Redisson

1.加锁

private void lock(long leaseTime, TimeUnit unit, boolean interruptibly) throws InterruptedException {
        long threadId = Thread.currentThread().getId();
        Long ttl = this.tryAcquire(leaseTime, unit, threadId);
        //
        if (ttl != null) {
            RFuture<RedissonLockEntry> future = this.subscribe(threadId);
            this.commandExecutor.syncSubscription(future);
            try {
                while(true) {
                    ttl = this.tryAcquire(leaseTime, unit, threadId);
                    if (ttl == null) {
                        return;
                    }
                    if (ttl >= 0L) {
                        try {
                            this.getEntry(threadId).getLatch().tryAcquire(ttl, TimeUnit.MILLISECONDS);
                        } catch (InterruptedException var13) {
                            if (interruptibly) {
                                throw var13;
                            }
                            this.getEntry(threadId).getLatch().tryAcquire(ttl, TimeUnit.MILLISECONDS);
                        }
                    } else if (interruptibly) {
                        this.getEntry(threadId).getLatch().acquire();
                    } else {
                        this.getEntry(threadId).getLatch().acquireUninterruptibly();
                    }
                }
            } finally {
                this.unsubscribe(future, threadId);
            }
        }
    }

  private <T> RFuture<Long> tryAcquireAsync(long leaseTime, TimeUnit unit, long threadId) {
        if (leaseTime != -1) {//设置了过期时间
            return tryLockInnerAsync(leaseTime, unit, threadId, RedisCommands.EVAL_LONG);
        }
        //没设置过期时间默认30s
        RFuture<Long> ttlRemainingFuture = tryLockInnerAsync(commandExecutor.getConnectionManager().getCfg().getLockWatchdogTimeout(), TimeUnit.MILLISECONDS, threadId, RedisCommands.EVAL_LONG);
        ttlRemainingFuture.onComplete((ttlRemaining, e) -> {
            if (e != null) {
                return;
            }
            // lock acquired
            if (ttlRemaining == null) {//开启锁续期延时任务
                scheduleExpirationRenewal(threadId);
            }
        });
        return ttlRemainingFuture;
    }

 private void scheduleExpirationRenewal(long threadId) {
        ExpirationEntry entry = new ExpirationEntry();
        ExpirationEntry oldEntry = EXPIRATION_RENEWAL_MAP.putIfAbsent(getEntryName(), entry);
        if (oldEntry != null) {
            oldEntry.addThreadId(threadId);
        } else {
            entry.addThreadId(threadId);
            renewExpiration();
        }
    }

private void renewExpiration() {
        ExpirationEntry ee = EXPIRATION_RENEWAL_MAP.get(getEntryName());
        if (ee == null) {
            return;
        }
        Timeout task = commandExecutor.getConnectionManager().newTimeout(new TimerTask() {
            @Override
            public void run(Timeout timeout) throws Exception {
                ExpirationEntry ent = EXPIRATION_RENEWAL_MAP.get(getEntryName());
                if (ent == null) {
                    return;
                }
                Long threadId = ent.getFirstThreadId();
                if (threadId == null) {
                    return;
                }
                RFuture<Boolean> future = renewExpirationAsync(threadId);
                future.onComplete((res, e) -> {
                    if (e != null) {
                        log.error("Can't update lock " + getName() + " expiration", e);
                        return;
                    }
                    if (res) {
                        // reschedule itself
                        renewExpiration();
                    }
                });
            }
        }, internalLockLeaseTime / 3, TimeUnit.MILLISECONDS);
        ee.setTimeout(task);
    }