Question

在Ignite缓存中的事务处理方法中，我们使用多线程方法。

情况1：多个线程在同一键上的高速缓存中插入（无锁定）。

情况2：多个线程使用相似的密钥从缓存中读取数据（在事务锁定中）。

对于情况2，我们遇到以下提到的错误，

java.lang.IllegalStateException：无法启动新事务（当前线程已经有一个事务）：GridNearTxLocal [mappings = IgniteTxMappingsImpl []，nearLocallyMapped = false， colocatedLocallyMapped = false，needCheckBackup = null， hasRemoteLocks = true，trackTimeout = false，lb = null，mvccTracker = null， mvccOp = null，线程=任务290的执行器任务启动工作程序， mappings = IgniteTxMappingsImpl []，super = GridDhtTxLocalAdapter [nearOnOriginatingNode = false，nearNodes = []，dhtNodes = []， explicitLock = false，super = IgniteTxLocalAdapter [completedBase = null， sndTransformedVals = false，depEnabled = false，txState = IgniteTxStateImpl [activeCacheIds = [105038815]，recovery = false，mvccEnabled = false， txMap = [IgniteTxEntry [key = KeyCacheObjectImpl [part = 344，val = abc， hasValBytes = false]，cacheId = 105038815，txKey = IgniteTxKey [key = KeyCacheObjectImpl [part = 344，val = abc，hasValBytes = false]， cacheId = 105038815]，val = [op = READ，val = null]，prevVal = [op = NOOP， val = null]，oldVal = [op = NOOP，val = null]，entryProcessorsCol = null， ttl = -1，conflictExpireTime = -1，conflictVer = null，explicitVer = null， dhtVer = null，filters = null，filtersPassed = false，filtersSet = true， entry = GridDhtDetachedCacheEntry [super = GridDistributedCacheEntry [super = GridCacheMapEntry [key = KeyCacheObjectImpl [part = 344，val = abc， hasValBytes = false]，val = null，ver = GridCacheVersion [topVer = 166176849， order = 1554721151514，nodeOrder = 1]，hash = -1768407104，extras = null，标志= 0]]]，准备= 0，锁定= true， nodeId = 962ec8e9-c7bd-4b73-b4d3-078da58f4439，locMapped = false， expiryPlc = null，transferExpiryPlc = false，标志= 0，partUpdateCntr = 0， serReadVer = null，xidVer = GridCacheVersion [topVer = 166176849， order = 1554721151514，nodeOrder = 44]]]]，mvccWaitTxs = null， qryEnlisted = false，forceSkipCompletedVers = false，super = IgniteTxAdapter [xidVer = GridCacheVersion [topVer = 166176849，order = 1554721151514， nodeOrder = 44]，writeVer = null，隐式= false，loc = true，threadId = 3770， startTime = 1554721555785，nodeId = 6fb5bb88-fc57-478e-9fb9-c26cc8a311e8， startVer = GridCacheVersion [topVer = 166176849，订单= 1554721151514， nodeOrder = 44]，endVer = null，隔离度= REPEATABLE_READ， concurrency = PESSIMISTIC，超时= 0，sysInvalidate = false，sys = false， plc = 2，commitVer = null，finalizing = NONE，invalidParts = null，状态=活动，超时=假，topVer = AffinityTopologyVersion [topVer = 44，minorTopVer = 0]，txCounters = null，持续时间= 156ms， onePhaseCommit = false]，尺寸= 1]]]

代码段如下，

IgniteCache<String, String> cache =  ignite.getOrCreateCache("ABC_CACHE");
Transaction tx = ignite.transactions().txStart(TransactionConcurrency.PESSIMISTIC, TransactionIsolation.REPEATABLE_READ);

String acknowledge = cache.get(key);
if(acknowledge == null || acknowledge.length() == 0) {
if(acknowledge.contains("xyz")) {
    acknowledge.append("mln");
}
    flag = true;
    cache.removeAsync(key);
}else {
    cache.putAsync(key, acknowledge);
}
tx.commit();
tx.close();

还尝试了隔离级别 READ_COMMITTED ，未发生任何错误，但无法实现事务锁定。谁能解释我在哪里弄错了？

Answer 1

也许您确实未能完成某些交易。

我的建议是在try()子句中打开交易，并在close()中finally{}进行交易

java.lang.IllegalStateException：无法启动新事务（当前线程已经有一个事务）

1 个答案: