案例
10个线程并发累加一个整数，每个线程累加1000，保证线程安全
Unsafe类，来源于sun.misc包。该类封装了许多类似指针操作，可以直接进行内存管理、操纵对象、阻塞/唤醒线程等操作。
package com.jane;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicInteger;
public class Main {
public static void main(String[] args) throws InterruptedException {
AtomicInteger ai = new AtomicInteger();
List list = new ArrayList<>();
for (int i = 0; i < 10; i++) {
Thread t = new Thread(new Accumlator(ai), "thread-" + i);
list.add(t);
t.start();
}
for (Thread t : list) {
t.join();
}
System.out.println(ai);
}
static class Accumlator implements Runnable {
private AtomicInteger ai;
Accumlator(AtomicInteger ai) {
this.ai = ai;
}
@Override
public void run() {
for (int i = 0, len = 1000; i < len; i++) {
ai.incrementAndGet();
}
}
}
}
运行结果
