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Spring boot redis distributed lock

When using annotations to implement distributed locks with reference to spring boot redis, it is found that they can not meet the usage requirements.

So I began to fumble to solve the problem.

As follows, value is the key of lock, because the business requirement key is "cancelOrder_123_321" 123 is the order ID,321 is the user ID

@ RedisLock (value = "cancelOrder_# {# order.orderNo} _ # {# memberId}") @ Transactional (rollbackFor = {RuntimeException.class, Exception.class}) public void cancelOrder (Order order, String memberId) {log.info ("user: {}, order number: {} start the cancellation process.", order.getOrderNo (), memberId); String orderNo = order.getOrderNo (); Order updateOrder = new Order (); updateOrder.setOrderNo (orderNo) UpdateOrder.setOrderState (OrderStateEnum.CANCELED.getKey ())

To make a long story short, friends who need to know more will see the blogs of other great gods.

Why can I cancelOrder_# {# order.orderNo} _ # {# memberId} like this?

What's the most important thing here?

Because I parsed the el expression string into a compound. The compound simple point is the List collection, in which there are el expressions and text, which are executed sequentially in for.

The code is as follows:

Aspect class

Private static final OperationExpressionEvaluator evaluator = new OperationExpressionEvaluator (); @ Around ("lockPoint ()") public Object around (ProceedingJoinPoint pjp) throws Throwable {Method method = ((MethodSignature) pjp.getSignature ()) .getMethod (); RedisLock redisLock = method.getAnnotation (RedisLock.class); String key = getKey (redisLock.value (), method,pjp.getArgs (), pjp.getTarget ()); int retryTimes = redisLock.action (). Equals (RedisLock.LockFailAction.CONTINUE)? RedisLock.retryTimes (): 0; boolean lock = redisLockImpl.lock (key,redisLock.keepMills (), retryTimes,redisLock.sleepMills ()); if (! lock) {log.debug ("get lock failed: {}", key); return null;} log.debug ("get lock success: {}", key); try {return pjp.proceed () } catch (Exception e) {log.error ("execute locked method occured an exception", e);} finally {boolean releaseResult = redisLockImpl.releaseLock (key); log.debug ("release lock: {}-{}", key,releaseResult? "success": "failed");} return null;} private String getKey (String key,Method method,Object [] args,Object target) {if (key.length () targetClass, Method method) {/ / AnnotatedElementKey methodKey = new AnnotatedElementKey (method, targetClass); / / Method targetMethod = this.targetMethodCache.get (methodKey); / / if (targetMethod = = null) {Method targetMethod = AopUtils.getMostSpecificMethod (method, targetClass) If (targetMethod = = null) {targetMethod = method;} / / this.targetMethodCache.put (methodKey, targetMethod); / /} return targetMethod;}

ExpressionRootObject class

/ * @ author liuhanling * @ create 2019-01-14 17:04 * @ desc expression rootObject * / public class ExpressionRootObject {/ * method * / private final Method method; / * parameter array * / private final Object [] args; / * Target object * / private final Object target / * Target class * / private final Class targetClass; public ExpressionRootObject (Method method, Object [] args, Object target, Class targetClass) {Assert.notNull (method, "Method is required"); Assert.notNull (targetClass, "targetClass is required"); this.method = method; this.target = target; this.targetClass = targetClass; this.args = args } public Method getMethod () {return this.method;} public String getMethodName () {return this.method.getName ();} public Object [] getArgs () {return this.args;} public Object getTarget () {return this.target;} public Class getTargetClass () {return this.targetClass;}}

[1] reference link (spring boot redis distributed lock) https://my.oschina.net/dengfuwei/blog/1600681

[2] reference link (el expression) https://blog.csdn.net/zhoudaxia/article/details/38174169

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