基于ZooKeeper分布式锁的流程
- 在zookeeper指定节点（locks）下创建临时顺序节点node_n
-
获取locks下所有子节点children
-
对子节点按节点自增序号从小到大排序
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判断本节点是不是第一个子节点，若是，则获取锁；若不是，则监听比该节点小的那个节点的删除事件
- 若监听事件生效，则回到第二步重新进行判断，直到获取到锁
具体实现
添加Maven依赖：
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.falsh</groupId> <artifactId>mytiming</artifactId> <version>1.0-SNAPSHOT</version> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.4.RELEASE</version> <relativePath /> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-quartz</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-aop</artifactId> </dependency> <dependency> <groupId>com.alibaba.spring.boot</groupId> <artifactId>dubbo-spring-boot-starter</artifactId> <version>2.0.0</version> <exclusions> <exclusion> <artifactId>spring-context</artifactId> <groupId>org.springframework</groupId> </exclusion> <exclusion> <artifactId>spring-core</artifactId> <groupId>org.springframework</groupId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.apache.curator</groupId> <artifactId>curator-recipes</artifactId> <version>2.3.0</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-source-plugin</artifactId> <executions> <execution> <id>attach-sources</id> <goals> <goal>jar</goal> </goals> </execution> </executions> </plugin> </plugins> </build> </project>
代码：
package com.falsh.tss.config; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.stereotype.Component; @Component public class CommonEnv { public static String ZK_ADDRESS; public static String ZK_LOCK_PATH; @Autowired public void setZkAddress(@Value("${zk.address}") String zkAddress) { ZK_ADDRESS = zkAddress; } @Autowired public void setZkLockPath(@Value("${zk.lock.path}") String zkLockPath) { ZK_LOCK_PATH = zkLockPath; } }
package com.falsh.tss.global; import org.aspectj.lang.ProceedingJoinPoint; import org.aspectj.lang.annotation.Around; import org.aspectj.lang.annotation.Aspect; import org.aspectj.lang.annotation.Pointcut; import org.aspectj.lang.reflect.MethodSignature; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.stereotype.Component; import com.falsh.tss.mutex.MutexLock; @Aspect @Component public class ControlExecJobAspect { private final Logger logger = LoggerFactory.getLogger(ControlExecJobAspect.class); @Pointcut("execution(public * com.zhifu.tss.jobs..*(..))") public void jobExec() { } @Around("jobExec()") public void doAround(ProceedingJoinPoint pjp) throws Throwable{ String jobClass = pjp.getTarget().getClass().getSimpleName(); String methodName = ((MethodSignature) pjp.getSignature()).getMethod().getName(); if (!MutexLock.isInstantiated() || !MutexLock.getInstance().isAcquiredLock()) { logger.info("-- None lock acquired ! {}.{} --", jobClass, methodName); return; } logger.info("------- start {}.{} --------", jobClass, methodName); long start = System.currentTimeMillis(); try { pjp.proceed(); } catch (Exception e) { logger.error("global erorr occured while {}.{}", jobClass, methodName, e); } long end = System.currentTimeMillis(); logger.info("------- end {}.{}({}ms) --------", jobClass, methodName, end - start); } }
package com.falsh.tss.jobs; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.scheduling.annotation.Scheduled; import org.springframework.stereotype.Component; @Component public class MyJob1 { private final static Logger logger = LoggerFactory.getLogger(MyJob1.class); @Scheduled(cron="${cron.job.myJob1}") public void execute(){ logger.info("我在执行定时任务1....."); try { Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } } }
package com.falsh.tss.mutex; import static com.falsh.tss.config.CommonEnv.ZK_ADDRESS; import static com.falsh.tss.config.CommonEnv.ZK_LOCK_PATH; import org.apache.curator.framework.CuratorFramework; import org.apache.curator.framework.CuratorFrameworkFactory; import org.apache.curator.framework.recipes.locks.InterProcessLock; import org.apache.curator.framework.recipes.locks.InterProcessMutex; import org.apache.curator.retry.RetryNTimes; import org.springframework.beans.factory.DisposableBean; import org.springframework.beans.factory.InitializingBean; public class MutexLock implements InitializingBean, DisposableBean { private static CuratorFramework client; private static InterProcessLock mutexLock; private static volatile boolean acquiredLock; private static volatile MutexLock instance; public MutexLock() { client = CuratorFrameworkFactory.newClient(ZK_ADDRESS, new RetryNTimes(10,5000)); client.start(); mutexLock = new InterProcessMutex(client, ZK_LOCK_PATH); } public static MutexLock getInstance(){ if (instance == null) { synchronized (MutexLock.class) { if (instance == null) {//二次检查 instance = new MutexLock(); } } } return instance; } public static boolean isInstantiated() { if (instance == null) { return false; } return true; } //获取锁 public static void acquireMutexLock() throws Exception { mutexLock.acquire(); acquiredLock = true; } //释放锁 public static void releaseMutexLock() throws Exception { mutexLock.release(); } public static boolean isAcquiredLock() { return acquiredLock; } @Override public void destroy() throws Exception { } @Override public void afterPropertiesSet() throws Exception { } }
package com.falsh.tss; import com.alibaba.dubbo.spring.boot.annotation.EnableDubboConfiguration; import com.falsh.tss.mutex.MutexLock; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.EnableAutoConfiguration; import org.springframework.boot.autoconfigure.SpringBootApplication; import org.springframework.context.annotation.ComponentScan; import org.springframework.scheduling.annotation.EnableScheduling; @EnableScheduling @EnableDubboConfiguration @EnableAutoConfiguration @SpringBootApplication @ComponentScan("com.zhifu") public class Application { private static final Log logger = LogFactory.getLog(Application.class); public static void main(String[] args) { SpringApplication.run(Application.class, args); try { MutexLock.getInstance().acquireMutexLock(); while (true) { logger.warn("锁在我这"); Thread.sleep(60000); } } catch (Exception e) { logger.info("获取锁失败", e); } finally{ try { MutexLock.getInstance().releaseMutexLock(); logger.warn("释放了锁"); } catch (Exception e) { logger.error("释放锁异常", e); } } } }
配置：
application-dev.properties
spring.dubbo.application.name=myjobtss
spring.dubbo.registry.address=zookeeper://192.168.x.x:2181
spring.dubbo.protocol.name=dubbo
cron.job.myJob1=0 0/1 * * * ?
zk.address=192.168.x.x:2181
zk.lock.path=/myjob-quartz-locks