Exception when accessing from multiple Threads

[PaoloConte]

Hello, I'm not sure if the library is supposed to be thread safe, but I'm having an issue when accessing the database from multiple threads. In particular, the problem seems to be in this section of the library:

      class OfField(override val member: Field) : ValueGetter() {
           override fun get(model: Any): Any? {
               @Suppress("DEPRECATION") val wasAccessible = member.isAccessible
               if (!wasAccessible) member.isAccessible = true
               try {
                   return member.get(model)
               } finally {
                   if (!wasAccessible) member.isAccessible = false
               }
           }
       }

Here the access is not protected by a mutex, so it happens that a Thread tries to get the member while isAccessible has been set to false by another Thread

[PaoloConte]

java.lang.IllegalAccessException: class org.kodein.db.impl.model.jvm.AnnotationMetadataExtractor$ValueGetter$OfField cannot access a member of class xxxxxx.DeviceFaultData with modifiers "private final"
	at java.base/jdk.internal.reflect.Reflection.newIllegalAccessException(Unknown Source)
	at java.base/java.lang.reflect.AccessibleObject.checkAccess(Unknown Source)
	at java.base/java.lang.reflect.Field.checkAccess(Unknown Source)
	at java.base/java.lang.reflect.Field.get(Unknown Source)
	at org.kodein.db.impl.model.jvm.AnnotationMetadataExtractor$ValueGetter$OfField.get(AnnotationMetadataExtractor.kt:34)
	at org.kodein.db.impl.model.jvm.AnnotationMetadataExtractor.extractMetadata(AnnotationMetadataExtractor.kt:110)
	at org.kodein.db.impl.model.ModelDBImpl.getMetadata$kodein_db(ModelDBImpl.kt:72)
	at org.kodein.db.impl.model.ModelWriteModule$DefaultImpls.put(ModelWriteModule.kt:30)
	at org.kodein.db.impl.model.ModelWriteModule$DefaultImpls.put(ModelWriteModule.kt:62)
	at org.kodein.db.impl.model.ModelDBImpl.put(ModelDBImpl.kt:19)
	at org.kodein.db.impl.model.ModelDBImpl.put(ModelDBImpl.kt:84)
	at org.kodein.db.impl.model.cache.CachedModelDB.put(CachedModelDB.kt:24)
	at org.kodein.db.impl.DBImpl.put(DBImpl.kt:16)
	at org.kodein.db.DB$DefaultImpls.put(DB.kt:13)
	at org.kodein.db.impl.DBImpl.put(DBImpl.kt:13)
	at org.kodein.db.DBWrite$DefaultImpls.put(DBWrite.kt:6)
	at org.kodein.db.DB$DefaultImpls.put(DB.kt:11)
	at org.kodein.db.impl.DBImpl.put(DBImpl.kt:13)
	at xxxxx.DeviceRepository.saveDeviceFaultData(DeviceRepository.kt:86)
	at xxxxx.FaultsTask.checkDevice(FaultsTask.kt:47)
	at xxxxx.FaultsTask.run$lambda-0(FaultsTask.kt:29)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.base/java.lang.Thread.run(Unknown Source)

[SalomonBrys]

The library is supposed to be thread-safe. I'll have a look.