
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
7
Webtechnológia 1
Rendszer
tulajdonságok (pl.)
private class PropertyUpdater implements ActionListener {
private String value;
public void actionPerformed(ActionEvent e) {
if (currentPropNum < numProperties) {
try {
value = System.getProperty(propertyNames[currentPropNum]);
if (value == null) {
value = "<null value!>";
}
values[currentPropNum].setText(value);
} catch (SecurityException exc) {
values[currentPropNum].setText("Could not read: SECURITY EXCEPTION!");
}
currentPropNum++;
} else {
timer.stop();
}
}
}
}
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
8
Webtechnológia 1
Többszálúság
• Id!igényes taszk végrehajtása a
eseménykezelés felfüggesztése
nélkül
• Periódikusan ismétl!d!
tevékenységek végrehajtása
• Szerver alkalmazások
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
9
Webtechnológia 1
Swing és a szálak
• Swing komponensek általában nem
támogatják a többszálon való
hozzáférés (nem thread safe-ek)
• hozzáférés csak az eseménykezel!
szálon
• komponens realizálás
• ->eseménykezel! szál
• Swing komponens megrajzolása,
eseménykezelés
• paint(), ActionPerformed()
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
10
Webtechnológia 1
Swing és a szálak
(folyt.)
public class MyApplication {
public static void main(String[] args) {
JFrame f = new JFrame("Labels");
// Add components to
// the frame here...
f.pack();
f.show();
// Don't do any more GUI work here...
}
}
realizálás
biztonságos
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
11
Webtechnológia 1
Swing és a szálak
(folyt.)
• Applet GUI létrehozható az init()
metódusban
• realizálás start()-kor
• ne legyen id!igényes init()
• külön szál indítása
• Thread safe bárhonnan
• repaint(), revalidate()
• add...Listener(),
remove...Listener()
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
12
Webtechnológia 1
Swing és a szálak
(folyt.)
• Realizált GUI
• UI-event (AWT event) driven
m"ködes
• GUI update igény más forrásból
(nem AWT event)
• invokeAndWait(), invokeLater()
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
13
Webtechnológia 1
Swing és a szálak
(folyt.)
• Szálak Swing barát létrehozása
• Timer class
• periódikus tevékenységekhez
• actionPerformed() metódus
végrehajtása az eseménykezel!
szálon
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
14
Webtechnológia 1
Többszálú
appletek
• Az appletnek lehet több szála
• GUI létrehozása az eseménykezel!
szálból
• init, start, stop, destroy nem kerül
meghívásra innen
• Szálak használata
• Id!igényes inicializálás
• Animáció
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
15
Webtechnológia 1
Szálak példa 1.
import javax.swing.*;
import java.awt.*;
public class PrintThread extends JApplet {
JTextArea display;
public void init() {
//Execute a job on the event-dispatching thread:
//creating this applet's GUI.
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
createGUI();
}
});
} catch (Exception e) {
System.err.println("createGUI didn't successfully complete");
}
addItem("init: " + threadInfo(Thread.currentThread()),
false); //not on event-dispatching thread
}
private void createGUI() {
//Create the text area and make it uneditable.
display = new JTextArea(1, 80);
display.setEditable(false);
//Set the layout manager so that the text area
//will be as wide as possible.
getContentPane().setLayout(new GridLayout(1,0));
//Add the text area (in a scroll pane) to the applet.
getContentPane().add(new JScrollPane(display));
addItem("createGUI: " + threadInfo(Thread.currentThread()),
true); //on event-dispatching thread
}
public void start() {
addItem("start: " + threadInfo(Thread.currentThread()),
false); //not on event-dispatching thread
}
public void stop() {
addItem("stop: " + threadInfo(Thread.currentThread()),
false); //not on event-dispatching thread
}
public void destroy() {
addItem("destroy: " + threadInfo(Thread.currentThread()),
false); //not on event-dispatching thread
//Execute a job on the event-dispatching thread:
//destroying this applet's GUI.
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
getContentPane().removeAll();
addItem("doing removeAll: "
+ threadInfo(Thread.currentThread()),
true); //on event-dispatching thread
}
});
} catch (Exception e) { }
}
String threadInfo(Thread t) {
return "thread=" + t.getName() + ", "
+ "thread group=" + t.getThreadGroup().getName();
}
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
16
Webtechnológia 1
Szálak példa 1.
(folyt.)
void addItem(String newWord, boolean onEDT) {
final String s = newWord + "\n";
System.out.println(newWord);
if (onEDT) {
display.append(s);
} else {
//Execute a job on the event-dispatching thread:
//updating this applet's GUI.
try {
SwingUtilities.invokeAndWait(new Runnable() {
public void run() {
display.append(s);
}
});
} catch (Exception e) { }
}
}
}
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
17
Webtechnológia 1
Szálak példa 2.
import java.awt.*;
import java.applet.Applet;
/*
* Based on Arthur van Hoff's animation examples, this applet
* can serve as a template for all animation applets.
*/
public class AnimatorApplet extends Applet implements Runnable {
int frameNumber = -1;
int delay;
Thread animatorThread;
boolean frozen = false;
public void init() {
String str;
int fps = 10;
//How many milliseconds between frames?
str = getParameter("fps");
try {
if (str != null) {
fps = Integer.parseInt(str);
}
} catch (Exception e) {}
delay = (fps > 0) ? (1000 / fps) : 100;
}
public void start() {
if (frozen) {
//Do nothing. The user has requested that we
//stop changing the image.
} else {
//Start animating!
if (animatorThread == null) {
animatorThread = new Thread(this);
}
animatorThread.start();
}
}
public void stop() {
//Stop the animating thread.
animatorThread = null;
}
public boolean mouseDown(Event e, int x, int y) {
if (frozen) {
frozen = false;
start();
} else {
frozen = true;
stop();
}
return true;
}
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
18
Webtechnológia 1
Szálak példa 2.
(folyt.)
public void run() {
//Just to be nice, lower this thread's priority
//so it can't interfere with other processing going on.
Thread.currentThread().setPriority(Thread.MIN_PRIORITY);
//Remember the starting time.
long startTime = System.currentTimeMillis();
//This is the animation loop.
while (Thread.currentThread() == animatorThread) {
//Advance the animation frame.
frameNumber++;
//Display it.
repaint();
//Delay depending on how far we are behind.
try {
startTime += delay;
Thread.sleep(Math.max(0,
startTime-System.currentTimeMillis()));
} catch (InterruptedException e) {
break;
}
}
}
//Draw the current frame of animation.
public void paint(Graphics g) {
g.drawString("Frame " + frameNumber, 0, 30);
}
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
19
Webtechnológia 1
Szálak példa 3.
• getAudioClip
• csak miután végzett tér vissza
• betöltés különszálon
• termel!/fogyasztó felállás
• SoundLoader/SoundExample
• SoundList
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
20
Webtechnológia 1
Együttm!ködés szerver-
oldali alkalmzásokkal
• java.net csomag használható
• csak azzal a hoszttal, melyr!l az
applet jött
• getCodeBase().getHost()
• t"zfalak?
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
21
Webtechnológia 1
Biztonsági korlátok
megkerülése szerverrel
• Applet nem írhat és olvashat fájlokat a
helyi fájlrendszeren
• adatok tárolása szerver alk. segítségével
• Hálózati kapcsolat csak a származási
hoszttal
• szerver alk. építi ki a hálózati
kapcsolatot más hosztokhoz
• Applet nem indíthat alkalmazásokat a
futtató gépen
• szerveroldalon futhatnak alkalmazások
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
22
Webtechnológia 1
A kész applet
• Debug konzol üzenetek kikapcsolva
• O# screen nem fogyaszt CPU-t
• stop() metódus
• hang kikapcsolható
• getParameterInfo()
• getAppletInfo()
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
JNLP és
Java Web Start
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
24
Webtechnológia 1
Java Web Start
• Java alkalmazások elérése Web szerveren
keresztül
• böngész! kontextuson kívüli
végrehajtás
• végrahajtás homokozóban
• hozzáférési kérések
• kliens oldalon
• Java Web Start
• szerveroldal
•
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
25
Webtechnológia 1
Java Web Start
példa
import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.net.*;
public class TheTime {
public static void main(String args[]) {
JFrame frame = new JFrame("Time Check");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JLabel label = new JLabel();
Container content = frame.getContentPane();
content.add(label, BorderLayout.CENTER);
String message = "missing";
BufferedReader reader = null;
try {
Socket socket = new Socket("time.nist.gov", 13);
InputStream is = socket.getInputStream();
InputStreamReader isr = new InputStreamReader(is);
reader = new BufferedReader(isr);
reader.readLine(); // skip blank line
message = reader.readLine();
} catch (MalformedURLException e) {
System.err.println("Malformed: " + e);
} catch (IOException e) {
System.err.println("I/O Exception: " + e);
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException ignored) {
}
}
}
label.setText(message);
frame.pack();
frame.show();
}
}
TheTime.java
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
26
Webtechnológia 1
Java Web Start
példa (folyt.)
<?xml version="1.0" encoding="UTF-8"?>
<jnlp spec="1.0+"
codebase="file:///c:/jdc/jnlp/"
>
<information>
<title>Time Check</title>
<vendor>Java Developer Connection</vendor>
<homepage href="/jdc" />
<description>Demonstration of JNLP</description>
</information>
<offline-allowed/>
<security>
<j2ee-application-client-permissions/>
</security>
<resources>
<j2se version="1.2+" />
<jar href="/developer/technicalArticles/Programming/jnlp/JNLPTime.jar"/>
</resources>
<application-desc main-class="TheTime" />
</jnlp>
time.jnlp
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
a -
Scientistshave recently discoveredthat variouscomplexsystemshave
antlnderlyihg~..'~tJ;i~e~tu"eg~Ye'l"rne(;lb9.$ha red organili ng principies.
Thisinsighthas important impli~ationsfor a hostof
applications,from drugdevelopmentto Internet security
BYALBERT-U\SZLO BARABASI ANDERICBONABEAU
50 SCIENTIFIC AMERICAN MAY 2003
27
Webtechnológia 1
Java Web Start
példa (folyt.)
THE INTERNET,mapped on the opposite page, is a scale-free network in that some siteS(starbursts and detail above)have a seemingly unlimited number of connections to other sites. This map, made on February 6, 2003, traces the shortest routes from a test Web sinHo about100,000others, using like colors for similar Web addresses.
