Redisson是一个在Redis的基础上实现的Java驻内存数据网格。它几乎提供了Redis所有工具,不仅封装Redis底层数据结构,而且还提供了很多Java类型映射。Redisson支持redis单实例、redis哨兵、redis cluster、redis master-slave等各种部署架构。Redisson除了普通分布式锁还支持 联锁(MultiLock),读写锁(ReadWriteLock),公平锁(Fair Lock),红锁(RedLock),信号量(Semaphore),可过期性信号量(PermitExpirableSemaphore)和闭锁(CountDownLatch)等。
Redisson 虽然功能强大但是它依然不能解决分布式锁有可能锁不住的情况,这不是Redisson或者Redis的问题(目前遇到这种问题只能人工干预)。本篇主要是平时工作中使用对Redisson分布式锁的封装
Maven主要包配置
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.6</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
<version>2.1.9.RELEASE</version>
</dependency>
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
<version>2.9.0</version>
</dependency>
<dependency>
<groupId>org.redisson</groupId>
<artifactId>redisson</artifactId>
<version>3.11.2</version>
</dependency>
yml 配置
redis:
server:
database: 0
host: redis的ip地址
maxIdle: 500
maxTotal: 50
maxWaitMillis: 10000
minEvictableIdleTimeMillis: 60000
minIdle: 10
numTestsPerEvictionRun: 10
password: yiwei-redis-666
port: redis的端口号
testOnBorrow: true
testOnReturn: true
testWhileIdle: true
timeBetweenEvictionRunsMillis: 30000
timeOut: 2000
JedisProperties属性配置
import lombok.Data;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
@Data
@Component
public class JedisProperties {
@Value("${redis.server.host}")
private String host;
@Value("${redis.server.port}")
private int port;
@Value("${redis.server.password}")
private String password;
@Value("${redis.server.maxTotal}")
private int maxTotal;
@Value("${redis.server.maxIdle}")
private int maxIdle;
@Value("${redis.server.minIdle}")
private int minIdle;
@Value("${redis.server.maxWaitMillis}")
private int maxWaitMillis;
@Value("${redis.server.timeOut}")
private int timeOut;
@Value("${redis.server.testOnBorrow}")
private boolean testOnBorrow;
@Value("${redis.server.testOnReturn}")
private boolean testOnReturn;
@Value("${redis.server.testWhileIdle}")
private boolean testWhileIdle;
@Value("${redis.server.timeBetweenEvictionRunsMillis}")
private int timeBetweenEvictionRunsMillis;
@Value("${redis.server.numTestsPerEvictionRun}")
private int numTestsPerEvictionRun;
@Value("${redis.server.minEvictableIdleTimeMillis}")
private int minEvictableIdleTimeMillis;
@Value("${redis.server.database}")
private int database;
}
JedisConfig 相关Bean配置
import lombok.extern.slf4j.Slf4j;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisPassword;
import org.springframework.data.redis.connection.RedisStandaloneConfiguration;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import redis.clients.jedis.JedisPoolConfig;
import javax.annotation.Resource;
@Slf4j
@Configuration
@EnableCaching
public class JedisConfig {
@Resource
private JedisProperties prop;
@Bean(name = "jedisPoolConfig")
public JedisPoolConfig jedisPoolConfig() {
JedisPoolConfig config = new JedisPoolConfig();
config.setMaxTotal(prop.getMaxTotal());
config.setMaxIdle(prop.getMaxIdle());
config.setMinIdle(prop.getMinIdle());
config.setMaxWaitMillis(prop.getMaxWaitMillis());
config.setTestOnBorrow(prop.isTestOnBorrow());
config.setTestOnReturn(prop.isTestOnReturn());
config.setTestWhileIdle(prop.isTestWhileIdle());
config.setNumTestsPerEvictionRun(prop.getNumTestsPerEvictionRun());
config.setMinEvictableIdleTimeMillis(prop.getMinEvictableIdleTimeMillis());
config.setTimeBetweenEvictionRunsMillis(prop.getTimeBetweenEvictionRunsMillis());
return config;
}
@Bean(name ="jedisConnectionFactory")
public JedisConnectionFactory jedisConnectionFactory(){
RedisStandaloneConfiguration redisStandaloneConfiguration = new RedisStandaloneConfiguration();
redisStandaloneConfiguration.setPort(prop.getPort());
redisStandaloneConfiguration.setHostName(prop.getHost());
redisStandaloneConfiguration.setPassword(RedisPassword.of(prop.getPassword()));
redisStandaloneConfiguration.setDatabase(prop.getDatabase());
return new JedisConnectionFactory(redisStandaloneConfiguration);
}
@Bean(name ="redisTemplate")
public RedisTemplate<String, Object> redisTemplate(JedisConnectionFactory jedisConnectionFactory) {
RedisTemplate<String, Object> template = new RedisTemplate<>();
template.setConnectionFactory(jedisConnectionFactory);
return template;
}
}
RedissonConfig 配置类
import org.redisson.Redisson;
import org.redisson.api.RedissonClient;
import org.redisson.config.Config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.annotation.Resource;
@Configuration
public class RedissonConfig {
@Resource
private JedisProperties prop;
@Bean
public RedissonClient redissonClient(){
Config config = new Config();
config.useSingleServer().setAddress("redis://" + prop.getHost() + ":" + prop.getPort())
.setPassword(prop.getPassword()).setDatabase(prop.getDatabase());
return Redisson.create(config);
}
}
函数式接口两个
分布式锁主要采用,模板模式,应为它天生就有业务骨架属性。当我们使用1.8以上的JDK时,针对模板模式,使用方简化了很多操作。只是需要注意定义模板方法时要定义成函数接口
public interface VoidHandle {
/**
* 业务处理
*/
void execute();
}
public interface ReturnHandle<T> {
/**
* 业务处理
* @return
*/
T execute();
}
分布式锁模板封装
@Slf4j
@Service
public class RedisLock {
@Autowired
private RedissonClient redissonClient;
/**
* 分布式锁实现
* @param lockName 锁名称
* @param businessId 业务ID
* @param handle 业务处理
*/
@Transactional(rollbackFor = Exception.class)
public void lock(String lockName, Object businessId, VoidHandle handle) {
RLock rLock = getLock(lockName, businessId);
try {
rLock.lock();
log.info("业务ID{},获取锁成功", businessId);
handle.execute();
} finally {
rLock.unlock();
}
}
/**
* 带返回值分布式锁实现
* @param lockName 锁名称
* @param businessId 业务ID
* @param handle 业务处理
* @param <T> 返回值
* @return
*/
@Transactional(rollbackFor = Exception.class)
public <T> T lock(String lockName, Object businessId, ReturnHandle<T> handle) {
RLock rLock = getLock(lockName, businessId);
try {
rLock.lock();
log.info("业务ID{},获取锁成功", businessId);
return handle.execute();
} finally {
rLock.unlock();
}
}
/**
* 分布式锁实现
* @param lockName 锁名称
* @param businessId 业务ID
* @param handle 业务处理
*/
@Transactional(rollbackFor = Exception.class)
public void tryLock(String lockName, Object businessId, VoidHandle handle) {
RLock rLock = getLock(lockName, businessId);
if (!rLock.tryLock()) {
log.info("业务ID{},获取锁失败,返回", businessId);
return;
}
try {
log.info("业务ID{},获取锁成功", businessId);
handle.execute();
} finally {
rLock.unlock();
}
}
/**
* 带返回值分布式锁实现
* @param lockName 锁名称
* @param businessId 业务ID
* @param handle 业务处理
* @param <T> 返回值
* @return
*/
@Transactional(rollbackFor = Exception.class)
public <T> T tryLock(String lockName, Object businessId, ReturnHandle<T> handle) {
RLock rLock = getLock(lockName, businessId);
if (!rLock.tryLock()) {
log.info("业务ID{},获取锁失败,返回null", businessId);
return null;
}
try {
log.info("业务ID{},获取锁成功", businessId);
return handle.execute();
} finally {
rLock.unlock();
}
}
/**
* 分布式锁实现
* @param lockName 锁名称
* @param businessId 业务ID
* @param handle 业务处理
*/
@Transactional(rollbackFor = Exception.class)
public void tryLockException(String lockName, Object businessId, VoidHandle handle) {
RLock rLock = getLock(lockName, businessId);
if (!rLock.tryLock()) {
log.info("业务ID{},获取锁失败,抛异常处理", businessId);
throw new RuntimeException("处理中");
}
try {
log.info("业务ID{},获取锁成功", businessId);
handle.execute();
} finally {
rLock.unlock();
}
}
/**
* 带返回值分布式锁实现
* @param lockName 锁名称
* @param businessId 业务ID
* @param handle 业务处理
* @param <T> 返回值
* @return
*/
@Transactional(rollbackFor = Exception.class)
public <T> T tryLockException(String lockName, Object businessId, ReturnHandle<T> handle) {
RLock rLock = getLock(lockName, businessId);
if (!rLock.tryLock()) {
log.info("业务ID{},获取锁失败,抛异常处理", businessId);
throw new RuntimeException("处理中");
}
try {
log.info("业务ID{},获取锁成功", businessId);
return handle.execute();
} finally {
rLock.unlock();
}
}
/**
* 获取锁
* @param lockName
* @param businessId
* @return
*/
private RLock getLock(String lockName, Object businessId) {
log.info("获取分布式锁lockName:{},businessId:{}", lockName, businessId);
if (StringUtils.isEmpty(lockName)) {
throw new RuntimeException("分布式锁KEY为空");
}
if (StringUtils.isEmpty(businessId)) {
throw new RuntimeException("业务ID为空");
}
String lockKey = lockName + businessId.toString();
return redissonClient.getLock(lockKey);
}
}
使用例子
@Autowired
private RedisLock redisLock;
@Test
public void test() {
redisLock.tryLock("order:pay:", 1, () -> {
// 业务逻辑
});
Boolean payResult = redisLock.tryLock("order:pay:", 2, () -> {
// 业务逻辑
return true;
});
Integer payResult2 = redisLock.tryLock("order:pay:", 2, () -> {
// 业务逻辑
return 0;
});
String payResult3 = redisLock.tryLock("order:pay:", 2, () -> {
// 业务逻辑
return "";
});
}
测试方法没有粘类,不过已经可以看出用起来还是超方便的。