运行了以后等了好久，500个线程也执行不完是为什么？
package synchronize;
public class VolatileDemo {
private volatile int number = 0;
public int getNumber() {
return this.number;
}
public void increase() {
this.number++;
}
public static void main(String[] args) {
final VolatileDemo vd = new VolatileDemo();
for (int i = 0; i < 500; i++) {
new Thread(() -> vd.increase()).start();
}
while (Thread.activeCount() > 1) {
Thread.yield();
}
System.out.println("number is " + vd.getNumber());
}
}这个代码在idea里面启动了以后，一直不结束是为什么？
