springboot(十二)分布式锁（redis）

<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>4.0.0modelVersion>

  <groupId>com.itmuch.cloudgroupId>
  <artifactId>redisLockartifactId>
  <version>0.0.1-SNAPSHOTversion>
  <packaging>jarpackaging>

  <name>redisLockname>
  <url>http://maven.apache.orgurl>

  <parent>
        <groupId>org.springframework.bootgroupId>
        <artifactId>spring-boot-starter-parentartifactId>
        <version>2.0.0.RELEASEversion>
   parent>
    <dependencies>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-webartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-starter-tomcatartifactId>
        dependency>
        <dependency>
            <groupId>org.springframework.bootgroupId>
            <artifactId>spring-boot-devtoolsartifactId>
            <optional>trueoptional> 
        dependency>
        <dependency>
              <groupId>org.springframework.bootgroupId>
              <artifactId>spring-boot-starter-integrationartifactId>
        dependency>
        <dependency>
              <groupId>org.springframework.integrationgroupId>
              <artifactId>spring-integration-redisartifactId>
        dependency>
        <dependency>
              <groupId>org.springframework.bootgroupId>
              <artifactId>spring-boot-starter-data-redisartifactId>
        dependency>
    <dependency>
              <groupId>junitgroupId>
              <artifactId>junitartifactId>
              <scope>testscope>
        dependency>
    dependencies>
    <properties>
        <java.version>1.8java.version>
    properties>


    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.bootgroupId>
                <artifactId>spring-boot-maven-pluginartifactId>
            plugin>
        plugins>
    build>

project>

server:
  port: 8080
spring:
  redis:
    port: 6379
    host: localhost

@Configuration
public class RedisLockConfiguration {
  @Bean
  public RedisLockRegistry redisLockRegistry(RedisConnectionFactory redisConnectionFactory) {
    return new RedisLockRegistry(redisConnectionFactory, "spring-cloud");
  }
}

@RestController
@RequestMapping(value = "index")
public class testController {
    private final static Logger log = LoggerFactory.getLogger(testController.class);
    @Autowired
    private RedisLockRegistry redisLockRegistry;
    @GetMapping("test")
    public void test() throws InterruptedException {
      Lock lock = redisLockRegistry.obtain("lock");
      boolean b1 = lock.tryLock(3, TimeUnit.SECONDS);
      log.info("b1 is : {}", b1);

      TimeUnit.SECONDS.sleep(5);

      boolean b2 = lock.tryLock(3, TimeUnit.SECONDS);
      log.info("b2 is : {}", b2);

      lock.unlock();
      lock.unlock();
    }

/**
 * Implementation of {@link LockRegistry} providing a distributed lock using Redis.
 * Locks are stored under the key {@code registryKey:lockKey}. Locks expire after
 * (default 60) seconds. Threads unlocking an
 * expired lock will get an {@link IllegalStateException}. This should be
 * considered as a critical error because it is possible the protected
 * resources were compromised.
 * 

 * Locks are reentrant.
 * 

 * However, locks are scoped by the registry; a lock from a different registry with the
 * same key (even if the registry uses the same 'registryKey') are different
 * locks, and the second cannot be acquired by the same thread while the first is
 * locked.
 * 

 * Note: This is not intended for low latency applications. It is intended
 * for resource locking across multiple JVMs.
 * 

 * {@link Condition}s are not supported.