java中的接口是类吗
304
2022-08-27
自定义注解+Spel实现分布式锁方式
自定义注解+Spel实现分布式锁方式
目录自定义注解+Spel实现分布式锁依赖RedisLockRegistryConfig自定义注解自定义切面测试类执行结果基于注解的方式实现分布式锁redis分布式锁的实现测试
自定义注解+Spel实现分布式锁
依赖
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> http://
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
http://
RedisLockRegistryConfig
package com.example.demo.config;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.integration.redis.util.RedisLockRegistry;
@Configuration
public class RedisLockRegistryConfig {
/**
* 默认过期时间300s
*/
@Value("${distribute.lock.expireTime:300}")
private long expireTime;
@Value("${spring.application.name:'distributeLock'}")
private String registryKey;
@Bean
public RedisLockRegistry redisLockRegistry(RedisConnectionFactory factory){
return new RedisLockRegistry(factory, registryKey, expireTime * 1000);
}
}
自定义注解
package com.example.demo.aop.annotation;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface DistributeLock {
String name() default "";
}
自定义切面
package com.example.demo.aop;
import com.example.demo.aop.annotation.DistributeLock;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.DefaultParameterNameDiscoverer;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.annotation.Order;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.Expression;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import org.springframework.integration.redis.util.RedisLockRegistry;
import org.springframework.stereotype.Component;
import java.lang.reflect.Method;
import java.util.Objects;
import java.util.concurrent.locks.Lock;
@Aspect
@Order
@Component
public class DistributeLockAop {
private static final Logger LOGGER = LoggerFactory.getLogger(DistributeLockAop.class);
private static SpelExpressionParser parser = new SpelExpressionParser();
private static DefaultParameterNameDiscoverer discoverer = new DefaultParameterNameDiscoverer();
private RedisLockRegistry redisLockRegistry;
public DistributeLockAop(RedisLockRegistry redisLockRegistry) {
this.redisLockRegistry = redisLockRegistry;
}
@Around("@annotation(com.example.demo.aop.annotation.DistributeLock)")
public Object around(ProceedingJoinPoint joinPoint) throws Throwable {
Class> clazz = joinPoint.getTarget().getClass();
MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();
Method method = clazz.getDeclaredMethod(methodSignature.getName(), methodSignature.getParameterTypes());
DistributeLock distributeLock = AnnotationUtils.findAnnotation(method, DistributeLock.class);
assert distributeLock != null;
String spel = distributeLock.name();
String lockName = generateKeyBySpEL(spel, method, joinPoint.getArgs());
Lock lock = redisLockRegistry.obtain(lockName);
if (lock.tryLock()) {
LOGGER.info("DistributeLock locked Success. key:{}", lockName);
return joinPoint.proceed();
} else {
LOGGER.error("DistributeLock locked Failure. key:{}", lockName);
throw new Exception("Lock failure");
}
}
public static String generateKeyBySpEL(String spELString, Method method, Object[] args) {
String[] paramNames = discoverer.getParameterNames(method);
Expression expression = parser.parseExpression(spELString);
EvaluationContext context = new StandardEvaluationContext();
for (int i = 0; i < args.length; i++) {
assert paramNames != null;
context.setVariable(paramNames[i], args[i]);
}
return Objects.requireNonNull(expression.getValue(context)).toString();
}
}
测试类
package com.example.demo.base;
import com.example.demo.aop.annotation.DistributeLock;
import org.springframework.stereotype.Service;
@Service
public class SomeService {
@DistributeLock(name = "'lock:' + #something.name")
public void doSomething(Something something) {
}
}
package com.example.demo.base;
public class Something {
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
package com.example.demo;
UKITlDSgIvimport com.example.demo.base.Something;
import com.example.demo.base.SomeService;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;
@SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(DemoApplication.class, args);
SomeService someService = context.getBean("someService", SomeService.class);
Something something = new Something();
something.setName("gogogo");
someService.doSomething(something);
}
}
执行结果
. ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v2.4.4)
2021-03-25 16:27:49.638 INFO 10492 --- [ main] com.example.demo.DemoApplication : Starting DemoApplication using Java 1.8.0_141 on P80320948 with PID 10492 (D:\workspace\demo\target\classes started by 80320948 in D:\workspace\demo)2021-03-25 16:27:49.641 INFO 10492 --- [ main] com.example.demo.DemoApplication : No active profile set, falling back to default profiles: default2021-03-25 16:27:50.006 INFO 10492 --- [ main] .s.d.r.c.RepositoryConfigurationDelegate : Multiple Spring Data modules found, entering strict repository configuration mode!2021-03-25 16:27:50.008 INFO 10492 --- [ main] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data Redis repositories in DEFAULT mode.2021-03-25 16:27:50.028 INFO 10492 --- [ main] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 6 ms. Found 0 Redis repository interfaces.2021-03-25 16:27:50.144 INFO 10492 --- [ main] faultConfiguringBeanFactoryPostProcessor : No bean named 'errorChannel' has been explicitly defined. Therefore, a default PublishSubscribeChannel will be created.2021-03-25 16:27:50.153 INFO 10492 --- [ main] faultConfiguringBeanFactoryPostProcessor : No bean named 'taskScheduler' has been explicitly defined. Therefore, a default ThreadPoolTaskScheduler will be created.2021-03-25 16:27:50.156 INFO 10492 --- [ main] faultConfiguringBeanFactoryPostProcessor : No bean named 'integrationHeaderChannelRegistry' has been explicitly defined. Therefore, a default DefaultHeaderChannelRegistry will be created.2021-03-25 16:27:50.253 INFO 10492 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.integration.config.IntegrationManagementConfiguration' of type [org.springframework.integration.config.IntegrationManagementConfiguration] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)2021-03-25 16:27:50.329 INFO 10492 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'integrationChannelResolver' of type [org.springframework.integration.support.channel.BeanFactoryChannelResolver] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)2021-03-25 16:27:50.330 INFO 10492 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'integrationDisposableAutoCreatedBeans' of type [org.springframework.integration.config.annotation.Disposables] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)2021-03-25 16:27:50.832 INFO 10492 --- [ main] o.s.s.c.ThreadPoolTaskScheduler : Initializing ExecutorService 'taskScheduler'2021-03-25 16:27:50.872 INFO 10492 --- [ main] o.s.i.endpoint.EventDrivenConsumer : Adding {logging-channel-adapter:_org.springframework.integration.errorLogger} as a subscriber to the 'errorChannel' channel2021-03-25 16:27:50.872 INFO 10492 --- [ main] o.s.i.channel.PublishSubscribeChannel : Channel 'demo.errorChannel' has 1 subscriber(s).2021-03-25 16:27:50.872 INFO 10492 --- [ main] o.s.i.endpoint.EventDrivenConsumer : started bean '_org.springframework.integration.errorLogger'2021-03-25 16:27:50.878 INFO 10492 --- [ main] com.example.demo.DemoApplication : Started DemoApplication in 1.756 seconds (JVM running for 2.569)2021-03-25 16:27:51.545 INFO 10492 --- [ main] com.example.demo.aop.DistributeLockAop : DistributeLock locked Success. key:lock:gogogo
基于注解的方式实现分布式锁
分布式锁的实现有两种方法
基于redis基于zookeeper
为了方便分布式锁的使用, 基于注解的方式抽取成公用组件
DisLock注解
/**
* 分布式锁的注解, 通过指定key作为分布式锁的key
*
* @author wang.js on 2019/1/29.
* @version 1.0
*/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface DisLock {
/**
* 分布式锁的key
*
* @return
*/
String key();
/**
* 分布式锁用的业务场景id
*
* @return
*/
String biz();
/**
* 过期时间, 默认是5秒
* 单位是秒
*
* @return
*/
int expireTime() default 5;
}
处理DisLock的切面
/**
* 处理@DisLock注解的切面
*
* @author wang.js on 2019/1/29.
* @version 1.0
*/
@Aspect
@Order(value = 1)
@Component
public class DisLockAspect {
@Resource
private DisLockUtil disLockUtil;
private static final int MIN_EXPIRE_TIME = 3;
@Around(value = "@annotation(disLock)")
public Object execute(ProceedingJoinPoint proceedingJoinPoint, DisLock disLock) throws Throwable {
int expireTIme = disLock.expireTime() < MIN_EXPIRE_TIME ? MIN_EXPIRE_TIME : disLock.expireTime();
String disKey = CacheKeyParser.parse(proceedingJoinPoint, disLock.key(), disLock.biz());
boolean lock = disLockUtil.lock(disKey, expireTIme);
int count = 1;
while (!lock && count < MIN_EXPIRE_TIME) {
lock = disLockUtil.lock(disKey, expireTIme);
count++;
TimeUnit.SECONDS.sleep(1);
}
Object proceed;
if (lock) {
// 允许查询
try {
proceed = proceedingJoinPoint.proceed();
} finally {
// 删除分布式锁
disLockUtil.unlock(disKey, false);
}
} else {
throw new CustomException(ErrorCodeEnum.DUPLICATE_REQUEST.getMessage());
}
return proceed;
}
}
redis的配置
/**
* @author wang.js
* @date 2018/12/17
* @copyright yougou.com
*/
@Configuration
public class RedisConfig {
@Value("${spring.redis.host}")
private String host;
@Value("${spring.redis.port:6379}")
private Integer port;
@Bean
public JedisPool jedisPool() {
//1.设置连接池的配置对象
JedisPoolConfig config = new JedisPoolConfig();
//设置池中最大连接数
config.setMaxTotal(50);
//设置空闲时池中保有的最大连接数
config.setMaxIdle(10);
config.setMaxWaitMillis(3000L);
config.setTestOnBorrow(true);
//2.设置连接池对象
return new JedisPool(config,host,port);
}
}
redis分布式锁的实现
/**
* redis分布式锁的实现
*
* @author wang.js
* @date 2018/12/18
* @copyright yougou.com
*/
@Component
public class DisLockUtil {
@Resource
private JedisPool jedisPool;
private static final int DEFAULT_EXPIRE_TIME = 5;
private static final Long RELEASE_SUCCESS = 1L;
private static final String LOCK_SUCCESS = "OK";
private static final String SET_IF_NOT_EXIST = "NX";
private static final String SET_WITH_EXPIRE_TIME = "PX";
/**
* 尝试获取分布式锁
*
* @param jedis Redis客户端
* @param lockKey 锁
* @param requestId 请求标识
* @param expireTime 超期时间
* @return 是否获取成功
*/
public static boolean tryGetDistributedLock(Jedis jedis, String lockKey, String requestId, int expireTime) {
String result = jedis.set(lockKey, requestId, SET_IF_NOT_EXIST, SET_WITH_EXPIRE_TIME, expireTime);
if (LOCK_SUCCESS.equals(result)) {
return true;
}
return false;
}
/**
* 释放分布式锁
*
* @param jedis Redis客户端
* @param lockKey 锁
* @param requestId 请求标识
* @return 是否释放成功
*/
public static boolean releaseDistributedLock(Jedis jedis, String lockKey, String requestId) {
String script = "if redis.call('get', KEYS[1]) == ARGV[1] then return redis.call('del', KEYS[1]) else return 0 end";
Object result = jedis.eval(script, Collections.singletonList(lockKey), Collections.singletonList(requestId));
if (RELEASE_SUCCESS.equals(result)) {
return true;
}
return false;
}
/**
* 释放锁
*
* @param key
* @return
*/
public final boolean unlock(String key, boolean needCheck) {
boolean result = false;
Jedis jedis = jedisPool.getResource();
try {
if (needCheck) {
String expireTimeCache = jedis.get(key);
// 判断锁是否过期了
if (StringUtils.isBlank(expireTimeCache)) {
result = true;
}
if (System.currentTimeMillis() - Long.parseLong(expireTimeCache) > 0) {
// 直接删除
jedis.del(key);
result = true;
}
} else {
jedis.del(key);
}
} finally {
jedis.close();
}
return result;
}
/**
* 获取分布式锁
*
* @param key
* @param expireSecond
* @return
*/
public final boolean lock(String key, int expireSecond) {
if (StringUtils.isBlank(key)) {
throw new RuntimeException("传入的key为空");
}
expireSecond = expireSecond == 0 ? DEFAULT_EXPIRE_TIME : expireSecond;
// 过期的时候的时间戳
long expireTime = System.currentTimeMillis() + expireSecond * 1000 + 1;
boolean setResult = false;
Jedis jedis = jedisPool.getResource();
try {
if (jedis.setnx(key, String.valueOf(expireTime)) == 1) {
// 说明加锁成功
setResult = true;
}
if (jedis.ttl(key) < 0) {
jedis.expire(key, expireSecond);
}
if (setResult) {
return true;
}
String expireTimeCache = jedis.get(key);
System.out.println(expireTimeCache + "====" + jedis.ttl(key) + ", now:" + System.currentTimeMillis());
// 判断锁是否过期了
if (StringUtils.isNotBlank(expireTimeCache) && System.currentTimeMillis() - Long.parseLong(expireTimeCache) > 0) {
String oldExpireTime = jedis.getSet(key, String.valueOf(expireTime));
if (StringUtils.isNotBlank(oldExpireTime) && oldExpireTime.equals(String.valueOf(expireTime))) {
jedis.expire(key, expireSecond);
setResult = true;
}
}
} finally {
jedis.close();
}
return setResult;
}
}
实现分布式锁的关键是对key的设置, 需要获取实际的参数来设置分布式锁, 这里自定义了解析器
/**
* cache key 的解析器
*
* @author wang.js on 2019/2/27.
* @version 1.0
*/
public class CacheKeyParser {
/**
* 解析缓存的key
*
* @param proceedingJoinPoint 切面
* @param cacheKey 缓存的key
* @param biz 业务
* @return String
* @throws IllegalAccessException 异常
*/
public static String parse(ProceedingJoinPoint proceedingJoinPoint, String cacheKey, String biz) throws IllegalAccessException {
// 解析实际参数的key
String key = cacheKey.replace("#", "");
StringTokenizer stringTokenizer = new StringTokenizer(key, ".");
Map
Object actualKey = null;
while (stringTokenizer.hasMoreTokens()) {
if (actualKey == null) {
actualKey = nameAndValue.get(stringTokenizer.nextToken());
} else {
actualKey = getPropValue(actualKey, stringTokenizer.nextToken());
}
}
return biz + actualKey;
}
/**
* 获取参数Map集合
*
* @param joinPoint 切面
* @return Map
*/
private static Map
Object[] paramValues = joinPoint.getArgs();
String[] paramNames = ((CodeSignature) joinPoint.getSignature()).getParameterNames();
Map
for (int i = 0; i < paramNames.length; i++) {
param.put(paramNames[i], paramValues[i]);
}
return param;
}
/**
* 获取指定参数名的参数值
*
* @param obj
* @param propName
* @return
* @throws IllegalAccessException
*/
public static Object getPropValue(Object obj, String propName) throws IllegalAccessException {
Field[] fields = obj.getClass().getDeclaredFields();
for (Field f : fields) {
if (f.getName().equals(propName)) {
//在反射时能访问私有变量
f.setAccessible(true);
return f.get(obj);
}
}
return null;
}
}
ErrorCodeEnum
public enum ErrorCodeEnum {
SUCCESS("查询成功", "200"),
SERVER_ERROR("服务器异常", "500"),
SECKILL_END("秒杀活动已结束", "250"),
GOODS_KILLED("秒杀成功", "502"),
ERROR_SIGN("签名不合法", "260"),
UPDATE_SUCCESS("更新成功", "0"),
SAVE_SUCCESS("保存成功", "0"),
UPDATE_FAIL("更新失败", "256"),
EMPTY_PARAM("参数为空", "257"),
SAVE_ERROR("保存失败", "262"),
SERVER_TIMEOUT("调用超时", "501"),
USER_NOT_FOUND("找不到用户", "502"),
COUPON_NOT_FOUND("找不到优惠券", "503"),
DUPLICATE("出现重复", "504"),
USER_STATUS_ABNORMAL("用户状态异常", "505"),
NO_TOKEN("无token，请重新登录", "506"),
ERROR_TOKEN("token不合法", "507"),
EMPTY_RESULT("暂无数据", "508"),
DUPLICATE_REQUEST("重复请求", "509"),
;
/**
* 定义的message
*/
private String message;
/**
* 定义的错误码
*/
private String errCode;
ErrorCodeEnum(String message, String errCode) {
this.message = message;
this.errCode = errCode;
}
public String getMessage() {
return message;
}
protected void setMessage(String message) {
this.message = message;
}
public String getErrCode() {
return errCode;
}
protected void setErrCode(String errCode) {
this.errCode = errCode;
}
}
自定义异常CustomException
/**
* @author Eric on 2018/12/24.
* @version 1.0
*/
@Data
@NoArgsConstructor
@AllArgsConstructor
@Accessors(chain = true)
@EqualsAndHashCode(callSuper = true)
public class CustomException extends RuntimeException {
private String message;
}
配置文件
spring:
redis:
host: mini7
port: 6379
测试
定义一个方法, 加上@RedisCache注解, cacheKey的值必须是#实际参数名.属性名的格式, 如果想要成其他的格式可以修改CacheKeyParser中的parse方法
@DisLock(key = "#id", biz = CommonBizConstant.SECOND_KILL)
@Override
public String testRedisCache(String id) {
LOGGER.info("调用方法获取值");
return "大傻逼";
}
在springboot启动类上加上@ComponentScan({“com.eric”})
/**
* @author Eric on 2019/1/26.
* @version 1.0
*/
@SpringBootApplication
@MapperScan("com.eric.base.data.dao")
@ComponentScan({"com.eric"})
@EnableFeignClients
@EnableDiscoveryClient
public class BaseDataApplication {
public static void main(String[] args) {
SpringApplication.run(BaseDataApplication.class, args);
}
}
写个测试类调用上面的方法
/**
* 基础数据
*
* @author wang.js on 2019/2/27.
* @version 1.0
*/
@SpringBootTest
@RunWith(SpringRunner.class)
public class BaseDataTest {
@Resource
private SysDictService sysDictService;
@Test
public void t1() {
for (int i = 0; i < 100; i++) {
sysDictService.testRedisCache("1");
}
}
}
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