Possible to Encounter ConcurrentModificationException in SessionFactoryImpl #1464
Description
When running load tests with 40 threads using the Neo4j driver version 5.9.0, I encountered a ConcurrentModificationException in the toDistinctSet() method of SessionFactoryImpl.
Proposed Fix: on line 74 in the toDistinctSet method in SessionFactoryImpl, replace HashSet<>() with Collections.synchronizedSet(new HashSet<>())
Original Stack Trace: at java.base/java.util.HashMap$HashIterator.nextNode(HashMap.java:1605) ~[na:na] at java.base/java.util.HashMap$KeyIterator.next(HashMap.java:1628) ~[na:na] at java.base/java.util.Collections$UnmodifiableCollection$1.next(Collections.java:1054) ~[na:na] at org.neo4j.driver.internal.SessionFactoryImpl.toDistinctSet(SessionFactoryImpl.java:76) ~[neo4j-java-driver-5.9.0.jar:5.9.0-1250b2d94997ae49e5a623c52f61636505185057] at org.neo4j.driver.internal.SessionFactoryImpl.newInstance(SessionFactoryImpl.java:64) ~[neo4j-java-driver-5.9.0.jar:5.9.0-1250b2d94997ae49e5a623c52f61636505185057] at org.neo4j.driver.internal.InternalDriver.newSession(InternalDriver.java:218) ~[neo4j-java-driver-5.9.0.jar:5.9.0-1250b2d94997ae49e5a623c52f61636505185057] at org.neo4j.driver.internal.InternalDriver.session(InternalDriver.java:108) ~[neo4j-java-driver-5.9.0.jar:5.9.0-1250b2d94997ae49e5a623c52f61636505185057] at org.neo4j.driver.Driver.session(Driver.java:212) ~[neo4j-java-driver-5.9.0.jar:5.9.0-1250b2d94997ae49e5a623c52f61636505185057] at org.springframework.data.neo4j.core.DefaultReactiveNeo4jClient.lambda$getQueryRunner$0(DefaultReactiveNeo4jClient.java:94) ~[spring-data-neo4j-7.1.2.jar:7.1.2] at reactor.core.publisher.MonoSupplier$MonoSupplierSubscription.request(MonoSupplier.java:126) ~[reactor-core-3.5.8.jar:3.5.8]