有点类似于之前写过的Java实现生产者消费者模式，这里继续来巩固下。首先是使用synchronized方式来实现。
public class Main {
private static volatile int number = 0;
private static final Object object = new Object(); // 对象锁
public static void main(String[] args) {
new Thread(new Runnable() {
@Override
public void run() {
do {
synchronized (object) {
while (number % 2 == 0) {
try {
object.wait();
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System.out.println("odd : " + number++);
object.notifyAll();
}
} while (number < 10);
}
}).start();
new Thread(new Runnable() {
@Override
public void run() {
do {
synchronized (object) {
while (number % 2 != 0) {
try {
object.wait();
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
System.out.println("even : " + number++);
object.notifyAll();
}
} while (number < 10);
}
}).start();
}
}
结果：
使用ReentrantLock实现如下：
public class Main {
private static volatile int number = 0;
private static ReentrantLock lock = new ReentrantLock();
private static Condition oddC = lock.newCondition();
private static Condition evenC = lock.newCondition();
public static void main(String[] args) {
new Thread(new Runnable() {
@Override
public void run() {
do {
lock.lock();
try{
// 同步代码块
while(number % 2 == 0){
// 这里是用while，不使用if，还是为了防止虚假唤醒
oddC.await();
}
System.out.println("odd : " + number++);
evenC.signal();
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
} while (number < 10);
}
}).start();
new Thread(new Runnable() {
@Override
public void run() {
do {
lock.lock();
try{
while(number % 2 != 0){
evenC.await();
}
System.out.println("even : " + number++);
oddC.signal();
} catch (InterruptedException e) {
e.printStackTrace();
} finally {
lock.unlock();
}
} while (number < 10);
}
}).start();
}
}
结果：
References