, JavaBeans (contrained properties). , , . .. . , PropertyVetoException. set - throws PropertyVetoException, set -. , , , .
. , get - set -. set - PropertyVetoException
public void <PropertyName> ( param) throws PropertyVetoException.
/ .
addPropertyChangeListener()
RemovePropertyChangeListener()
addVetoableChangeListener(VetoableChangeListener v) removeVetoableChangeListener(VetoableChangeListener v). VetoableChangeListener
void vetoableChange(PropertyChangeEvent evt) throws PropertyVetoException().
PropertyChangeSupport, , java.beans VetoableChangeSupport. , .
SomeBean, . someProperty() . .
/* # 26: bean- : SomeBean.java */
import java.beans.*;
public class SomeBean {
private String someProperty = null;
private VetoableChangeSupport vcs;
public SomeBean(){
vcs = new VetoableChangeSupport(this);
}
public void addVetoableChangeListener
(VetoableChangeListener pcl){
vcs.addVetoableChangeListener(pcl);
}
public void removeVetoableChangeListener
(VetoableChangeListener pcl){
pcs.removePropertyChangeListener(pcl);
}
public String getSomeProperty(){
return someProperty;
}
public void setSomeProperty(String value) throws
PropertyVetoException{
vcs.fireVetoableChange(someProperty, someProperty, value);
someProperty = value;
}
}
, . PropertyChangeSupport VetoableChangeSupport set - throws PropertyVetoException. someProperty , .
|
|
|
. , , / . .
ActionEvent, .
13
1. . JTextField, JButton JLabel. , .
2. JPanel . ; . BorderLayout.
3. 2 , , .
4. 2 , , , . ,
ArrayList.
5. 2 . . , TreeSet.
6. 
JLabel, : 
; , JTextField, , (, 0.1) . x=0. , . , .
7. , , ..
8. , GIF-, .
9. (, , ). . .
10. . 1 9.
11. . , , , . .
12. ( ). . .
13. / . ,
/.
14. 12 , .
15. . , .
16. ( ) / /.
|
|
|
B
4 , , , .
13
13.1.
?
1) FlowLayout;
2) GridLayout;
3) BorderLayout;
4) CardLayout.
13.2.
:
import java.awt.*;
public class Quest2 extends Frame{
Quest2(){
Button yes = new Button("YES");
Button no = new Button("NO");
add(yes);
add(no);
setSize(100, 100);
setVisible(true);
}
public static void main(String[] args){
Quest2 q = new Quest2();
} }
:
1) , , YES NO ;
2) YES, ;
3) NO, ;
4) YES NO.
13.3.
FlowLayout?
1) FlowLayout.RIGHT;
2) FlowLayout.LEFT;
3) FlowLayout.CENTER;
4) FlowLayout.LEADING;
5) .
13.4.
?
import java.awt.*; public class Quest4 extends java.applet.Applet{ Button b = new Button("YES"); public void init(){ add(b); add(b); add(new Button("NO")); add(new Button("NO")); }}1) YES NO;
2) YES NO;
3) YES NO;
4) YES NO.
13.5.
JheckBox :
JCheckBox ob = new JCheckBox();
?
1) ob.addItemListener();
2) ob.addItemListener(this);
3) addItemListener(this);
4) addItemListener();
5) .
Thread Runnable
(Rich Client)
Web- (Thin Client) , , . , , . , , ( ) . : Thread Runnable.
// # 1: Thread: Talk.java
package chapt14;
public class Talk extends Thread {
public void run() {
for (int i = 0; i < 8; i++) {
System. out. println("Talking");
try {
// 400
Thread. sleep (400);
} catch (InterruptedException e) {
System. err. print(e);
}
}
}
}
Runnable run(). :
/* # 2: Runnable: Walk.java: WalkTalk.java */
package chapt14;
public class Walk implements Runnable {
public void run() {
for (int i = 0; i < 8; i++) {
System. out. println("Walking");
try {
Thread. sleep (400);
} catch (InterruptedException e) {
System. err. println(e);
}
}
}
}
package chapt14;
public class WalkTalk {
public static void main(String[] args) {
//
Talk talk = new Talk();
Thread walk = new Thread(new Walk());
//
talk.start();
walk.start();
//Walk w = new Walk(); // ,
|
|
|
// w.run(); // , !
}
}
Talk Walk
: Talking Walking. , , .
Thread : , , . (NEW) . (RUNNABLE) start(), run() .
. 14.1.
, Thread.State:
NEW , ;
RUNNABLE ;
BLOCKED ;
WAITING ;
TIMED_WAITING ;
TERMINATED .
getState().
(WAITING) wait(), suspend() (deprecated-) /, . ( ) (TIMED_WAITING) sleep(long millis) wait(long timeout), InterruptedException. suspend() resume() (deprecated-), wait() notify() notifyAll(). (TERMINATED), interrupt(), stop() (deprecated-) run() . , , . interrupt() , . , .
Runnable start(), run(). , Walk, Thread Walk . run() , .
suspend(), resume() stop() deprecated- , -
.
1 ( MIN_PRIORITY) 10 (MAX_PRIORITY) setPriority(int prior). getPriority().
// # 3: : PriorityRunner.java: PriorThread.java
package chapt14;
public class PriorThread extends Thread {
public PriorThread(String name){
super (name);
}
public void run(){
for (int i = 0; i < 71; i++){
System. out. println(getName() + " " + i);
try {
sleep (1); // sleep(0);
} catch (InterruptedException e) {
System. err. print("Error" + e);
}
}
}
}
package chapt14;
public class PriorityRunner {
public static void main(String[] args) {
PriorThread min = new PriorThread("Min"); //1
PriorThread max = new PriorThread("Max"); //10
PriorThread norm = new PriorThread("Norm"); //5
|
|
|
min.setPriority(Thread.MIN_PRIORITY);
max.setPriority(Thread.MAX_PRIORITY);
norm.setPriority(Thread.NORM_PRIORITY);
min.start();
norm.start();
max.start();
}
}
, , .
. .
ThreadGroup tg = new ThreadGroup(" 1");
Thread t0 = new Thread(tg, " 0");
, , . , ,
getThreadGroup(). , . , , .
() sleep( ) Thread. yield(), . join() , , , .
// # 4: : JoinRunner.java
package chapt14;
class Th extends Thread {
public Th(String str) {
super ();
setName(str);
}
public void run() {
String nameT = getName();
System. out. println(" " + nameT);
if ("First".equals(nameT)) {
try {
sleep (5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System. out. println(" "
+ nameT);
} else if ("Second".equals(nameT)) {
try {
sleep (1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
System. out. println(" "
+ nameT);
}
}
}
public class JoinRunner {
public static void main(String[] args) {
Th tr1 = new Th("First");
Th tr2 = new Th("Second");
tr1.start();
tr2.start();
try {
tr1.join();
System. out. println(" main");
} catch (InterruptedException e){
e.printStackTrace();
}
/* join() main tr1 */
}
}
, :
First
Second
Second
First
main
join() tr1, tr2 , main, tr1.
yield() , . , .
// # 5: : YieldRunner.java
package chapt14;
public class YieldRunner {
public static void main(String[] args) {
new Thread() {
public void run() {
System. out. println(" 1");
Thread. yield ();
System. out. println(" 1");
}
}.start();
new Thread() {
public void run() {
System. out. println(" 2");
System. out. println(" 2");
}
}.start();
}
}
:
1
2
2
1
yield() run() , , , , .
-
- , . - , -. setDaemon(boolean value), , -. boolean isDaemon() , .
/* # 6: -: DemoDaemonThread.java */
package chapt14;
|
|
|
class T extends Thread {
public void run() {
try {
if (isDaemon()){
System. out. println(" -");
sleep (10000); // 1
} else {
System. out. println(" ");
}
} catch (InterruptedException e) {
System. err. print("Error" + e);
} finally {
if (!isDaemon())
System. out. println(
" ");
Else
System. out. println(
" -");
}
}
}
package chapt14;
public class DemoDaemonThread {
public static void main(String[] args) {
T usual = new T();
T daemon = new T();
daemon.setDaemon(true);
daemon.start();
usual.start();
System. out. println(
" main");
}
}
, , :
main
-
- (- sleep(10000)) , main(). - - ( ) main(), , - . -, .
. , , , , .
repaint() , . paint() .
/* # 7: : GraphicThreadsDemo.java */
package chapt14;
import java.awt.Color;
import java.awt.Container;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class GraphicThreadsDemo extends JFrame {
JPanel panel = new JPanel();
Graphics g;
JButton btn = new JButton(" ");
int i;
public GraphicThreadsDemo() {
setBounds(100, 200, 270, 350);
Container contentPane = getContentPane();
contentPane.setLayout(null);
btn.setBounds(50, 10, 160, 20);
contentPane.add(btn);
panel.setBounds(30, 40, 200, 200);
panel.setBackground(Color.WHITE);
contentPane.add(panel);
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent ev) {
new BallThread(panel).start();
i++;
repaint();
}
});
}
public static void main(String[] args) {
GraphicThreadsDemo frame =
new GraphicThreadsDemo();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public void paint(Graphics g){
super. paint(g);
g.drawString(" : " + i, 65, 300);
}
}
class BallThread extends Thread {
JPanel panel;
private int posX, posY;
private final int BALL_SIZE = 10;
private double alpha;
private int SPEED = 4;
BallThread(JPanel p) {
this. panel = p;
//
posX = (int)((panel.getWidth() - BALL_SIZE)
* Math.random());
posY = (int)((panel.getHeight() - BALL_SIZE)
* Math.random());
alpha = Math.random() * 10;
}
public void run() {
while (true) {
posX += (int)(SPEED * Math.cos(alpha));
posY += (int)(SPEED * Math.sin(alpha));
//
if (posX >= panel.getWidth() - BALL_SIZE)
alpha = alpha + Math.PI - 2 * alpha;
else if (posX <= 0)
alpha = Math.PI - alpha;
if (posY >= panel.getHeight() - BALL_SIZE)
alpha = -alpha;
else if (posY <= 0)
alpha = -alpha;
paint(panel.getGraphics());
}
}
public void paint(Graphics g) {
//
g.setColor(Color.BLACK);
g.fillArc(posX, posY, BALL_SIZE, BALL_SIZE, 0, 360);
g.setColor(Color.WHITE);
g.drawArc(posX + 1, posY + 1, BALL_SIZE,
BALL_SIZE, 120, 30);
try {
sleep(30);
} catch (InterruptedException e) {
e.printStackTrace();
}
//
g.setColor(panel.getBackground());
g.fillArc(posX, posY, BALL_SIZE, BALL_SIZE, 0, 360);
}
}
.14.2.
stop() , null . start() .
synchronized
, , , ; , . , //. synchronized. /, 32 .
. main() a SynchroThreads . Synchro, FileWriter, . Synchro . writing() Synchro. Synchro. synchronized. , . , . wait() .
.
/* # 8: : MyThread.java: Synchro.java: SynchroThreads.java */
package chapt14;
import java.io.*;
public class Synchro {
private FileWriter fileWriter;
public Synchro(String file) throws IOException {
fileWriter = new FileWriter(file, true);
}
public void close() {
try {
fileWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
}
public synchronized void writing(String str, int i) {
try {
System. out. print(str + i);
fileWriter.append(str + i);
Thread. sleep ((long)(Math. random () * 50));
System. out. print("->" + i + " ");
fileWriter.append("->" + i + " ");
} catch (IOException e) {
System. err. print(" ");
e.printStackTrace();
} catch (InterruptedException e) {
System. err. print(" ");
e.printStackTrace();
}
}
}
package chapt14;
public class MyThread extends Thread {
private Synchro s;
public MyThread(String str, Synchro s) {
super (str);
this. s = s;
}
public void run() {
for (int i = 0; i < 5; i++) {
s.writing(getName(), i);
}
}
}
package chapt14;
import java.io.*;
public class SynchroThreads {
public static void main(String[] args) {
try {
Synchro s = new Synchro("c:\\temp\\data.txt");
MyThread t1 = new MyThread("First", s);
MyThread t2 = new MyThread("Second", s);
t1.start();
t2.start();
t1.join();
t2.join();
s.close();
} catch (IOException e) {
System. err. print(" ");
e.printStackTrace();
} catch (InterruptedException e) {
System. err. print(" ");
e.printStackTrace();
}
}
}
:
First0->0 Second0->0 First1->1 Second1->1 First2->2
Second2->2 First3->3 Second3->3 First4->4 Second4->4
, writing() , , , .
, , :
First0Second0->0 Second1->0 First1->1 First2->1 Second2->2 First3->3 First4->2 Second3->3 Second4->4 ->4
synchronized
-
, . , synchronized,
. , .
/* # 9: : TwoThread.java */
package chapt14;
public class TwoThread {
public static void main(String args[]) {
final StringBuffer s = new StringBuffer();
new Thread() {
public void run() {
int i = 0;
synchronized (s) {
while (i++ < 3) {
s.append("A");
try {
sleep (100);
} catch (InterruptedException e) {
System. err. print(e);
}
System. out. println(s);
}
} // synchronized
}
}.start();
new Thread() {
public void run() {
int j = 0;
synchronized (s) {
while (j++ < 3) {
s.append("B");
System. out. println(s);
}
} // synchronized
}
}.start();
}
}
, ( ), :
A
AA
AAA
AAAB
AAABB
AAABBB
, , , , .
s, , , .
wait()
notify() synchronized . , .
wait(), , , lock. notify()
notifyAll() . , , , .
/* # 10: wait() notify(): Blocked.java: Runner.java */
package chapt14;
public class Blocked {
private int i = 1000;
public int getI() {
return i;
}
public void setI(int i) {
this. i = i;
}
public synchronized void doWait() {
try {
System. out. print(" ");
this. wait(); /*
*/
System. out. print(" "); //
Thread. sleep (50);
} catch (InterruptedException e) {
e.printStackTrace();
}
for (int j = 0; j < 5; j++) i/=5;
System. out. print(" ");
}
}
package chapt14;
public class Runner {
public static void main(String[] args) {
Blocked lock = new Blocked();
new Thread() {
public void run() {
lock.doWait();
}}.start();
try {
Thread. sleep (500);
} catch (InterruptedException e) {
e.printStackTrace();
}
synchronized (lock) { // 1
lock.setI(lock.getI() + 2);
System. out. print(" ");
lock.notify(); //
}
synchronized (lock) { // 2
lock.setI(lock.getI() + 3);
// doWait()
System. out. print(". ");
try {
lock.wait(500);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System. out. print("=" + lock.getI());
}
}
:
. =3
sleep() , . , wait() notify(), :
. =1005
Thread State, , , .
/* # 11: NEW, RUNNABLE, TIMED_WAITING, TERMINATED: ThreadTimedWaitingStateTest.java */
package chapt14;
public class ThreadTimedWaitingStateTest extends Thread {
public void run() {
try {
Thread. sleep (50);
} catch (InterruptedException e) {
System. err. print(" ");
}
}
public static void main(String [] args){
try {
Thread thread = new ThreadTimedWaitingStateTest();
// NEW ,
System. out. println("1: " + thread.getState());
thread.start();
// RUNNABLE
System. out. println("2: " + thread.getState());
Thread.sleep(10);
// TIMED_WAITING
//
System.out.println("3: " + thread.getState());
thread.join();
// TERMINATED
System.out.println("4: " + thread.getState());
} catch (InterruptedException e) {
System.err.print(" ");
}
}
}
:
NEW
RUNNABLE
TIMED_WAITING
TERMINATED
/* # 12: BLOCKED, WAITING: ThreadWaitingStateTest.java */
package chapt14;
public class ThreadWaitingStateTest extends Thread {
public void run() {
try {
synchronized (this) {
wait();
}
} catch (InterruptedException e) {
System.err.print(" ");
}
}
public static void main(String[] args) {
try {
Thread thread = new ThreadWaitingStateTest();
thread.start();
synchronized (thread) {
Thread.sleep(10);
// BLOCKED because thread attempting to acquire a lock
System.out.println("1: " + thread.getState());
}
Thread.sleep(10);
// WAITING wait() synchronized
//
System.out.println("2: " + thread.getState());
thread.interrupt();
} catch (InterruptedException e) {
System.err.print(" ");
}
}
}
:
BLOCKED
WAITING
J2SE 5
Java : . : .
1.5 java.util.concurrent.locks, java.util.concurrent.atomic, java.util.concurrent, , , (concurrent) , , , atomic-.
. , , . , , Hashtable, , ( ) . , .
(thread safe) java.util.concurrent. :
ArrayBlockingQueue (FIFO ), PriorityBlockingQueue ( ) ConcurrentLinkedQueue (FIFO );
- ConcurrentHashMap ( Hashtable)
CopyOnWriteArrayList ( List, , );
, Executor, ;
Lock, , , Condition;
(AtomicInteger, AtomicLong,
AtomicReference), SyncronizedInt .;
, Semaphore, CountDownLatch ( ), CyclicBarrier ( , - ) Exchanger ( );
: Thread ( ThreadGroup).
Hashtable. Hashtable , . ConcurrentHashMap , , . ( ), .
( ) , ConcurrentHashMap Hashtable. Linux. .
| ConcurrentHashMap | Hashtable | |
| 1.00 | 1.03 | |
| 2.59 | 32.40 | |
| 5.58 | 78.23 | |
| 13.21 | 163.48 | |
| 27.58 | 341.21 | |
| 57.27 | 778.41 |
// # 13: : Sort.java: ArraySort.java
package chapt14;
import java.util.concurrent.*;
public class Sort {
public static final int ITEMS_COUNT = 15;
public static double items [];
// ,
public static Semaphore sortSemaphore =
new Semaphore(0, true);
public static void main(String[] args) {
items = new double [ ITEMS_COUNT ];
for (int i = 0; i < items.length; ++i)
items [i] = Math. random ();
new Thread(new ArraySort(items)).start();
for (int i = 0; i < items. length; ++i) {
/*
*
*
*
*/
sortSemaphore. acquireUninterruptibly();
System. out. println(items [i]);
}
}
}
class ArraySort implements Runnable {
private double items[];
public ArraySort(double items[]) {
this. items = items;
}
public void run(){
for (int i = 0; i < items.length - 1; ++i) {
for (int j = i + 1; j < items.length; ++j) {
if (items[i] < items[j]) {
double tmp = items[i];
items[i] = items[j];
items[j] = tmp;
}
}
//
Sort. sortSemaphore. release();
try {
Thread. sleep (71);
} catch (InterruptedException e) {
System. err. print(e);
}
}
Sort. sortSemaphore. release();
}
}
14
1. C : , .
2. C : . .
3. , , , .
4. , 3.
5. , . .
6. , ( ) . , () y, , .. . .
7. ,
. .
8. , .
9. C , .
.
10. .
( , ).
11. .
B
4 (). .
14
14.1.
:
class Q implements Runnable{
int i = 0;
public int run(){
System.out.println("i = "+ ++i);
return i;
}}
public class Quest1 {
public static void main(String[] args) {
Q ob = new Q();
ob.run();
}}
:
1) i = 0;
2) i = 1;
3) : Thread ;
4) : run();
5) : start().
14.2.
:
Thread t1= new Thread();
t1.setPriority(7);
ThreadGroup tg= new ThreadGroup("TG");
tg.setMaxPriority(8);
Thread t2= new Thread(tg,"t2");
System.out.print(" t1="
+ t1.getPriority());
System.out.print(", t2="
+ t2.getPriority());
:
1) t1 = 7, t2 = 5;
2) t1 = 7, t2 = 8;
3) t1 = 10, t2 = 8;
4) .
14.3.
:
class T1 implements Runnable{
public void run(){
System.out.print("t1 ");
} }
class T2 extends Thread{
public void run(){
System.out.print("t2 ");
} }
public class Quest3 {
public static void main(String[] args) {
T1 t1 = new T1();
T2 t2 = new T2(t1);
t1.start();
t2.start();
} }
:
1) t1 t2;
2) t2 t1;
3) : start() T1;
4) : T2 , Thread;
5) .
14.4.
, ? ( )
1) sleep() ;
2) stop();
3) run();
4) notifyAll();
5) wait() null.
14.5.
:
class Quest5 extends Thread {Quest5 () { }Quest5 (Runnable r) { super(r); } public void run() { System.out.print("thread "); } public static void main(String[] args) { Runnable r = new Quest5(); //1Quest5 t = new Quest5(r); //2 t.start(); } }:
1) //1;2) //2;3) thread;4) thread thread; 5) , .
Java . java.net. . . Internet-, Web-, e-mail, , . , , TCP/IP, UDP.
/ , -, -. - , . . , . . , .
TCP/IP :
HTTP - Hypertext Transfer Protocol (WWW);
NNTP - Network News Transfer Protocol ( );
SMTP - Simple Mail Transfer Protocol ( );
POP3 - Post Office Protocol ( );
FTP - File Transfer Protocol ( ).
TCP/IP IP-, . 32- , , , 0 255. IP- , . IP- . Internet IP- (: www.bsu.by), . DNS (Domain Name Server), , IP-. , IP- 127.0.0.1 localhost. IP- , 217.21.43.10:443. 443. 1 1024 , , , : 20 FTP -, 21 FTP -, 53 DNS, 80 HTTP, 25 SMTP, 110 POP3, 119 NNTP. . .
Internet URL. URL (Universal Resource Locator) (http, https, ftp ..) URI (Universal Resource Identifier). URI Internet-, , , :
http://www.bsu.by
URI , , , . . : %20 . : & , ? , + , # (_#_).
IP- InetAddress java.net.
InetAddress public -. . : 2016-04-03; !; : 675 | :
| 1614 - 