Synchronized user manager

Author: Rothes

bukkit/src/main/kotlin/io/github/rothes/esu/bukkit/user/BukkitUserManager.kt

@@ -14,7 +14,7 @@ object BukkitUserManager: UserManager<CommandSender, PlayerUser>() {
     override fun get(native: CommandSender): PlayerUser {
         val player = native.asPlayer
         val uuid = player.uniqueId
-        return byUuid[uuid]?.also { it.playerCache = player } ?: PlayerUser(player).also { byUuid[uuid] = it }
+        return getCache(uuid)?.also { it.playerCache = player } ?: PlayerUser(player).also { set(uuid, it) }
     }
 
     override fun create(uuid: UUID): PlayerUser = PlayerUser(uuid)

core/src/main/kotlin/io/github/rothes/esu/core/user/UserManager.kt

@@ -2,21 +2,27 @@ package io.github.rothes.esu.core.user
 
 import io.github.rothes.esu.core.util.InitOnce
 import java.util.*
+import java.util.concurrent.locks.ReentrantReadWriteLock
+import kotlin.concurrent.read
+import kotlin.concurrent.write
 
 abstract class UserManager<T, R: User> {
 
-    protected val byUuid = hashMapOf<UUID, R>()
+    private val byUuid = hashMapOf<UUID, R>()
+    private val lock = ReentrantReadWriteLock()
+
+    protected fun set(uuid: UUID, value: R) = lock.write { byUuid.put(uuid, value) }
 
     abstract operator fun get(native: T): R
-    operator fun get(uuid: UUID): R = byUuid[uuid] ?: create(uuid).also { byUuid[uuid] = it }
+    operator fun get(uuid: UUID): R = lock.read { byUuid[uuid] } ?: lock.write { create(uuid).also { byUuid[uuid] = it } }
 
-    fun getCache(uuid: UUID): R? = byUuid[uuid]
-    fun getWithoutCaching(uuid: UUID): R = byUuid[uuid] ?: create(uuid)
+    fun getCache(uuid: UUID): R? = lock.read { byUuid[uuid] }
+    fun getWithoutCaching(uuid: UUID): R = getCache(uuid) ?: create(uuid)
 
     abstract fun create(uuid: UUID): R
 
     abstract fun unload(native: T): R?
-    fun unload(uuid: UUID): R? = byUuid.remove(uuid)
+    fun unload(uuid: UUID): R? = lock.write { byUuid.remove(uuid) }
     fun unload(user: R): R? = unload(user.uuid)
 
 

velocity/src/main/kotlin/io/github/rothes/esu/velocity/user/VelocityUserManager.kt

@@ -14,7 +14,7 @@ object VelocityUserManager: UserManager<CommandSource, PlayerUser>() {
     override fun get(native: CommandSource): PlayerUser {
         val player = native.asPlayer
         val uuid = player.uniqueId
-        return byUuid[uuid]?.also { it.playerCache = player } ?: PlayerUser(player).also { byUuid[uuid] = it }
+        return getCache(uuid)?.also { it.playerCache = player } ?: PlayerUser(player).also { set(uuid, it) }
     }
 
     override fun create(uuid: UUID): PlayerUser = PlayerUser(uuid)