, thread stream . thread , stream. , , thread, .
, Java.
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, ;
-.
, .
, Object (. 9):
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9
java.lang.Thread. , .
, .
-, - Thread. :
public class MyClass extends Thread.
-, Runnable. , , , Frame, , Applet. Java , Runnable .
public class MyClass extends Frame implements Runnable.
, run().
Thread. , - ', run(). Runnable run() , (this).
, run(). , : Windows run() . run() start() ( !).
- . Runnable. .
ϳ , : , , .. , Thread.
. start():
public void start();
' Thread ' , Runnable, run(), .
run() , . , run() , , ( ) . , , :
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public final boolean isAlive();
. , ' stop():
public final void stop();
. sleep() ( ):
public static void sleep(long ms);
. . suspend() :
public final void suspend();
resume():
public final void resume();
. Thread . .
1) , , 䳿:
2) , Runnable.
3) Thread .
4) start() . , , . start() ᒺ Thread ( new) start() ᒺ:
myThread.start()
start()
MyClass.start()
main(). .
5) run() . run() . ( repaint()) ( sleep()), .
6) stop().
, . , Thread Runnable. run(). ' , , Runnable .
- . Throwable, Exception, Error. 29. .
(exception) , . () Java- , , . , , FileNotFoundException, (throw) - . 쳭 : , , .
ϳ Java- ᒺ-, ᒺ . ᒺ, , ( , ). ᒺ , , .
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. try-catch . , - IOException:
try {
System.in.read(buffer, 0, 255);
...
}
catch (IOException e) {
String err = e.toString();
System.out.println(err);
}
, Java try catch, . , try , catch .
. catch , ᒺ-. IOException, e. ᒺ Java ᒺ. e ᒺ IOException. ᒺ, , . ( toString()).
, ? , . . , , , , , ( , , , . , ).
, , , , . , , , . . ., .
: , .
, . , actionPerformed() :
public void actionPerformed(ActionEvent evt)
{
String arg = evt.getActionCommand();
if ("Check".equals(arg))
{
String str1 = textField1.getText();
String str2 = textField2.getText();
int first = Integer.parseInt(str1);
int second = Integer.parseInt(str2);
String answer = "No";
if (first*first==second || second*second==first)
{ answer = "Yes"; }
displayStr = "Check Square - " + answer;
repaint();
}
}
, . , Check, . NumberFormatException, Java. , :
public void actionPerformed(ActionEvent evt)
{
String arg = evt.getActionCommand();
if ("Check".equals(arg))
{
String str1 = textField1.getText();
String str2 = textField2.getText();
try {
int first = Integer.parseInt(str1);
int second = Integer.parseInt(str2);
String answer = "No";
if (first*first==second || second*second==first)
answer = "Yes";
displayStr = "Check Square - " + answer;
}
catch (NumberFormatException e) {
displayStr = Input format error;
}
repaint();
}
}
, ( ).
first=first/second;
( , ), , ArithmeticException. :
public void actionPerformed(ActionEvent evt)
{
String arg = evt.getActionCommand();
if ("Check".equals(arg))
{
String str1 = textField1.getText();
String str2 = textField2.getText();
try {
int first = Integer.parseInt(str1);
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int second = Integer.parseInt(str2);
String answer = "No";
first = first/second;
if (first*first==second || second*second==first)
answer = "Yes";
displayStr = "Check Square - " + answer;
}
catch (NumberFormatException e) {
displayStr = Input format error;
}
catch (ArithmeticException e) {
displayStr = Division by zero
}
repaint();
}
}
catch , try.
, . :
public int fact(int num) throws IllegalArgumentException
{
if (num < 0 || num>10)
{
throw new IllegalArgumentException(Number out of range);
}
int res=1;
for (int i =1; i<=num; i++)
res*= i;
return res;
}
fact() , , fact():
try {
f = fact(x);
...
}
catch (IllegalArgumentException e) {
displayStr=e.toString();
}
, [2].
ϳ , , : (, IOException, ArithmeticException) throw: , throw new IllegalArgumentException. - try-catch.
