Java AtomicInteger, javaatomicinteger

Java AtomicInteger, javaatomicinteger

AtomicInteger, a class that provides atomic operations. In Java, the ++ I and I ++ operations are not thread-safe. When using them, the synchronized keyword is inevitable. AtomicInteger uses a thread-safe addition/subtraction operation interface.

Import java. text. SimpleDateFormat;

Import java. util. Date;
Import java. util. Timer;
Import java. util. TimerTask;
Import java. util. concurrent. ScheduledThreadPoolExecutor;
Import java. util. concurrent. TimeUnit;
Import java. util. concurrent. atomic. AtomicInteger;




/**
* @ Description
* @ Author
* @ Date 9:37:45
*/
Public class ConcurrentAtomicTest {


Private final static AtomicInteger atomicInteger = new AtomicInteger (1 );
Private static volatile int integer = 1 ;;


/**
* @ Description TODO
* @ Return void
* @ Throws
*/
Public static void main (String [] args ){
// TODO Auto-generated method stub
// TestAtomicInteger ();
TestInteger2 ();


}


Public static void testAtomicInteger (){
String time = new SimpleDateFormat ("HH: mm: ss"). format (new Date ());
System. out. println ("Start time:" + time );

Int temp = atomicInteger. addAndGet (1); // add
AtomicInteger. get (); // get current
System. out. print (temp + ",");

Temp = atomicInteger. decrementAndGet (); // Atomically decrements by one the current value.
System. out. print (temp + ",");

Temp = atomicInteger. getAndIncrement (); // Atomically decrements by one the current value.
System. out. print (temp + ",");

Temp = atomicInteger. intValue (); // Atomically decrements by one the current value.
System. out. print (temp + ",");

AtomicInteger. set (0); // Atomically decrements by one the current value.
Temp = atomicInteger. get ();
System. out. println (temp + ",");

// Result: 2, 1, 2, 0,


ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor (5); // create five execution threads


Runnable runnable = new Runnable (){
@ Override
Public void run (){
String time = new SimpleDateFormat ("HH: mm: ss"). format (new Date ());
AtomicInteger. incrementAndGet ();
System. out. println ("Now Time:" + time + ", integer:" + integer );
}
};


Executor. scheduleWithFixedDelay (runnable, 2, 3, TimeUnit. SECONDS );
}

/**
* Test int plus 1
* @ Description TODO
* @ Return void
* @ Throws
*/
Public static void testInteger2 (){
String time = new SimpleDateFormat ("HH: mm: ss"). format (new Date ());
System. out. println ("Start time:" + time );

Integer ++;
System. out. println ("integer ++:" + integer );

Integer --;
System. out. println ("integer --:" + integer );


ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor (5); // create five execution threads


Runnable runnable = new Runnable (){
@ Override
Public void run (){
String time = new SimpleDateFormat ("HH: mm: ss"). format (new Date ());
Integer = integer + 1;
System. out. println ("Now Time:" + time + ", testInteger2 Integer:" + atomicInteger. get ());
}
};


Executor. scheduleWithFixedDelay (runnable, 2, 3, TimeUnit. SECONDS );
}
// Start time: 10:27:16
// Integer ++: 2
// Integer --: 1
// Now Time: 10:27:18, testInteger2 Integer: 1
// Now Time: 10:27:21, testInteger2 Integer: 1
// Now Time: 10:27:24, testInteger2 Integer: 1
// Now Time: 10:27:27, testInteger2 Integer: 1


}