描述

• 基于SpringEL表达式，动态配置
• 基于切面，无缝切入
• 支持获取锁失败时的行为，抛出异常还是继续等待，两种方式的锁，一种等待重试，一种直接退出

https://github.com/shawntime/shawn-common-utils/tree/master/src/main/java/com/shawntime/common/lock

使用方法

@RedisLockable(key = {"#in.activityId", "#in.userMobile"}, expiration = 120, isWaiting = true, retryCount = 2)
@Override
public PlaceOrderOut placeOrder(OrderIn in) {// ------
}

代码实现

package com.shawntime.common.lock;import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/*** RUNTIME* 定义注解* 编译器将把注释记录在类文件中，在运行时 VM 将保留注释，因此可以反射性地读取。* @author shma1664**/
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface RedisLockable {String prefix() default "";String[] key() default "";long expiration() default 120;boolean isWaiting() default false; //锁是否等待，默认为不等待int retryCount() default -1; // 锁等待重试次数，-1未不限制
}

package com.shawntime.common.lock;import java.lang.reflect.Method;
import java.util.concurrent.TimeUnit;import com.google.common.base.Joiner;
import com.shawntime.common.cache.redis.SpringRedisUtils;
import com.shawntime.common.common.spelkey.KeySpELAdviceSupport;
import org.apache.commons.lang3.StringUtils;
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.springframework.aop.support.AopUtils;
import org.springframework.stereotype.Component;/*** Created by IDEA* User: mashaohua* Date: 2016-09-28 18:08* Desc:*/
@Aspect
@Component
public class RedisLockInterceptor extends KeySpELAdviceSupport {@Pointcut("@annotation(com.shawntime.common.lock.RedisLockable)")public void pointcut() {}@Around("pointcut()")public Object doAround(ProceedingJoinPoint point) throws Throwable {MethodSignature methodSignature = (MethodSignature) point.getSignature();Method targetMethod = AopUtils.getMostSpecificMethod(methodSignature.getMethod(), point.getTarget().getClass());String targetName = point.getTarget().getClass().getName();String methodName = point.getSignature().getName();Object target = point.getTarget();Object[] arguments = point.getArgs();RedisLockable redisLock = targetMethod.getAnnotation(RedisLockable.class);long expire = redisLock.expiration();String redisKey = getLockKey(redisLock, targetMethod, targetName, methodName, target, arguments);boolean isLock;if (redisLock.isWaiting()) {isLock = waitingLock(redisKey, expire, redisLock.retryCount());} else {isLock = noWaitingLock(redisKey, expire);}if (isLock) {long startTime = System.currentTimeMillis();try {return point.proceed();} finally {long parseTime = System.currentTimeMillis() - startTime;if (parseTime <= expire * 1000) {unLock(redisKey);}}} else {throw new RuntimeException("您的操作太频繁，请稍后再试");}}private String getLockKey(RedisLockable redisLock, Method targetMethod, String targetName, String methodName,Object target, Object[] arguments) {String[] keys = redisLock.key();String prefix = redisLock.prefix();StringBuilder sb = new StringBuilder("lock.");if (StringUtils.isEmpty(prefix)) {sb.append(targetName).append(".").append(methodName);} else {sb.append(prefix);}if (keys != null) {String keyStr = Joiner.on("+ '.' +").skipNulls().join(keys);SpELOperationContext context = getOperationContext(targetMethod, arguments, target, target.getClass());Object key = generateKey(keyStr, context);sb.append("#").append(key);}return sb.toString();}/*** 加锁** @param key    redis key* @param expire 过期时间，单位秒* @return true:加锁成功，false，加锁失败*/private boolean noWaitingLock(String key, long expire) {long value = System.currentTimeMillis() + expire * 1000;boolean status = SpringRedisUtils.setNX(key, value);if (status) {return true;}long oldExpireTime = SpringRedisUtils.get(key, Long.class);if (oldExpireTime < System.currentTimeMillis()) {//超时long newExpireTime = System.currentTimeMillis() + expire * 1000;Long currentExpireTime = SpringRedisUtils.getSet(key, newExpireTime, Long.class);if (currentExpireTime == null) {return true;}if (currentExpireTime.longValue() == oldExpireTime) {return true;}}return false;}/*** 等待锁** @param key    redis key* @param expire 过期时间，单位秒* @return true:加锁成功，false，加锁失败*/private boolean waitingLock(String key, long expire, int retryCount) {int count = 0;while (retryCount == -1 || count <= retryCount) {if (noWaitingLock(key, expire)) {return true;}try {TimeUnit.MILLISECONDS.sleep(10);} catch (InterruptedException e) {e.printStackTrace();}count++;}return false;}private void unLock(String key) {SpringRedisUtils.delete(key);}}