isLocked returns wrong value - locking

Question

I'm using Hazelcast for an attempt of distributed locking. The locking seems to work fine but checking if a thread is the owner of a lock or that there even is a lock does not work the way I expect. Please help.
I expect that if I call hazelcastInstance.cpSubsystem.getLock(lockName).isLocked and het true as an answer that I then should be able to unlock it. But the stacktrace shows that it was not locked at all. Even though the check returns true.
I also tried locking on the IMap entry but that had the same result.
fun offer(workItemToOffer: WorkItem, expectedLockState: Boolean = true) {
// Check if the expected state equals to the actual state
val actualLockState = isLocked(workItemToOffer.groupName)
if (expectedLockState != actualLockState) {
log.warn { "offer: '${workItemToOffer.groupName}' should be in the ${if (expectedLockState) "locked" else "unlocked"} state but isn't" }
}
// Release the lock if I have it
if (actualLockState) {
log.info("offer: releasing '${workItemToOffer.groupName}'")
try {
// Release the lock for other instances to work in this same workItem
unlock(workItemToOffer.groupName)
} catch (e: Exception) {
log.error(e) { "offer: error unlocking '${workItemToOffer.groupName}', actualLockState=$actualLockState, expectedLockState=$expectedLockState" }
}
}
}
private fun tryLock(lockName: String) = hazelcastInstance.cpSubsystem.getLock(lockName).tryLock()
private fun unlock(lockName: String) = hazelcastInstance.cpSubsystem.getLock(lockName).unlock()
private fun isLocked(lockName: String) = hazelcastInstance.cpSubsystem.getLock(lockName).isLocked
So the first thing is is that I check if isLocked(). And then if it is locked I do the unlock. But during the unlock I get an exception.
java.lang.IllegalMonitorStateException: Current thread is not owner of the lock!
at com.hazelcast.cp.internal.datastructures.lock.LockService.release(LockService.java:119)
at com.hazelcast.cp.internal.datastructures.lock.operation.UnlockOp.run(UnlockOp.java:45)
at com.hazelcast.cp.internal.operation.unsafe.AbstractUnsafeRaftOp.call(AbstractUnsafeRaftOp.java:67)
at com.hazelcast.spi.impl.operationservice.impl.OperationRunnerImpl.call(OperationRunnerImpl.java:256)
at com.hazelcast.spi.impl.operationservice.impl.OperationRunnerImpl.run(OperationRunnerImpl.java:237)
at com.hazelcast.spi.impl.operationservice.impl.OperationRunnerImpl.run(OperationRunnerImpl.java:452)
at com.hazelcast.spi.impl.operationexecutor.impl.OperationThread.process(OperationThread.java:166)
at com.hazelcast.spi.impl.operationexecutor.impl.OperationThread.process(OperationThread.java:136)
at com.hazelcast.spi.impl.operationexecutor.impl.OperationThread.executeRun(OperationThread.java:123)
at com.hazelcast.internal.util.executor.HazelcastManagedThread.run(HazelcastManagedThread.java:102)
at ------ submitted from ------.()
at com.hazelcast.internal.util.ExceptionUtil.cloneExceptionWithFixedAsyncStackTrace(ExceptionUtil.java:265)
at com.hazelcast.spi.impl.AbstractInvocationFuture.wrapRuntimeException(AbstractInvocationFuture.java:1922)
at com.hazelcast.spi.impl.AbstractInvocationFuture.wrapOrPeel(AbstractInvocationFuture.java:1903)
at com.hazelcast.spi.impl.AbstractInvocationFuture$ExceptionalResult.wrapForJoinInternal(AbstractInvocationFuture.java:1385)
at com.hazelcast.spi.impl.AbstractInvocationFuture.resolveAndThrowForJoinInternal(AbstractInvocationFuture.java:597)
at com.hazelcast.spi.impl.AbstractInvocationFuture.joinInternal(AbstractInvocationFuture.java:581)
at com.hazelcast.cp.internal.datastructures.lock.proxy.AbstractFencedLockProxy.unlock(AbstractFencedLockProxy.java:216)
at com.api.draak.service.WorkItemsService.unlock(WorkItemsService.kt:157)
at com.api.draak.service.WorkItemsService.offer(WorkItemsService.kt:82)
at com.api.draak.service.DraakService.processWorkItem(DraakService.kt:87)
at jdk.internal.reflect.GeneratedMethodAccessor183.invoke(Unknown Source)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.scheduling.support.ScheduledMethodRunnable.run(ScheduledMethodRunnable.java:84)
at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
at java.base/java.util.concurrent.FutureTask.runAndReset(Unknown Source)
at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.base/java.lang.Thread.run(Unknown Source)

Answer 1

Ok, I used the wrong call. I should have used isLockedByCurrentThread. Now I received the status of the lock for the whole cluster. But I needed the lock status for the current instance/thread.