P150-lock----鎖----那一節
public class ThreadExtend extends Thread {
static int ticket = 0;
static Lock lock = new ReentrantLock();
public void run() {
while (true) {
lock.lock();
if (ticket == 100) {
break;
} else {
try {
Thread.sleep(30);
ticket++;
System.out.println(Thread.currentThread().getName() + "賣票" + ticket);
} catch (Exception e) {
} finally {
lock.unlock();
}
}
}
}
}
---分割線---對比--
public class ThreadExtend extends Thread {
static int ticket = 0;
static Lock lock = new ReentrantLock();
public void run() {
while (true) {
lock.lock();
if (ticket == 100) {
break;
} else {
try {
Thread.sleep(30);
} catch (Exception e) {
} finally {
lock.unlock();
}
ticket++;
System.out.println(Thread.currentThread().getName() + "賣票" + ticket);
}
}
}
}
----------********-----------
ticket++;
sout();
換個位置。結果完全不一樣。這是不是說明 就算加鎖， try裏面的語句會全部執行完畢呢？ 這種隨機性，不會跨越try括號裏的整體？？？