static void testLock1(){ final AtomicInteger waitCount = new AtomicInteger(30000);
final Object waitObj = new Object();
System.out.println("start"+System.currentTimeMillis());
for (int i=0;i<30000;i++) {
new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
waitCount.decrementAndGet();
synchronized(waitObj){
waitObj.notifyAll();
}
}
}).start();
}
while( waitCount.intValue()>0) {
synchronized (waitObj) {
if(waitCount.intValue()>0){
try {
waitObj.wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
System.out.println("ok"+System.currentTimeMillis());
}
static void testLock2(){ final CountDownLatch workLauch = new CountDownLatch(30000);//计数器
System.out.println("start2"+System.currentTimeMillis());
for (int i=0;i<30000;i++) {
new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(10);
} catch (InterruptedException e) {
e.printStackTrace();
}
workLauch.countDown();
}
}).start();
}
try {
workLauch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("ok2"+System.currentTimeMillis());
}
public static void main(String[] args) {
testLock1();
testLock2();
}
第一种是我随便写的实现,有点糙。第二种是朋友告知的一个类,java的concurrent中的,据说还有几个相似功能的类实现。这30000个线程 时间差大概是不到200ms的样子
嗯。。。。吃饭的家伙都没学精,好惭愧。