简介
recipes的InterProcessSemaphoreMutex是一种不可重入的互斥锁，也就意味着即使是同一个线程也无法在持有锁的情况下再次获得锁，所以需要注意，不可重入的锁很容易在一些情况导致死锁，比如你写了一个递归。
官方文档：http://curator.apache.org/curator-recipes/shared-lock.html
javaDoc：http://curator.apache.org/curator-recipes/shared-lock.html
代码示例
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.framework.recipes.locks.InterProcessSemaphoreMutex;
import org.apache.curator.retry.ExponentialBackoffRetry; public class SemaphoreMutexDemo {
private static CuratorFramework client = CuratorFrameworkFactory.newClient("localhost:2181", new ExponentialBackoffRetry(3000, 3));
private static String path = "/locks/semaphore/0001";
static {
client.start();
} public static void main(String[] args) throws Exception {
startThread0();
Thread.sleep(10);
startThread1();
Thread.sleep(50000);
client.close();
} private static void startThread0() {
new Thread(() -> {
InterProcessSemaphoreMutex lock = new InterProcessSemaphoreMutex(client, path);
try {
System.out.println("thread0 acquiring");
lock.acquire();
System.out.println("thread0 acquired");
System.out.println("thread0 sleep for 3s");
Thread.sleep(3000);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
lock.release();
System.out.println("thread0 release");
} catch (Exception e) {
e.printStackTrace();
}
}
}).start();
} private static void startThread1() {
new Thread(() -> {
InterProcessSemaphoreMutex lock = new InterProcessSemaphoreMutex(client, path);
try {
System.out.println("thread1 acquiring");
lock.acquire();
System.out.println("thread1 acquired");
System.out.println("thread1 sleep for 3s");
Thread.sleep(3000);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
lock.release();
System.out.println("thread1 release");
} catch (Exception e) {
e.printStackTrace();
}
}
}).start();
}
}