Java Threads: New features-Atomic weights

The so-called atomic weight is the operation of the variable is "atom", the operation can not be divided, so it is thread-safe.

Why use atomic variables because multiple threads can also cause problems with a single variable operation. Before Java5, you can solve the security problems of concurrent access by volatile, synchronized keywords, but this is too cumbersome.

JAVA5 provides a toolkit java.util.concurrent.atomic for single variable multithreaded concurrency security access, and the classes are simple.

Here is a negative example (do not imitate):

Import Java.util.concurrent.ExecutorService;
Import java.util.concurrent.Executors;
Import Java.util.concurrent.atomic.AtomicLong;
/**
* Java Thread: New feature-Atomic weight
*
* @author Leizhimin
*/
public class Test {
public static void Main (string[] args) {
Executorservice pool = Executors.newfixedthreadpool (2);
Runnable T1 = new Myrunnable ("John", 2000);
Runnable t2 = new Myrunnable ("Dick", 3600);
Runnable t3 = new Myrunnable ("Harry", 2700);
Runnable T4 = new Myrunnable ("Old Zhang", 600);
Runnable T5 = new myrunnable ("Old Ox", 1300);
Runnable T6 = new Myrunnable ("Fatso", 800);
Executing individual threads
Pool.execute (t1);
Pool.execute (T2);
Pool.execute (T3);
Pool.execute (T4);
Pool.execute (T5);
Pool.execute (T6);
Close the thread pool
Pool.shutdown ();
}
}
Class Myrunnable implements Runnable {
private static Atomiclong along = new Atomiclong (10000); Atomic weights, each thread is free to operate
private String name; Operation Person
private int x; Operating Amount
Myrunnable (String name, int x) {
THIS.name = name;
this.x = x;
}
public void Run () {
SYSTEM.OUT.PRINTLN (name + "executes + x +", Current balance: "+ along.addandget (x));"
}
}

Run Result:

李四执行了3600，当前余额：13600
王五执行了2700，当前余额：16300
老张执行了600，当前余额：16900
老牛执行了1300，当前余额：18200
胖子执行了800，当前余额：19000
张三执行了2000，当前余额：21000
Process　finished　with　exit　code　0

张三执行了2000，当前余额：12000
王五执行了2700，当前余额：18300
老张执行了600，当前余额：18900
老牛执行了1300，当前余额：20200
胖子执行了800，当前余额：21000
李四执行了3600，当前余额：15600
Process　finished　with　exit　code　0

张三执行了2000，当前余额：12000
李四执行了3600，当前余额：15600
老张执行了600，当前余额：18900
老牛执行了1300，当前余额：20200
胖子执行了800，当前余额：21000
王五执行了2700，当前余额：18300
Process　finished　with　exit　code　0