DelegateSyncher, a vastly superior version of FieldSynchronizer

2024-02-10 15:37:17 +07:00 · 2024-02-10 15:37:17 +07:00 · 80e5347ac6
commit 80e5347ac6
parent 164ba29add
16 changed files with 1052 additions and 1043 deletions
--- a/gradle.properties
+++ b/gradle.properties
@ -4,7 +4,7 @@ kotlin.code.style=official
 specifyKotlinAsDependency=false

 projectGroup=ru.dbotthepony.kommons
-projectVersion=2.0.0
+projectVersion=2.1.0

 guavaDepVersion=33.0.0
 gsonDepVersion=2.8.9
--- a/linear-algebra/src/main/kotlin/ru/dbotthepony/kommons/io/VectorsIO.kt
+++ b/linear-algebra/src/main/kotlin/ru/dbotthepony/kommons/io/VectorsIO.kt
@ -52,14 +52,26 @@ val Vector4iCodec = StreamCodec.Impl(DataInputStream::readVector4i, DataOutputSt
 val Vector4dCodec = StreamCodec.Impl(DataInputStream::readVector4d, DataOutputStream::writeStruct4d)
 val Vector4fCodec = StreamCodec.Impl(DataInputStream::readVector4f, DataOutputStream::writeStruct4f)

-fun SynchedDelegates.vec2i(value: Vector2i, getter: DelegateGetter<Vector2i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2i> = DelegateSetter.passthrough()): ListenableDelegate<Vector2i> = RegularValue(value, Vector2iCodec, getter, setter)
-fun SynchedDelegates.vec2d(value: Vector2d, getter: DelegateGetter<Vector2d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2d> = DelegateSetter.passthrough()): ListenableDelegate<Vector2d> = RegularValue(value, Vector2dCodec, getter, setter)
-fun SynchedDelegates.vec2f(value: Vector2f, getter: DelegateGetter<Vector2f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2f> = DelegateSetter.passthrough()): ListenableDelegate<Vector2f> = RegularValue(value, Vector2fCodec, getter, setter)
+fun DelegateSyncher.vec2i(value: Vector2i, getter: DelegateGetter<Vector2i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2i> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector2iCodec)
+fun DelegateSyncher.vec2d(value: Vector2d, getter: DelegateGetter<Vector2d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2d> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector2dCodec)
+fun DelegateSyncher.vec2f(value: Vector2f, getter: DelegateGetter<Vector2f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2f> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector2fCodec)

-fun SynchedDelegates.vec3i(value: Vector3i, getter: DelegateGetter<Vector3i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3i> = DelegateSetter.passthrough()): ListenableDelegate<Vector3i> = RegularValue(value, Vector3iCodec, getter, setter)
-fun SynchedDelegates.vec3d(value: Vector3d, getter: DelegateGetter<Vector3d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3d> = DelegateSetter.passthrough()): ListenableDelegate<Vector3d> = RegularValue(value, Vector3dCodec, getter, setter)
-fun SynchedDelegates.vec3f(value: Vector3f, getter: DelegateGetter<Vector3f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3f> = DelegateSetter.passthrough()): ListenableDelegate<Vector3f> = RegularValue(value, Vector3fCodec, getter, setter)
+fun DelegateSyncher.vec3i(value: Vector3i, getter: DelegateGetter<Vector3i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3i> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector3iCodec)
+fun DelegateSyncher.vec3d(value: Vector3d, getter: DelegateGetter<Vector3d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3d> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector3dCodec)
+fun DelegateSyncher.vec3f(value: Vector3f, getter: DelegateGetter<Vector3f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3f> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector3fCodec)

-fun SynchedDelegates.vec4i(value: Vector4i, getter: DelegateGetter<Vector4i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4i> = DelegateSetter.passthrough()): ListenableDelegate<Vector4i> = RegularValue(value, Vector4iCodec, getter, setter)
-fun SynchedDelegates.vec4d(value: Vector4d, getter: DelegateGetter<Vector4d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4d> = DelegateSetter.passthrough()): ListenableDelegate<Vector4d> = RegularValue(value, Vector4dCodec, getter, setter)
-fun SynchedDelegates.vec4f(value: Vector4f, getter: DelegateGetter<Vector4f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4f> = DelegateSetter.passthrough()): ListenableDelegate<Vector4f> = RegularValue(value, Vector4fCodec, getter, setter)
+fun DelegateSyncher.vec4i(value: Vector4i, getter: DelegateGetter<Vector4i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4i> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector4iCodec)
+fun DelegateSyncher.vec4d(value: Vector4d, getter: DelegateGetter<Vector4d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4d> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector4dCodec)
+fun DelegateSyncher.vec4f(value: Vector4f, getter: DelegateGetter<Vector4f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4f> = DelegateSetter.passthrough()) = Slot(ListenableDelegate.maskSmart(value, getter, setter), Vector4fCodec)
+
+fun DelegateSyncher.Group.vec2i(value: Vector2i, getter: DelegateGetter<Vector2i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2i> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector2iCodec)
+fun DelegateSyncher.Group.vec2d(value: Vector2d, getter: DelegateGetter<Vector2d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2d> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector2dCodec)
+fun DelegateSyncher.Group.vec2f(value: Vector2f, getter: DelegateGetter<Vector2f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector2f> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector2fCodec)
+
+fun DelegateSyncher.Group.vec3i(value: Vector3i, getter: DelegateGetter<Vector3i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3i> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector3iCodec)
+fun DelegateSyncher.Group.vec3d(value: Vector3d, getter: DelegateGetter<Vector3d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3d> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector3dCodec)
+fun DelegateSyncher.Group.vec3f(value: Vector3f, getter: DelegateGetter<Vector3f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector3f> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector3fCodec)
+
+fun DelegateSyncher.Group.vec4i(value: Vector4i, getter: DelegateGetter<Vector4i> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4i> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector4iCodec)
+fun DelegateSyncher.Group.vec4d(value: Vector4d, getter: DelegateGetter<Vector4d> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4d> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector4dCodec)
+fun DelegateSyncher.Group.vec4f(value: Vector4f, getter: DelegateGetter<Vector4f> = DelegateGetter.passthrough(), setter: DelegateSetter<Vector4f> = DelegateSetter.passthrough()) = add(ListenableDelegate.maskSmart(value, getter, setter), Vector4fCodec)
--- a/src/main/kotlin/ru/dbotthepony/kommons/collect/ListenableMap.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/collect/ListenableMap.kt
@ -1,33 +1,73 @@
 package ru.dbotthepony.kommons.collect

-abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = HashMap()) : MutableMap<K, V> {
-	protected abstract fun onClear()
-	protected abstract fun onValueAdded(key: K, value: V)
-	protected abstract fun onValueRemoved(key: K, value: V)
+import ru.dbotthepony.kommons.util.Listenable
+import java.util.concurrent.CopyOnWriteArrayList

-	final override val size: Int
+/**
+ * Proxies all operations to [backingMap] along with generating events for [MapListener]s
+ */
+open class ListenableMap<K, V>(protected val backingMap: MutableMap<K, V> = HashMap()) : MutableMap<K, V> {
+	interface MapListener<K, V> {
+		fun onClear()
+		fun onValueAdded(key: K, value: V)
+		fun onValueRemoved(key: K, value: V)
+	}
+
+	protected open fun onClear() {
+		listeners.forEach { it.callback.onClear() }
+	}
+
+	protected open fun onValueAdded(key: K, value: V) {
+		listeners.forEach { it.callback.onValueAdded(key, value) }
+	}
+
+	protected open fun onValueRemoved(key: K, value: V) {
+		listeners.forEach { it.callback.onValueRemoved(key, value) }
+	}
+
+	protected inner class Listener(val callback: MapListener<K, V>) : Listenable.L {
+		init {
+			listeners.add(this)
+		}
+
+		override fun remove() {
+			listeners.remove(this)
+		}
+	}
+
+	protected val listeners = CopyOnWriteArrayList<Listener>()
+
+	fun addListener(listener: MapListener<K, V>): Listenable.L {
+		return Listener(listener)
+	}
+
+	fun clearListeners() {
+		listeners.clear()
+	}
+
+	override val size: Int
 		get() = backingMap.size

-	final override fun containsKey(key: K): Boolean {
+	override fun containsKey(key: K): Boolean {
 		return backingMap.containsKey(key)
 	}

-	final override fun containsValue(value: V): Boolean {
+	override fun containsValue(value: V): Boolean {
 		return backingMap.containsValue(value)
 	}

-	final override fun get(key: K): V? {
+	override fun get(key: K): V? {
 		return backingMap[key]
 	}

-	final override fun isEmpty(): Boolean {
+	override fun isEmpty(): Boolean {
 		return backingMap.isEmpty()
 	}

-	final override val entries: MutableSet<MutableMap.MutableEntry<K, V>> by lazy {
+	override val entries: MutableSet<MutableMap.MutableEntry<K, V>> by lazy {
 		object : MutableSet<MutableMap.MutableEntry<K, V>> {
 			override fun add(element: MutableMap.MutableEntry<K, V>): Boolean {
-				this@ProxiedMap[element.key] = element.value
+				this@ListenableMap[element.key] = element.value
 				return true
 			}

@ -40,10 +80,10 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 			}

 			override fun clear() {
-				this@ProxiedMap.clear()
+				this@ListenableMap.clear()
 			}

-			private val setParent = this@ProxiedMap.backingMap.entries
+			private val setParent = this@ListenableMap.backingMap.entries

 			override fun iterator(): MutableIterator<MutableMap.MutableEntry<K, V>> {
 				return object : MutableIterator<MutableMap.MutableEntry<K, V>> {
@ -116,9 +156,9 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 		}
 	}

-	final override val keys: MutableSet<K> by lazy {
+	override val keys: MutableSet<K> by lazy {
 		object : MutableSet<K> {
-			val parent = this@ProxiedMap.backingMap.keys
+			val parent = this@ListenableMap.backingMap.keys

 			override fun add(element: K): Boolean {
 				throw UnsupportedOperationException()
@ -129,7 +169,7 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 			}

 			override fun clear() {
-				this@ProxiedMap.clear()
+				this@ListenableMap.clear()
 			}

 			override fun iterator(): MutableIterator<K> {
@ -147,7 +187,7 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has

 					override fun remove() {
 						val last = last ?: throw IllegalStateException("Never called next()")
-						val value = this@ProxiedMap[last] ?: throw ConcurrentModificationException()
+						val value = this@ListenableMap[last] ?: throw ConcurrentModificationException()
 						parentIterator.remove()
 						onValueRemoved(last, value)
 					}
@ -155,7 +195,7 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 			}

 			override fun remove(element: K): Boolean {
-				return this@ProxiedMap.remove(element) != null
+				return this@ListenableMap.remove(element) != null
 			}

 			override fun removeAll(elements: Collection<K>): Boolean {
@ -199,9 +239,9 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 		}
 	}

-	final override val values: MutableCollection<V> by lazy {
+	override val values: MutableCollection<V> by lazy {
 		object : MutableCollection<V> {
-			private val parent = this@ProxiedMap.backingMap.values
+			private val parent = this@ListenableMap.backingMap.values

 			override val size: Int
 				get() = parent.size
@ -227,7 +267,7 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 			}

 			override fun clear() {
-				this@ProxiedMap.clear()
+				this@ListenableMap.clear()
 			}

 			override fun iterator(): MutableIterator<V> {
@ -249,8 +289,8 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 			}

 			override fun remove(element: V): Boolean {
-				val indexOf = this@ProxiedMap.backingMap.firstNotNullOfOrNull { if (it.value == element) it.key else null } ?: return false
-				this@ProxiedMap.remove(indexOf)
+				val indexOf = this@ListenableMap.backingMap.firstNotNullOfOrNull { if (it.value == element) it.key else null } ?: return false
+				this@ListenableMap.remove(indexOf)
 				return true
 			}

@ -296,7 +336,7 @@ abstract class ProxiedMap<K, V>(protected val backingMap: MutableMap<K, V> = Has
 		return existing
 	}

-	final override fun putAll(from: Map<out K, V>) {
+	override fun putAll(from: Map<out K, V>) {
 		for ((k, v) in from) {
 			this[k] = v
 		}
--- a/src/main/kotlin/ru/dbotthepony/kommons/collect/ListenableSet.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/collect/ListenableSet.kt
@ -0,0 +1,141 @@
+package ru.dbotthepony.kommons.collect
+
+import ru.dbotthepony.kommons.util.Listenable
+import java.util.concurrent.CopyOnWriteArrayList
+
+/**
+ * Proxies all operations to [backingSet] along with generating events for [SetListener]s
+ */
+open class ListenableSet<E>(protected val backingSet: MutableSet<E>) : MutableSet<E> {
+	interface SetListener<E> {
+		fun onClear()
+		fun onValueAdded(element: E)
+		fun onValueRemoved(element: E)
+	}
+
+	protected open fun onClear() {
+		listeners.forEach { it.callback.onClear() }
+	}
+
+	protected open fun onValueAdded(element: E) {
+		listeners.forEach { it.callback.onValueAdded(element) }
+	}
+
+	protected open fun onValueRemoved(element: E) {
+		listeners.forEach { it.callback.onValueRemoved(element) }
+	}
+
+	protected inner class Listener(val callback: SetListener<E>) : Listenable.L {
+		init {
+			listeners.add(this)
+		}
+
+		override fun remove() {
+			listeners.remove(this)
+		}
+	}
+
+	protected val listeners = CopyOnWriteArrayList<Listener>()
+
+	fun addListener(listener: SetListener<E>): Listenable.L {
+		return Listener(listener)
+	}
+
+	fun clearListeners() {
+		listeners.clear()
+	}
+
+	override fun add(element: E): Boolean {
+		if (backingSet.add(element)) {
+			onValueAdded(element)
+			return true
+		}
+
+		return false
+	}
+
+	override fun remove(element: E): Boolean {
+		if (backingSet.remove(element)) {
+			onValueRemoved(element)
+			return true
+		}
+
+		return false
+	}
+
+	override fun addAll(elements: Collection<E>): Boolean {
+		var any = false
+		elements.forEach { any = add(it) || any }
+		return any
+	}
+
+	override fun clear() {
+		if (backingSet.isNotEmpty()) {
+			backingSet.clear()
+			onClear()
+		}
+	}
+
+	override fun removeAll(elements: Collection<E>): Boolean {
+		var any = false
+		elements.forEach { any = remove(it) || any }
+		return any
+	}
+
+	override fun retainAll(elements: Collection<E>): Boolean {
+		var any = false
+
+		val iterator = iterator()
+
+		for (value in iterator) {
+			if (value !in elements) {
+				any = true
+				iterator.remove()
+			}
+		}
+
+		return any
+	}
+
+	override fun contains(element: E): Boolean {
+		return element in backingSet
+	}
+
+	override fun containsAll(elements: Collection<E>): Boolean {
+		return elements.all { it in backingSet }
+	}
+
+	override fun isEmpty(): Boolean {
+		return backingSet.isEmpty()
+	}
+
+	override val size: Int
+		get() = backingSet.size
+
+	override fun iterator(): MutableIterator<E> {
+		return object : MutableIterator<E> {
+			private val parent = backingSet.iterator()
+			private var lastElement: Any? = Mark
+
+			override fun hasNext(): Boolean {
+				return parent.hasNext()
+			}
+
+			override fun next(): E {
+				return parent.next().also { lastElement = it }
+			}
+
+			override fun remove() {
+				parent.remove()
+				val lastElement = lastElement
+
+				if (lastElement !== Mark) {
+					this.lastElement = Mark
+					onValueRemoved(lastElement as E)
+				}
+			}
+		}
+	}
+
+	private object Mark
+}
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/ChangesetAction.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/ChangesetAction.kt
@ -1,5 +0,0 @@
-package ru.dbotthepony.kommons.io
-
-enum class ChangesetAction {
-	CLEAR, ADD, REMOVE
-}
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/DecimalIO.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/DecimalIO.kt
@ -1,23 +0,0 @@
-package ru.dbotthepony.kommons.io
-
-import ru.dbotthepony.kommons.math.Decimal
-import java.io.DataInputStream
-import java.io.DataOutputStream
-import java.io.InputStream
-import java.io.OutputStream
-
-fun InputStream.readDecimal(): Decimal {
-	val size = readVarInt()
-	require(size >= 0) { "Negative payload size: $size" }
-	val bytes = ByteArray(size)
-	read(bytes)
-	return Decimal.fromByteArray(bytes)
-}
-
-fun OutputStream.writeDecimal(value: Decimal) {
-	val bytes = value.toByteArray()
-	writeVarInt(bytes.size)
-	write(bytes)
-}
-
-val DecimalValueCodec = StreamCodec.Impl(DataInputStream::readDecimal, DataOutputStream::writeDecimal)
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/DelegateSyncher.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/DelegateSyncher.kt
@ -0,0 +1,768 @@
+package ru.dbotthepony.kommons.io
+
+import it.unimi.dsi.fastutil.ints.IntAVLTreeSet
+import it.unimi.dsi.fastutil.io.FastByteArrayOutputStream
+import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap
+import it.unimi.dsi.fastutil.objects.ObjectAVLTreeSet
+import it.unimi.dsi.fastutil.objects.ObjectOpenHashSet
+import ru.dbotthepony.kommons.collect.ListenableMap
+import ru.dbotthepony.kommons.collect.ListenableSet
+import ru.dbotthepony.kommons.math.Decimal
+import ru.dbotthepony.kommons.util.Delegate
+import ru.dbotthepony.kommons.util.DelegateGetter
+import ru.dbotthepony.kommons.util.DelegateSetter
+import ru.dbotthepony.kommons.util.Listenable
+import ru.dbotthepony.kommons.util.ListenableDelegate
+import ru.dbotthepony.kommons.util.Observer
+import java.io.DataInputStream
+import java.io.DataOutputStream
+import java.io.InputStream
+import java.util.*
+import java.util.concurrent.ConcurrentLinkedQueue
+import java.util.concurrent.CopyOnWriteArrayList
+import java.util.concurrent.atomic.AtomicBoolean
+import java.util.concurrent.locks.ReentrantLock
+import java.util.function.Consumer
+import java.util.function.Supplier
+import kotlin.ConcurrentModificationException
+import kotlin.collections.ArrayList
+import kotlin.concurrent.withLock
+
+/**
+ * Synches attached delegates by serializing delta state on one end and deserializing on another.
+ *
+ * Precautions when using this class:
+ * 1. Entire class is **not** thread safe, with the exception of attached delegates triggering [Listenable.addListener] listeners
+ * (this includes calling [observe] from multiple threads, but why would you do this).
+ * 2. [addListener] listeners are expected to be called once when [isDirty] turns true **on best effort**.
+ * If syncher is running in highly congested environment (multiple threads are mutating attached delegates)
+ * listeners may be called more than once IF [constructPayload] call is ongoing.
+ * 3. [addListener] listeners on both [DelegateSyncher] and [DelegateSyncher.Slot]s are called on the same thread
+ * where delegate mutation/observation/etc occurred. If you need to mutate [DelegateSyncher] internal structure (add/remove
+ * slots) you **MUST** synchronize mutations by yourself if listener in question is expected to be called from multiple threads.
+ * 4. When using [DelegateSyncher] in single-threaded context, all operations are legal at any point in time, including [DelegateSyncher.Slot]
+ * addition/removal during [observe], [readPayload] or [addListener] callback on either [DelegateSyncher] or [DelegateSyncher.Slot].
+ * 5. Calling [DelegateSyncher.AbstractSlot.remove] does not shift any subsequent slots down, leaving all slot IDs intact.
+ * Gaps are filled when new slots are created.
+ */
+class DelegateSyncher : Listenable<Unit>, Observer {
+	private val slots = ArrayList<AbstractSlot?>()
+	private val observers = CopyOnWriteArrayList<AbstractSlot>()
+	private val dirtySlots = ConcurrentLinkedQueue<AbstractSlot>()
+	private val dirtySubs = Listenable.Void()
+	private val gaps = IntAVLTreeSet()
+
+	@Volatile
+	private var changeset = 0
+
+	var isRemote = false
+		private set
+
+	private val isDirtyF = AtomicBoolean()
+	val isDirty: Boolean
+		get() = isDirtyF.get()
+
+	override fun observe(): Boolean {
+		var any = false
+		observers.forEach { any = it.observe() || any }
+		return any
+	}
+
+	override fun addListener(listener: Runnable): Listenable.L {
+		return dirtySubs.addListener(listener)
+	}
+
+	override fun addListener(listener: Consumer<Unit>): Listenable.L {
+		return dirtySubs.addListener(listener)
+	}
+
+	fun constructPayload(): FastByteArrayOutputStream? {
+		if (!isDirtyF.get()) return null
+
+		val slots = ObjectAVLTreeSet<AbstractSlot>()
+
+		do {
+			var poll = dirtySlots.poll()
+
+			while (poll != null) {
+				slots.add(poll)
+				poll = dirtySlots.poll()
+			}
+		} while (isDirtyF.compareAndSet(true, false))
+
+		val stream = FastByteArrayOutputStream()
+		val dataStream = DataOutputStream(stream)
+
+		for (slot in slots) {
+			dataStream.writeVarInt(slot.id + 1)
+			slot.write(dataStream)
+		}
+
+		dataStream.writeVarInt(0)
+		return stream
+	}
+
+	fun readPayload(stream: DataInputStream) {
+		var nextId = stream.readVarInt()
+
+		while (nextId > 0) {
+			val slot = slots
+			nextId = stream.readVarInt()
+		}
+	}
+
+	fun readPayload(stream: InputStream) {
+		readPayload(DataInputStream(stream))
+	}
+
+	abstract inner class AbstractSlot : Observer, Comparable<AbstractSlot> {
+		protected val isDirtySlotF = AtomicBoolean(true)
+
+		val isDirty: Boolean
+			get() = isDirtySlotF.get()
+
+		var isRemoved = false
+			private set
+
+		val id: Int
+
+		init {
+			val changeset = ++this@DelegateSyncher.changeset
+
+			if (gaps.isNotEmpty()) {
+				val gap = gaps.firstInt()
+				gaps.remove(gap)
+				id = gap
+				check(slots[id] == null) { "Expected slot $id to be empty" }
+				slots[id] = this
+			} else {
+				id = slots.size
+				slots.add(this)
+			}
+
+			dirtySlots.add(this)
+
+			if (changeset != ++this@DelegateSyncher.changeset) {
+				throw ConcurrentModificationException("Manipulating DelegateSyncher across multiple threads")
+			}
+
+			if (isDirtyF.compareAndSet(false, true)) {
+				dirtySubs.run()
+			}
+		}
+
+		final override fun compareTo(other: AbstractSlot): Int {
+			return id.compareTo(other.id)
+		}
+
+		protected abstract fun actuallyRemove()
+
+		protected fun markDirty() {
+			check(!isRemoved) { "This network slot was removed" }
+
+			if (!isRemote && isDirtySlotF.compareAndSet(false, true)) {
+				dirtySlots.add(this)
+
+				if (!isDirtyF.get() && !dirtySlots.isEmpty() && isDirtyF.compareAndSet(false, true) && !dirtySlots.isEmpty()) {
+					dirtySubs.run()
+				}
+			}
+		}
+
+		fun remove() {
+			if (!isRemoved) {
+				val changeset = ++this@DelegateSyncher.changeset
+
+				isRemoved = true
+				slots[id] = null
+				observers.remove(this)
+
+				if (id == slots.size - 1) {
+					slots.removeAt(id)
+				} else {
+					gaps.add(id)
+				}
+
+				if (isDirtySlotF.get()) {
+					dirtySlots.remove(this)
+					this@DelegateSyncher.isDirtyF.set(dirtySlots.isNotEmpty())
+				}
+
+				actuallyRemove()
+
+				if (changeset != ++this@DelegateSyncher.changeset) {
+					throw ConcurrentModificationException("Manipulating DelegateSyncher across multiple threads")
+				}
+			}
+		}
+
+		abstract fun write(stream: DataOutputStream)
+		abstract fun read(stream: DataInputStream)
+	}
+
+	inner class Slot<V>(private val parent: ListenableDelegate<V>, private val codec: StreamCodec<V>) : AbstractSlot(), ListenableDelegate<V> {
+		private val subs = Listenable.Impl<V>()
+
+		private val parentSub = parent.addListener(Consumer {
+			markDirty()
+			subs.accept(it)
+		})
+
+		override fun get(): V {
+			check(!isRemoved) { "This network slot was removed" }
+			return parent.get()
+		}
+
+		override fun accept(t: V) {
+			check(!isRemoved) { "This network slot was removed" }
+			parent.accept(t)
+		}
+
+		override fun addListener(listener: Consumer<V>): Listenable.L {
+			check(!isRemoved) { "This network slot was removed" }
+			return subs.addListener(listener)
+		}
+
+		override fun write(stream: DataOutputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			codec.write(stream, parent.get())
+			isDirtySlotF.set(false)
+		}
+
+		override fun read(stream: DataInputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			parent.accept(codec.read(stream))
+		}
+
+		override fun observe(): Boolean {
+			check(!isRemoved) { "This network slot was removed" }
+			return false
+		}
+
+		override fun actuallyRemove() {
+			subs.clear()
+			parentSub.remove()
+		}
+	}
+
+	inner class ObservedSlot<V>(private val parent: Delegate<V>, private val codec: StreamCodec<V>) : AbstractSlot(), ListenableDelegate<V> {
+		private var lastValue: Any? = Mark
+		private val localLock = ReentrantLock() // avoid deadlock when code inside subscribers cause another value observation
+		private val subs = Listenable.Impl<V>()
+
+		override fun actuallyRemove() {
+			subs.clear()
+			lastValue = Mark
+		}
+
+		override fun write(stream: DataOutputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			codec.write(stream, parent.get())
+		}
+
+		override fun read(stream: DataInputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			val read = codec.read(stream)
+			parent.accept(read)
+
+			localLock.withLock {
+				lastValue = read
+				subs.accept(read)
+			}
+		}
+
+		override fun observe(): Boolean {
+			check(!isRemoved) { "This network slot was removed" }
+			if (isRemote) return false
+
+			val get = get()
+
+			if (lastValue === Mark || !codec.compare(get, lastValue as V)) {
+				localLock.withLock {
+					if (lastValue === Mark || !codec.compare(get, lastValue as V)) {
+						markDirty()
+						lastValue = codec.copy(get)
+						subs.accept(get)
+						return true
+					}
+				}
+			}
+
+			return false
+		}
+
+		override fun get(): V {
+			check(!isRemoved) { "This network slot was removed" }
+			val get = get()
+
+			if (!isRemote) {
+				if (lastValue === Mark || !codec.compare(get, lastValue as V)) {
+					localLock.withLock {
+						if (lastValue === Mark || !codec.compare(get, lastValue as V)) {
+							markDirty()
+							lastValue = codec.copy(get)
+							subs.accept(get)
+						}
+					}
+				}
+			}
+
+			return get
+		}
+
+		override fun accept(t: V) {
+			check(!isRemoved) { "This network slot was removed" }
+
+			parent.accept(t)
+
+			localLock.withLock {
+				lastValue = codec.copy(t)
+				subs.accept(t)
+			}
+		}
+
+		override fun addListener(listener: Consumer<V>): Listenable.L {
+			check(!isRemoved) { "This network slot was removed" }
+			return subs.addListener(listener)
+		}
+	}
+
+	inner class ComputedSlot<V>(parent: Supplier<V>, private val codec: StreamCodec<V>) : AbstractSlot(), ListenableDelegate<V> {
+		private val shadow = ListenableDelegate.CustomShadow(parent, codec::compare, codec::copy)
+
+		override fun write(stream: DataOutputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			codec.write(stream, shadow.get())
+			isDirtySlotF.set(false)
+		}
+
+		override fun read(stream: DataInputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			shadow.accept(codec.read(stream))
+		}
+
+		override fun observe(): Boolean {
+			check(!isRemoved) { "This network slot was removed" }
+			if (shadow.observe()) {
+				markDirty()
+				return true
+			}
+
+			return false
+		}
+
+		override fun get(): V {
+			check(!isRemoved) { "This network slot was removed" }
+			return shadow.get()
+		}
+
+		override fun accept(t: V) {
+			check(!isRemoved) { "This network slot was removed" }
+			shadow.accept(t)
+		}
+
+		override fun addListener(listener: Consumer<V>): Listenable.L {
+			check(!isRemoved) { "This network slot was removed" }
+			return shadow.addListener(listener)
+		}
+
+		override fun actuallyRemove() {
+			shadow.clearListeners()
+		}
+	}
+
+	inner class SetSlot<E>(val value: ListenableSet<E>, private val codec: StreamCodec<E>) : AbstractSlot(), ListenableSet.SetListener<E>, Listenable<ListenableSet<E>> {
+		private val sub = value.addListener(this)
+		private val subs = Listenable.Impl<ListenableSet<E>>()
+		private val backlog = ArrayList<DataOutputStream.() -> Unit>()
+
+		override fun onClear() {
+			check(!isRemoved) { "This network slot was removed" }
+			synchronized(backlog) {
+				markDirty()
+
+				backlog.clear()
+				backlog.add { write(CLEAR) }
+			}
+		}
+
+		override fun onValueAdded(element: E) {
+			check(!isRemoved) { "This network slot was removed" }
+			val copy = codec.copy(element)
+
+			synchronized(backlog) {
+				markDirty()
+
+				backlog.add {
+					write(ADD)
+					codec.write(this, copy)
+				}
+			}
+		}
+
+		override fun onValueRemoved(element: E) {
+			check(!isRemoved) { "This network slot was removed" }
+			val copy = codec.copy(element)
+
+			synchronized(backlog) {
+				markDirty()
+
+				backlog.add {
+					write(REMOVE)
+					codec.write(this, copy)
+				}
+			}
+		}
+
+		override fun actuallyRemove() {
+			backlog.clear()
+			sub.remove()
+			subs.clear()
+		}
+
+		override fun write(stream: DataOutputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			synchronized(backlog) {
+				isDirtySlotF.set(false)
+				backlog.forEach { it(stream) }
+				backlog.clear()
+			}
+
+			stream.write(END)
+		}
+
+		override fun read(stream: DataInputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			var action = stream.read()
+
+			while (true) {
+				when (action) {
+					ADD -> value.add(codec.read(stream))
+					REMOVE -> value.remove(codec.read(stream))
+					CLEAR -> value.clear()
+					else -> break
+				}
+
+				action = stream.read()
+			}
+
+			subs.accept(value)
+		}
+
+		override fun observe(): Boolean {
+			check(!isRemoved) { "This network slot was removed" }
+			return false
+		}
+
+		override fun addListener(listener: Consumer<ListenableSet<E>>): Listenable.L {
+			check(!isRemoved) { "This network slot was removed" }
+			return subs.addListener(listener)
+		}
+	}
+
+	inner class MapSlot<K, V>(val value: ListenableMap<K, V>, private val keyCodec: StreamCodec<K>, private val valueCodec: StreamCodec<V>) : AbstractSlot(), Listenable<ListenableMap<K, V>>, ListenableMap.MapListener<K, V> {
+		private val sub = value.addListener(this)
+		private val subs = Listenable.Impl<ListenableMap<K, V>>()
+		private val backlog = ArrayList<DataOutputStream.() -> Unit>()
+
+		override fun onClear() {
+			check(!isRemoved) { "This network slot was removed" }
+			synchronized(backlog) {
+				markDirty()
+
+				backlog.clear()
+				backlog.add { write(CLEAR) }
+			}
+		}
+
+		override fun onValueAdded(key: K, value: V) {
+			check(!isRemoved) { "This network slot was removed" }
+			val keyCopy = keyCodec.copy(key)
+			val valueCopy = valueCodec.copy(value)
+
+			synchronized(backlog) {
+				markDirty()
+
+				backlog.add {
+					write(ADD)
+					keyCodec.write(this, keyCopy)
+					valueCodec.write(this, valueCopy)
+				}
+			}
+		}
+
+		override fun onValueRemoved(key: K, value: V) {
+			check(!isRemoved) { "This network slot was removed" }
+			val keyCopy = keyCodec.copy(key)
+
+			synchronized(backlog) {
+				markDirty()
+
+				backlog.add {
+					write(REMOVE)
+					keyCodec.write(this, keyCopy)
+				}
+			}
+		}
+
+		override fun actuallyRemove() {
+			backlog.clear()
+			sub.remove()
+			subs.clear()
+		}
+
+		override fun write(stream: DataOutputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			synchronized(backlog) {
+				isDirtySlotF.set(false)
+				backlog.forEach { it(stream) }
+				backlog.clear()
+			}
+
+			stream.write(END)
+		}
+
+		override fun read(stream: DataInputStream) {
+			check(!isRemoved) { "This network slot was removed" }
+			var action = stream.read()
+
+			while (true) {
+				when (action) {
+					ADD -> value.put(keyCodec.read(stream), valueCodec.read(stream))
+					REMOVE -> value.remove(keyCodec.read(stream))
+					CLEAR -> value.clear()
+					else -> break
+				}
+
+				action = stream.read()
+			}
+
+			subs.accept(value)
+		}
+
+		override fun addListener(listener: Consumer<ListenableMap<K, V>>): Listenable.L {
+			check(!isRemoved) { "This network slot was removed" }
+			return subs.addListener(listener)
+		}
+
+		override fun observe(): Boolean {
+			check(!isRemoved) { "This network slot was removed" }
+			return false
+		}
+	}
+
+	fun <V> add(delegate: ListenableDelegate<V>, codec: StreamCodec<V>): Slot<V> {
+		return Slot(delegate, codec)
+	}
+
+	fun <V> add(delegate: Delegate<V>, codec: StreamCodec<V>): ObservedSlot<V> {
+		return ObservedSlot(delegate, codec)
+	}
+
+	fun <V> add(delegate: Supplier<V>, codec: StreamCodec<V>): ComputedSlot<V> {
+		return ComputedSlot(delegate, codec)
+	}
+
+	fun <E> add(delegate: ListenableSet<E>, codec: StreamCodec<E>): SetSlot<E> {
+		return SetSlot(delegate, codec)
+	}
+
+	fun <K, V> add(delegate: ListenableMap<K, V>, keyCodec: StreamCodec<K>, valueCodec: StreamCodec<V>): MapSlot<K, V> {
+		return MapSlot(delegate, keyCodec, valueCodec)
+	}
+
+	@JvmName("vbyte")
+	@JvmOverloads
+	fun byte(value: Byte = 0, getter: DelegateGetter<Byte> = DelegateGetter.passthrough(), setter: DelegateSetter<Byte> = DelegateSetter.passthrough()): Slot<Byte> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), ByteValueCodec)
+	}
+
+	@JvmName("vshort")
+	@JvmOverloads
+	fun short(value: Short = 0, getter: DelegateGetter<Short> = DelegateGetter.passthrough(), setter: DelegateSetter<Short> = DelegateSetter.passthrough()): Slot<Short> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), ShortValueCodec)
+	}
+
+	@JvmName("vchar")
+	@JvmOverloads
+	fun char(value: Char, getter: DelegateGetter<Char> = DelegateGetter.passthrough(), setter: DelegateSetter<Char> = DelegateSetter.passthrough()): Slot<Char> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), CharValueCodec)
+	}
+
+	@JvmName("vint")
+	@JvmOverloads
+	fun int(value: Int = 0, getter: DelegateGetter<Int> = DelegateGetter.passthrough(), setter: DelegateSetter<Int> = DelegateSetter.passthrough()): Slot<Int> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), VarIntValueCodec)
+	}
+
+	@JvmName("vlong")
+	@JvmOverloads
+	fun long(value: Long = 0L, getter: DelegateGetter<Long> = DelegateGetter.passthrough(), setter: DelegateSetter<Long> = DelegateSetter.passthrough()): Slot<Long> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), VarLongValueCodec)
+	}
+
+	@JvmName("vfloat")
+	@JvmOverloads
+	fun float(value: Float = 0f, getter: DelegateGetter<Float> = DelegateGetter.passthrough(), setter: DelegateSetter<Float> = DelegateSetter.passthrough()): Slot<Float> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), FloatValueCodec)
+	}
+
+	@JvmName("vdouble")
+	@JvmOverloads
+	fun double(value: Double = 0.0, getter: DelegateGetter<Double> = DelegateGetter.passthrough(), setter: DelegateSetter<Double> = DelegateSetter.passthrough()): Slot<Double> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), DoubleValueCodec)
+	}
+
+	@JvmName("vboolean")
+	@JvmOverloads
+	fun boolean(value: Boolean = false, getter: DelegateGetter<Boolean> = DelegateGetter.passthrough(), setter: DelegateSetter<Boolean> = DelegateSetter.passthrough()): Slot<Boolean> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), BooleanValueCodec)
+	}
+
+	@JvmOverloads
+	fun string(value: String, getter: DelegateGetter<String> = DelegateGetter.passthrough(), setter: DelegateSetter<String> = DelegateSetter.passthrough()): Slot<String> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), BinaryStringCodec)
+	}
+
+	@JvmOverloads
+	fun uuid(value: UUID, getter: DelegateGetter<UUID> = DelegateGetter.passthrough(), setter: DelegateSetter<UUID> = DelegateSetter.passthrough()): Slot<UUID> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), UUIDValueCodec)
+	}
+
+	@JvmOverloads
+	fun decimal(value: Decimal = Decimal.ZERO, getter: DelegateGetter<Decimal> = DelegateGetter.passthrough(), setter: DelegateSetter<Decimal> = DelegateSetter.passthrough()): Slot<Decimal> {
+		return add(ListenableDelegate.maskSmart(value, getter, setter), DecimalValueCodec)
+	}
+
+	private object Mark
+
+	/**
+	 * Helper class which allows quick creation of [DelegateSyncher] from attached delegates.
+	 */
+	class Group {
+		private val constructors = ArrayList<DelegateSyncher.() -> Unit>()
+
+		fun <D : ListenableDelegate<V>, V> add(delegate: D, codec: StreamCodec<V>): D {
+			constructors.add {
+				add(delegate, codec)
+			}
+
+			return delegate
+		}
+
+		fun <D : Delegate<V>, V> add(delegate: D, codec: StreamCodec<V>): D {
+			constructors.add {
+				add(delegate, codec)
+			}
+
+			return delegate
+		}
+
+		fun <D : ListenableSet<E>, E> add(delegate: D, codec: StreamCodec<E>): D {
+			constructors.add {
+				add(delegate, codec)
+			}
+
+			return delegate
+		}
+
+		fun <D : ListenableMap<K, V>, K, V> add(delegate: D, keyCodec: StreamCodec<K>, valueCodec: StreamCodec<V>): D {
+			constructors.add {
+				add(delegate, keyCodec, valueCodec)
+			}
+
+			return delegate
+		}
+
+		@JvmName("vbyte")
+		@JvmOverloads
+		fun byte(value: Byte = 0, getter: DelegateGetter<Byte> = DelegateGetter.passthrough(), setter: DelegateSetter<Byte> = DelegateSetter.passthrough()): ListenableDelegate<Byte> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), ByteValueCodec)
+		}
+
+		@JvmName("vshort")
+		@JvmOverloads
+		fun short(value: Short = 0, getter: DelegateGetter<Short> = DelegateGetter.passthrough(), setter: DelegateSetter<Short> = DelegateSetter.passthrough()): ListenableDelegate<Short> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), ShortValueCodec)
+		}
+
+		@JvmName("vchar")
+		@JvmOverloads
+		fun char(value: Char, getter: DelegateGetter<Char> = DelegateGetter.passthrough(), setter: DelegateSetter<Char> = DelegateSetter.passthrough()): ListenableDelegate<Char> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), CharValueCodec)
+		}
+
+		@JvmName("vint")
+		@JvmOverloads
+		fun int(value: Int = 0, getter: DelegateGetter<Int> = DelegateGetter.passthrough(), setter: DelegateSetter<Int> = DelegateSetter.passthrough()): ListenableDelegate<Int> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), VarIntValueCodec)
+		}
+
+		@JvmName("vlong")
+		@JvmOverloads
+		fun long(value: Long = 0L, getter: DelegateGetter<Long> = DelegateGetter.passthrough(), setter: DelegateSetter<Long> = DelegateSetter.passthrough()): ListenableDelegate<Long> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), VarLongValueCodec)
+		}
+
+		@JvmName("vfloat")
+		@JvmOverloads
+		fun float(value: Float = 0f, getter: DelegateGetter<Float> = DelegateGetter.passthrough(), setter: DelegateSetter<Float> = DelegateSetter.passthrough()): ListenableDelegate<Float> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), FloatValueCodec)
+		}
+
+		@JvmName("vdouble")
+		@JvmOverloads
+		fun double(value: Double = 0.0, getter: DelegateGetter<Double> = DelegateGetter.passthrough(), setter: DelegateSetter<Double> = DelegateSetter.passthrough()): ListenableDelegate<Double> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), DoubleValueCodec)
+		}
+
+		@JvmName("vboolean")
+		@JvmOverloads
+		fun boolean(value: Boolean = false, getter: DelegateGetter<Boolean> = DelegateGetter.passthrough(), setter: DelegateSetter<Boolean> = DelegateSetter.passthrough()): ListenableDelegate<Boolean> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), BooleanValueCodec)
+		}
+
+		@JvmOverloads
+		fun string(value: String, getter: DelegateGetter<String> = DelegateGetter.passthrough(), setter: DelegateSetter<String> = DelegateSetter.passthrough()): ListenableDelegate<String> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), BinaryStringCodec)
+		}
+
+		@JvmOverloads
+		fun uuid(value: UUID, getter: DelegateGetter<UUID> = DelegateGetter.passthrough(), setter: DelegateSetter<UUID> = DelegateSetter.passthrough()): ListenableDelegate<UUID> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), UUIDValueCodec)
+		}
+
+		@JvmOverloads
+		fun decimal(value: Decimal = Decimal.ZERO, getter: DelegateGetter<Decimal> = DelegateGetter.passthrough(), setter: DelegateSetter<Decimal> = DelegateSetter.passthrough()): ListenableDelegate<Decimal> {
+			return add(ListenableDelegate.maskSmart(value, getter, setter), DecimalValueCodec)
+		}
+
+		fun <E> set(codec: StreamCodec<E>, backing: MutableSet<E> = ObjectOpenHashSet()): ListenableSet<E> {
+			val delegate = ListenableSet(backing)
+			constructors.add { add(delegate, codec) }
+			return delegate
+		}
+
+		fun <K, V> map(keyCodec: StreamCodec<K>, valueCodec: StreamCodec<V>, backing: MutableMap<K, V> = Object2ObjectOpenHashMap()): ListenableMap<K, V> {
+			val delegate = ListenableMap(backing)
+			constructors.add { add(delegate, keyCodec, valueCodec) }
+			return delegate
+		}
+
+		fun create(): DelegateSyncher {
+			return addInto(DelegateSyncher())
+		}
+
+		fun addInto(syncher: DelegateSyncher): DelegateSyncher {
+			constructors.forEach { it(syncher) }
+			return syncher
+		}
+	}
+
+	companion object {
+		const val END = 0
+		const val CLEAR = 1
+		const val ADD = 2
+		const val REMOVE = 3
+	}
+}
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/InputStreamUtils.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/InputStreamUtils.kt
@ -1,6 +1,7 @@
 package ru.dbotthepony.kommons.io

 import it.unimi.dsi.fastutil.bytes.ByteArrayList
+import ru.dbotthepony.kommons.math.Decimal
 import java.io.DataInput
 import java.io.EOFException
 import java.io.IOException
@ -210,3 +211,11 @@ fun InputStream.readUTF(): String {
 fun InputStream.readUUID(): UUID {
 	return UUID(readLong(), readLong())
 }
+
+fun InputStream.readDecimal(): Decimal {
+	val size = readVarInt()
+	require(size >= 0) { "Negative payload size: $size" }
+	val bytes = ByteArray(size)
+	read(bytes)
+	return Decimal.fromByteArray(bytes)
+}
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/MapChangeset.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/MapChangeset.kt
@ -1,23 +0,0 @@
-package ru.dbotthepony.kommons.io
-
-data class MapChangeset<out K, out V>(
-	val action: ChangesetAction,
-	val key: K?,
-	val value: V?
-) {
-	inline fun map(add: (K, V) -> Unit, remove: (K) -> Unit) {
-		when (action) {
-			ChangesetAction.ADD -> add.invoke(key!!, value!!)
-			ChangesetAction.REMOVE -> remove.invoke(key!!)
-			else -> {}
-		}
-	}
-
-	inline fun map(add: (K, V) -> Unit, remove: (K) -> Unit, clear: () -> Unit) {
-		when (action) {
-			ChangesetAction.CLEAR -> clear.invoke()
-			ChangesetAction.ADD -> add.invoke(key!!, value!!)
-			ChangesetAction.REMOVE -> remove.invoke(key!!)
-		}
-	}
-}
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/OutputStreamUtils.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/OutputStreamUtils.kt
@ -1,5 +1,6 @@
 package ru.dbotthepony.kommons.io

+import ru.dbotthepony.kommons.math.Decimal
 import ru.dbotthepony.kommons.util.IStruct2b
 import ru.dbotthepony.kommons.util.IStruct2d
 import ru.dbotthepony.kommons.util.IStruct2f
@ -250,3 +251,9 @@ fun OutputStream.writeStruct4b(value: IStruct4b) {
 	writeShort(value.component3().toInt() and 0xFF)
 	writeShort(value.component4().toInt() and 0xFF)
 }
+
+fun OutputStream.writeDecimal(value: Decimal) {
+	val bytes = value.toByteArray()
+	writeVarInt(bytes.size)
+	write(bytes)
+}
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/SetChangeset.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/SetChangeset.kt
@ -1,22 +0,0 @@
-package ru.dbotthepony.kommons.io
-
-data class SetChangeset<out V>(
-	val action: ChangesetAction,
-	val value: V?
-) {
-	inline fun map(add: (V) -> Unit, remove: (V) -> Unit) {
-		when (action) {
-			ChangesetAction.ADD -> add.invoke(value!!)
-			ChangesetAction.REMOVE -> remove.invoke(value!!)
-			else -> {}
-		}
-	}
-
-	inline fun map(add: (V) -> Unit, remove: (V) -> Unit, clear: () -> Unit) {
-		when (action) {
-			ChangesetAction.CLEAR -> clear.invoke()
-			ChangesetAction.ADD -> add.invoke(value!!)
-			ChangesetAction.REMOVE -> remove.invoke(value!!)
-		}
-	}
-}
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/StreamCodec.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/StreamCodec.kt
@ -7,22 +7,18 @@ import kotlin.reflect.KClass

 /**
 * Represents value which can be encoded onto or decoded from stream.
- *
- * Also provides [copy] and [compare] methods
 */
 interface StreamCodec<V> {
 	fun read(stream: DataInputStream): V
 	fun write(stream: DataOutputStream, value: V)

 	/**
-	 * defensive copy
+	 * Defensive copy
 	 */
 	fun copy(value: V): V

 	/**
-	 * Optional equality check override. Utilized to determine whenever e.g. network value is different from new value
-	 *
-	 * By default uses [Any.equals]
+	 * Optional custom equality check
 	 */
 	fun compare(a: V, b: V): Boolean {
 		return a == b
@ -170,6 +166,7 @@ val UUIDValueCodec = StreamCodec.Impl({ s -> UUID(s.readLong(), s.readLong()) },
 val VarIntValueCodec = StreamCodec.Impl(DataInputStream::readSignedVarInt, DataOutputStream::writeSignedVarInt)
 val VarLongValueCodec = StreamCodec.Impl(DataInputStream::readSignedVarLong, DataOutputStream::writeSignedVarLong)
 val BinaryStringCodec = StreamCodec.Impl(DataInputStream::readBinaryString, DataOutputStream::writeBinaryString)
+val DecimalValueCodec = StreamCodec.Impl(DataInputStream::readDecimal, DataOutputStream::writeDecimal)

 fun <E : Enum<E>> Class<E>.codec() = StreamCodec.Enum(this)
 fun <E : Enum<E>> KClass<E>.codec() = StreamCodec.Enum(this.java)
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/SynchedDelegates.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/SynchedDelegates.kt
@ -1,922 +0,0 @@
-@file:Suppress("DeprecatedCallableAddReplaceWith")
-
-package ru.dbotthepony.kommons.io
-
-import it.unimi.dsi.fastutil.io.FastByteArrayOutputStream
-import it.unimi.dsi.fastutil.objects.Reference2ObjectFunction
-import it.unimi.dsi.fastutil.objects.Reference2ObjectOpenHashMap
-import it.unimi.dsi.fastutil.objects.ReferenceArraySet
-import ru.dbotthepony.kommons.collect.ProxiedMap
-import ru.dbotthepony.kommons.collect.forValidRefs
-import ru.dbotthepony.kommons.util.Observer
-import ru.dbotthepony.kommons.util.ListenableDelegate
-import ru.dbotthepony.kommons.util.DelegateGetter
-import ru.dbotthepony.kommons.util.DelegateSetter
-import ru.dbotthepony.kommons.util.Listenable
-import java.io.DataInputStream
-import java.io.DataOutputStream
-import java.io.InputStream
-import java.lang.ref.WeakReference
-import java.util.*
-import java.util.function.Consumer
-import java.util.function.Supplier
-
-/**
- * Universal, one-to-many value synchronizer, allowing to synchronize values from server to client
- * anywhere, where input/output streams are supported
- */
-@Suppress("unused")
-class SynchedDelegates(private val callback: Runnable, private val alwaysCallCallback: Boolean) {
-	constructor() : this(Runnable {}, false)
-	constructor(callback: Runnable) : this(callback, false)
-
-	private var freeSlots = 0
-	// почему не удалять поля напрямую?
-	// чтоб не возникло проблем в состоянии гонки
-	// формируем пакет -> удаляем поле по обе стороны -> клиент принимает пакет -> клиент считывает неверные данные
-	// конечно, всё равно всё сломается если было удалено поле, которое находится в пакете
-	// но если поля нет в пакете, то всё окей
-	private val fields = ArrayList<AbstractValue?>(0)
-	private val observers = ArrayList<Observer>(0)
-	private val endpoints = ArrayList<WeakReference<Endpoint>>(1)
-	private var lastEndpointCleanup = System.nanoTime()
-	private var nextFieldID = 0
-	val hasObservers: Boolean get() = observers.isNotEmpty()
-	var isEmpty: Boolean = true
-		private set
-	val isNotEmpty: Boolean get() = !isEmpty
-	var isDirty: Boolean = false
-		private set(value) {
-			if (value != field) {
-				field = value
-
-				if (value && !alwaysCallCallback) {
-					callback.run()
-				}
-			}
-
-			if (alwaysCallCallback && value) {
-				callback.run()
-			}
-		}
-
-	private val boundEndpoints = Collections.synchronizedMap(WeakHashMap<Any, Endpoint>())
-
-	fun computeEndpointFor(obj: Any): Endpoint {
-		return boundEndpoints.computeIfAbsent(obj) { Endpoint() }
-	}
-
-	fun removeEndpointFor(obj: Any): Endpoint? {
-		return boundEndpoints.remove(obj)
-	}
-
-	fun endpointFor(obj: Any): Endpoint? {
-		return boundEndpoints[obj]
-	}
-
-	fun markClean() {
-		isDirty = false
-	}
-
-	private fun notifyEndpoints(dirtyField: AbstractValue) {
-		isDirty = true
-
-		forEachEndpoint {
-			it.addDirty(dirtyField)
-		}
-	}
-
-	private inline fun forEachEndpoint(execute: (Endpoint) -> Unit) {
-		synchronized(endpoints) {
-			endpoints.forValidRefs { execute.invoke(it) }
-		}
-	}
-
-	val defaultEndpoint = Endpoint()
-
-	inner class Endpoint {
-		init {
-			synchronized(endpoints) {
-				endpoints.add(WeakReference(this))
-
-				if (System.nanoTime() - lastEndpointCleanup >= 60) {
-					lastEndpointCleanup = System.nanoTime()
-
-					val iterator = endpoints.listIterator()
-
-					for (value in iterator) {
-						if (value.get() == null) {
-							iterator.remove()
-						}
-					}
-				}
-			}
-		}
-
-		private val dirty = ReferenceArraySet<AbstractValue>(4)
-
-		// use LinkedList because it is ensured memory is freed on LinkedList#clear
-		private val mapBacklogs = Reference2ObjectOpenHashMap<Map<*, *>, LinkedList<Pair<Any?, (DataOutputStream) -> Unit>>>()
-		private val setBacklogs = Reference2ObjectOpenHashMap<Set<*>, LinkedList<Pair<Any?, (DataOutputStream) -> Unit>>>()
-
-		var isDisabled: Boolean = false
-			private set
-
-		fun disable() {
-			if (isDisabled) return
-			isDisabled = true
-			mapBacklogs.clear()
-			dirty.clear()
-
-			synchronized(endpoints) {
-				val iterator = endpoints.listIterator()
-
-				for (value in iterator) {
-					if (value.get() === this || value.get() == null) {
-						iterator.remove()
-					}
-				}
-			}
-		}
-
-		init {
-			markDirty()
-		}
-
-		fun markDirty() {
-			if (isDisabled) return
-
-			for (field in fields) {
-				field?.markDirty(this)
-			}
-		}
-
-		internal fun addDirty(field: AbstractValue) {
-			if (isDisabled) return
-			dirty.add(field)
-		}
-
-		internal fun removeDirty(field: AbstractValue) {
-			dirty.remove(field)
-		}
-
-		internal fun <K, V> getMapBacklog(map: Map<K, V>): LinkedList<Pair<Any?, (DataOutputStream) -> Unit>> {
-			if (isDisabled) return LinkedList()
-
-			return mapBacklogs.computeIfAbsent(map, Reference2ObjectFunction {
-				LinkedList()
-			})
-		}
-
-		internal fun <K, V> removeMapBacklog(map: Map<K, V>) {
-			mapBacklogs.remove(map)
-		}
-
-		internal fun <V> getSetBacklog(set: Set<V>): LinkedList<Pair<Any?, (DataOutputStream) -> Unit>> {
-			if (isDisabled) return LinkedList()
-
-			return setBacklogs.computeIfAbsent(set, Reference2ObjectFunction {
-				LinkedList()
-			})
-		}
-
-		internal fun <V> removeSetBacklog(set: Set<V>) {
-			setBacklogs.remove(set)
-		}
-
-		fun collectData(): FastByteArrayOutputStream? {
-			if (isDisabled || dirty.isEmpty())
-				return null
-
-			val stream = FastByteArrayOutputStream()
-			val dataStream = DataOutputStream(stream)
-
-			for (field in dirty) {
-				stream.writeVarInt(field.id)
-				field.write(dataStream, this)
-			}
-
-			dirty.clear()
-			stream.write(0)
-
-			return stream
-		}
-	}
-
-	abstract inner class AbstractValue : Observer {
-		val id: Int
-
-		init {
-			if (freeSlots > 0) {
-				var found = -1
-
-				for (i in fields.indices) {
-					if (fields[i] == null) {
-						fields[i] = this
-						found = i + 1
-						freeSlots--
-						break
-					}
-				}
-
-				if (found == -1) {
-					throw RuntimeException("freeSlots = $freeSlots but no null entries in field list!")
-				} else {
-					id = found
-				}
-			} else {
-				fields.add(this)
-				id = fields.size
-				isEmpty = false
-			}
-		}
-
-		var isRemoved = false
-			private set
-
-		protected var isDirty = false
-		protected var isRemote = false
-
-		open fun remove() {
-			if (isRemoved)
-				return
-
-			isRemoved = true
-			freeSlots++
-			fields[id - 1] = null
-			observers.remove(this)
-			isEmpty = fields.all { it == null }
-
-			while (fields[fields.size - 1] == null) {
-				fields.removeAt(fields.size - 1)
-				freeSlots--
-			}
-
-			forEachEndpoint {
-				it.removeDirty(this)
-			}
-		}
-
-		open fun markDirty(endpoint: Endpoint) {
-			check(!isRemoved) { "Field was removed" }
-			endpoint.addDirty(this)
-		}
-
-		open fun markDirty() {
-			check(!isRemoved) { "Field was removed" }
-			notifyEndpoints(this)
-			isDirty = true
-		}
-
-		abstract fun write(stream: DataOutputStream, endpoint: Endpoint)
-		abstract fun read(stream: DataInputStream)
-	}
-
-	inner class RegularValue<T>(
-		value: T,
-		private val codec: StreamCodec<T>,
-		getter: DelegateGetter<T> = DelegateGetter.passthrough(),
-		setter: DelegateSetter<T> = DelegateSetter.passthrough()
-	) : AbstractValue(), ListenableDelegate<T> by ListenableDelegate.maskSmart(value, getter, setter) {
-		init {
-			addListener(Runnable {
-				if (!isDirty && !isRemote) {
-					notifyEndpoints(this)
-					isDirty = true
-				}
-			})
-		}
-
-		override fun observe(): Boolean {
-			return false
-		}
-
-		override fun write(stream: DataOutputStream, endpoint: Endpoint) {
-			codec.write(stream, get())
-			isDirty = false
-		}
-
-		override fun read(stream: DataInputStream) {
-			isRemote = true
-			accept(codec.read(stream))
-			isDirty = false
-		}
-	}
-
-	inner class ObservedValue<T>(
-		value: T,
-		private val codec: StreamCodec<T>,
-		getter: DelegateGetter<T> = DelegateGetter.passthrough(),
-		setter: DelegateSetter<T> = DelegateSetter.passthrough()
-	) : AbstractValue(), ListenableDelegate<T> by ListenableDelegate.maskSmart(value, getter, setter) {
-		private var observed = codec.copy(value)
-
-		init {
-			observers.add(this)
-
-			addListener(Runnable {
-				if (!isDirty && !isRemote) {
-					notifyEndpoints(this)
-					isDirty = true
-				}
-			})
-		}
-
-		override fun observe(): Boolean {
-			if (!isRemote) {
-				val get = get()
-
-				if (!codec.compare(get, observed)) {
-					observed = codec.copy(get)
-					isDirty = true
-				}
-			}
-
-			return isDirty
-		}
-
-		override fun write(stream: DataOutputStream, endpoint: Endpoint) {
-			codec.write(stream, get())
-			isDirty = false
-		}
-
-		override fun read(stream: DataInputStream) {
-			isRemote = true
-			accept(codec.read(stream))
-			isDirty = false
-		}
-	}
-
-	inner class ComputedValue<T>(getter: Supplier<T>, private val codec: StreamCodec<T>) : AbstractValue(), ListenableDelegate<T> {
-		private val shadow = ListenableDelegate.SmartShadow(getter, codec::compare, codec::copy)
-
-		override fun get(): T {
-			return shadow.get()
-		}
-
-		override fun accept(t: T) {
-			shadow.accept(t)
-		}
-
-		override fun addListener(listener: Consumer<T>): Listenable.L {
-			return shadow.addListener(listener)
-		}
-
-		override fun observe(): Boolean {
-			return shadow.observe()
-		}
-
-		init {
-			shadow.addListener(Runnable {
-				if (!isDirty && !isRemote) {
-					notifyEndpoints(this)
-					isDirty = true
-				}
-			})
-		}
-
-		override fun write(stream: DataOutputStream, endpoint: Endpoint) {
-			codec.write(stream, shadow.get())
-			isDirty = false
-		}
-
-		override fun read(stream: DataInputStream) {
-			isRemote = true
-			shadow.accept(codec.read(stream))
-			isDirty = false
-		}
-	}
-
-	@JvmName("vbyte") fun byte(value: Byte = 0, getter: DelegateGetter<Byte> = DelegateGetter.passthrough(), setter: DelegateSetter<Byte> = DelegateSetter.passthrough()): ListenableDelegate<Byte> = RegularValue(value, ByteValueCodec, getter, setter)
-	@JvmName("vshort") fun short(value: Short = 0, getter: DelegateGetter<Short> = DelegateGetter.passthrough(), setter: DelegateSetter<Short> = DelegateSetter.passthrough()): ListenableDelegate<Short> = RegularValue(value, ShortValueCodec, getter, setter)
-	@JvmName("vchar") fun char(value: Char = 0.toChar(), getter: DelegateGetter<Char> = DelegateGetter.passthrough(), setter: DelegateSetter<Char> = DelegateSetter.passthrough()): ListenableDelegate<Char> = RegularValue(value, CharValueCodec, getter, setter)
-	@JvmName("vint") fun int(value: Int = 0, getter: DelegateGetter<Int> = DelegateGetter.passthrough(), setter: DelegateSetter<Int> = DelegateSetter.passthrough()): ListenableDelegate<Int> = RegularValue(value, IntValueCodec, getter, setter)
-	@JvmName("vlong") fun long(value: Long = 0L, getter: DelegateGetter<Long> = DelegateGetter.passthrough(), setter: DelegateSetter<Long> = DelegateSetter.passthrough()): ListenableDelegate<Long> = RegularValue(value, LongValueCodec, getter, setter)
-	@JvmName("vfloat") fun float(value: Float = 0f, getter: DelegateGetter<Float> = DelegateGetter.passthrough(), setter: DelegateSetter<Float> = DelegateSetter.passthrough()): ListenableDelegate<Float> = RegularValue(value, FloatValueCodec, getter, setter)
-	@JvmName("vdouble") fun double(value: Double = 0.0, getter: DelegateGetter<Double> = DelegateGetter.passthrough(), setter: DelegateSetter<Double> = DelegateSetter.passthrough()): ListenableDelegate<Double> = RegularValue(value, DoubleValueCodec, getter, setter)
-	@JvmName("vboolean") fun boolean(value: Boolean = false, getter: DelegateGetter<Boolean> = DelegateGetter.passthrough(), setter: DelegateSetter<Boolean> = DelegateSetter.passthrough()): ListenableDelegate<Boolean> = RegularValue(value, BooleanValueCodec, getter, setter)
-
-	fun string(value: String, getter: DelegateGetter<String> = DelegateGetter.passthrough(), setter: DelegateSetter<String> = DelegateSetter.passthrough()): ListenableDelegate<String> = RegularValue(value, BinaryStringCodec, getter, setter)
-	fun uuid(value: UUID, getter: DelegateGetter<UUID> = DelegateGetter.passthrough(), setter: DelegateSetter<UUID> = DelegateSetter.passthrough()): ListenableDelegate<UUID> = RegularValue(value, UUIDValueCodec, getter, setter)
-
-	inner class Set<E>(
-		private val codec: StreamCodec<E>,
-		private val backingSet: MutableSet<E>,
-		private val callback: ((changes: Collection<SetChangeset<E>>) -> Unit)? = null,
-	) : AbstractValue() {
-		private fun pushBacklog(element: E, action: (DataOutputStream) -> Unit) {
-			check(!isRemote) { "Field marked as remote" }
-
-			val pair = element to action
-
-			forEachEndpoint {
-				val list = it.getSetBacklog(this)
-				val iterator = list.listIterator()
-
-				for (value in iterator) {
-					if (value.first == element) {
-						iterator.remove()
-					}
-				}
-
-				list.addLast(pair)
-			}
-		}
-
-		override fun observe(): Boolean {
-			return false
-		}
-
-		override fun remove() {
-			if (!isRemoved) {
-				forEachEndpoint { it.removeSetBacklog(this) }
-			}
-
-			super.remove()
-		}
-
-		override fun markDirty() {
-			check(!isRemoved) { "Field was removed" }
-
-			if (isRemote || endpoints.isEmpty())
-				return
-
-			isDirty = true
-
-			val endpoints = LinkedList<MutableList<Pair<Any?, (DataOutputStream) -> Unit>>>()
-
-			forEachEndpoint {
-				endpoints.add(it.getSetBacklog(this))
-				it.addDirty(this)
-			}
-
-			endpoints.forEach {
-				it.clear()
-				it.add(null to ClearBacklogEntry)
-			}
-
-			for (value in backingSet) {
-				val valueCopy = codec.copy(value)
-				val pair: Pair<Any?, (DataOutputStream) -> Unit> = valueCopy to { it.write(ChangesetAction.ADD.ordinal + 1); codec.write(it, valueCopy) }
-
-				endpoints.forEach {
-					it.add(pair)
-				}
-			}
-		}
-
-		override fun markDirty(endpoint: Endpoint) {
-			super.markDirty(endpoint)
-
-			endpoint.getSetBacklog(this).let {
-				it.clear()
-				it.add(null to ClearBacklogEntry)
-
-				for (value in backingSet) {
-					val valueCopy = codec.copy(value)
-					it.add(valueCopy to { it.write(ChangesetAction.ADD.ordinal + 1); codec.write(it, valueCopy) })
-				}
-			}
-		}
-
-		val value: MutableSet<E> = object : MutableSet<E> {
-			override fun add(element: E): Boolean {
-				if (backingSet.add(element)) {
-					if (!isRemote) {
-						markDirty()
-
-						val copy = codec.copy(element)
-
-						pushBacklog(element) {
-							it.write(ChangesetAction.ADD.ordinal + 1)
-							codec.write(it, copy)
-						}
-					}
-
-					return true
-				}
-
-				return false
-			}
-
-			override fun addAll(elements: Collection<E>): Boolean {
-				var any = false
-				elements.forEach { any = add(it) || any }
-				return any
-			}
-
-			override fun clear() {
-				if (backingSet.isNotEmpty()) {
-					backingSet.clear()
-
-					if (!isRemote) {
-						markDirty()
-
-						forEachEndpoint {
-							it.getSetBacklog(this@Set).let {
-								it.clear()
-								it.add(null to ClearBacklogEntry)
-							}
-						}
-					}
-				}
-			}
-
-			override fun iterator(): MutableIterator<E> {
-				return object : MutableIterator<E> {
-					private val parent = backingSet.iterator()
-					private var lastElement: Any? = Mark
-
-					override fun hasNext(): Boolean {
-						return parent.hasNext()
-					}
-
-					override fun next(): E {
-						return parent.next().also { lastElement = it }
-					}
-
-					override fun remove() {
-						parent.remove()
-						val lastElement = lastElement
-
-						if (lastElement !== Mark) {
-							this.lastElement = Mark
-
-							if (!isRemote) {
-								markDirty()
-
-								@Suppress("unchecked_cast")
-								pushBacklog(lastElement as E) {
-									it.write(ChangesetAction.REMOVE.ordinal + 1)
-									codec.write(it, lastElement as E)
-								}
-							}
-						}
-					}
-				}
-			}
-
-			override fun remove(element: E): Boolean {
-				if (backingSet.remove(element)) {
-					if (!isRemote) {
-						markDirty()
-
-						val copy = codec.copy(element)
-
-						pushBacklog(element) {
-							it.write(ChangesetAction.REMOVE.ordinal + 1)
-							codec.write(it, copy)
-						}
-					}
-
-					return true
-				}
-
-				return false
-			}
-
-			override fun removeAll(elements: Collection<E>): Boolean {
-				var any = false
-				elements.forEach { any = remove(it) || any }
-				return any
-			}
-
-			override fun retainAll(elements: Collection<E>): Boolean {
-				var any = false
-
-				val iterator = iterator()
-
-				for (value in iterator) {
-					if (value !in elements) {
-						any = true
-						iterator.remove()
-					}
-				}
-
-				return any
-			}
-
-			override val size: Int
-				get() = backingSet.size
-
-			override fun contains(element: E): Boolean {
-				return element in backingSet
-			}
-
-			override fun containsAll(elements: Collection<E>): Boolean {
-				return backingSet.containsAll(elements)
-			}
-
-			override fun isEmpty(): Boolean {
-				return backingSet.isEmpty()
-			}
-		}
-
-		override fun write(stream: DataOutputStream, endpoint: Endpoint) {
-			val list = endpoint.getSetBacklog(this)
-
-			for (value in list) {
-				value.second.invoke(stream)
-			}
-
-			stream.write(0)
-			list.clear()
-			isDirty = false
-		}
-
-		override fun read(stream: DataInputStream) {
-			if (!isRemote) {
-				isRemote = true
-				forEachEndpoint { it.removeSetBacklog(this) }
-			}
-
-			isDirty = false
-
-			var action = stream.read()
-			val changeset = LinkedList<SetChangeset<E>>()
-
-			while (action != 0) {
-				if ((action - 1) !in ChangesetActionList.indices) {
-					throw IllegalArgumentException("Unknown changeset action with index ${action - 1}")
-				}
-
-				when (ChangesetActionList[action - 1]) {
-					ChangesetAction.CLEAR -> {
-						changeset.add(SetChangeset(ChangesetAction.CLEAR, null))
-						backingSet.clear()
-					}
-
-					ChangesetAction.ADD -> {
-						val read = codec.read(stream)
-						changeset.add(SetChangeset(ChangesetAction.ADD, read))
-						backingSet.add(read)
-					}
-
-					ChangesetAction.REMOVE -> {
-						val read = codec.read(stream)
-						changeset.add(SetChangeset(ChangesetAction.REMOVE, read))
-						backingSet.remove(read)
-					}
-				}
-
-				action = stream.read()
-			}
-
-			callback?.invoke(changeset)
-		}
-	}
-
-	inner class Map<K, V>(
-		private val keyCodec: StreamCodec<K>,
-		private val valueCodec: StreamCodec<V>,
-		private val backingMap: MutableMap<K, V>,
-		private val callback: ((changes: Collection<MapChangeset<K, V>>) -> Unit)? = null,
-	) : AbstractValue() {
-		private var sentAllValues = false
-
-		private fun pushBacklog(key: Any?, value: (DataOutputStream) -> Unit) {
-			val pair = key to value
-
-			forEachEndpoint {
-				val list = it.getMapBacklog(this)
-				val iterator = list.listIterator()
-
-				for (e in iterator) {
-					if (e.first == key) {
-						iterator.remove()
-					}
-				}
-
-				list.addLast(pair)
-			}
-		}
-
-		override fun observe(): Boolean {
-			return false
-		}
-
-		override fun markDirty() {
-			check(!isRemoved) { "Field was removed" }
-
-			if (isRemote || endpoints.isEmpty())
-				return
-
-			isDirty = true
-			val backlogs = LinkedList<LinkedList<Pair<Any?, (DataOutputStream) -> Unit>>>()
-
-			forEachEndpoint {
-				it.addDirty(this)
-				val value = it.getMapBacklog(this)
-				backlogs.add(value)
-				value.clear()
-				value.add(null to ClearBacklogEntry)
-			}
-
-			for ((key, value) in backingMap) {
-				val valueCopy = valueCodec.copy(value)
-
-				val action = key to { it: DataOutputStream ->
-					it.write(ChangesetAction.ADD.ordinal + 1)
-					keyCodec.write(it, key)
-					valueCodec.write(it, valueCopy)
-				}
-
-				for (backlog in backlogs) {
-					backlog.add(action)
-				}
-			}
-		}
-
-		override fun markDirty(endpoint: Endpoint) {
-			check(!isRemoved) { "Field was removed" }
-
-			if (isRemote)
-				return
-
-			val backlog = endpoint.getMapBacklog(this)
-
-			backlog.clear()
-			backlog.add(null to ClearBacklogEntry)
-
-			for ((key, value) in backingMap) {
-				val valueCopy = valueCodec.copy(value)
-
-				backlog.add(key to {
-					it.write(ChangesetAction.ADD.ordinal + 1)
-					keyCodec.write(it, key)
-					valueCodec.write(it, valueCopy)
-				})
-			}
-		}
-
-		private fun lmarkDirty() {
-			if (!isDirty) {
-				notifyEndpoints(this@Map)
-				isDirty = true
-			}
-		}
-
-		val value: MutableMap<K, V> = object : ProxiedMap<K, V>(backingMap) {
-			override fun onClear() {
-				if (isRemote || endpoints.isEmpty())
-					return
-
-				forEachEndpoint { endpoint ->
-					endpoint.getMapBacklog(this@Map).let {
-						it.clear()
-						it.add(null to ClearBacklogEntry)
-					}
-				}
-
-				lmarkDirty()
-				this@SynchedDelegates.isDirty = true
-			}
-
-			override fun onValueAdded(key: K, value: V) {
-				if (isRemote || endpoints.isEmpty())
-					return
-
-				val keyCopy = keyCodec.copy(key)
-				val valueCopy = valueCodec.copy(value)
-
-				pushBacklog(key) {
-					it.write(ChangesetAction.ADD.ordinal + 1)
-					keyCodec.write(it, keyCopy)
-					valueCodec.write(it, valueCopy)
-				}
-
-				lmarkDirty()
-			}
-
-			override fun onValueRemoved(key: K, value: V) {
-				if (isRemote || endpoints.isEmpty())
-					return
-
-				val keyCopy = keyCodec.copy(key)
-
-				pushBacklog(key) {
-					it.write(ChangesetAction.REMOVE.ordinal + 1)
-					keyCodec.write(it, keyCopy)
-				}
-
-				lmarkDirty()
-			}
-		}
-
-		override fun write(stream: DataOutputStream, endpoint: Endpoint) {
-			sentAllValues = false
-			isDirty = false
-
-			val iterator = endpoint.getMapBacklog(this).listIterator()
-
-			for (entry in iterator) {
-				entry.second.invoke(stream)
-				iterator.remove()
-			}
-
-			stream.write(0)
-		}
-
-		override fun read(stream: DataInputStream) {
-			if (!isRemote) {
-				isRemote = true
-				forEachEndpoint { it.removeMapBacklog(this) }
-			}
-
-			isDirty = false
-
-			val changeset = LinkedList<MapChangeset<K, V>>()
-			var readAction = stream.read() - 1
-
-			while (readAction != -1) {
-				if (readAction >= ChangesetActionList.size) {
-					throw IndexOutOfBoundsException("Unknown map action with ID $readAction")
-				}
-
-				when (ChangesetActionList[readAction]) {
-					ChangesetAction.CLEAR -> {
-						backingMap.clear()
-						changeset.add(ClearMapChangeset)
-					}
-
-					ChangesetAction.ADD -> {
-						val key = keyCodec.read(stream)
-						val value = valueCodec.read(stream)
-						backingMap[key] = value
-						changeset.add(MapChangeset(ChangesetAction.ADD, key, value))
-					}
-
-					ChangesetAction.REMOVE -> {
-						val key = keyCodec.read(stream)
-						backingMap.remove(key)
-						changeset.add(MapChangeset(ChangesetAction.REMOVE, key, null))
-					}
-				}
-
-				readAction = stream.read() - 1
-			}
-
-			if (changeset.size != 0) {
-				callback?.invoke(changeset)
-			}
-		}
-	}
-
-	/**
-	 * marks all fields dirty, invalidates mappings for each endpoint
-	 */
-	fun invalidate() {
-		for (field in fields) {
-			field?.markDirty()
-		}
-	}
-
-	/**
-	 * Observe changes of all fields with backing computation lambda
-	 */
-	fun observe(): Boolean {
-		var changes = false
-
-		if (observers.isNotEmpty()) {
-			for (field in observers) {
-				changes = field.observe() || changes
-			}
-		}
-
-		return changes
-	}
-
-	/**
-	 * [defaultEndpoint]#collectNetworkPayload
-	 */
-	fun collectData(): FastByteArrayOutputStream? {
-		check(!defaultEndpoint.isDisabled) { "Default endpoint is not used" }
-		observe()
-		val values = defaultEndpoint.collectData()
-		markClean()
-		return values
-	}
-
-	fun read(stream: InputStream): Int {
-		var fieldId = stream.readVarInt()
-		var i = 0
-		val dataStream = DataInputStream(stream)
-
-		while (fieldId != 0) {
-			val field = fields.getOrNull(fieldId - 1) ?: throw IllegalArgumentException("Unknown field ID ${fieldId - 1}")
-			field.read(dataStream)
-			fieldId = stream.readVarInt()
-			i++
-		}
-
-		return i
-	}
-
-	private object Mark
-
-	companion object {
-		private val ClearBacklogEntry = { stream: DataOutputStream -> stream.write(ChangesetAction.CLEAR.ordinal + 1) }
-		private val ChangesetActionList = ChangesetAction.values()
-		private val ClearMapChangeset = MapChangeset(ChangesetAction.CLEAR, null, null)
-	}
-}
--- a/src/main/kotlin/ru/dbotthepony/kommons/util/Delegate.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/util/Delegate.kt
@ -4,7 +4,9 @@ package ru.dbotthepony.kommons.util

 import java.util.function.Consumer
 import java.util.function.Supplier
+import kotlin.reflect.KMutableProperty0
 import kotlin.reflect.KProperty
+import kotlin.reflect.KProperty0

 /**
 * [Supplier] and [Consumer] combined in single interface
@ -48,7 +50,11 @@ interface Delegate<V> : Supplier<V>, Consumer<V> {
 		}
 	}

-	class Of<V>(getter: Supplier<V>, setter: Consumer<V>) : Delegate<V>, Supplier<V> by getter, Consumer<V> by setter
+	class Of<V>(getter: Supplier<V>, setter: Consumer<V>) : Delegate<V>, Supplier<V> by getter, Consumer<V> by setter {
+		constructor(prop: KMutableProperty0<V>) : this(prop::get, prop::set)
+		@Deprecated("Warning: Using read-only property as delegate")
+		constructor(prop: KProperty0<V>) : this(prop::get, Consumer { })
+	}
 }

 operator fun <V> Supplier<V>.getValue(ref: Any?, property: KProperty<*>): V {
--- a/src/main/kotlin/ru/dbotthepony/kommons/util/Listenable.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/util/Listenable.kt
@ -25,22 +25,21 @@ interface Listenable<V> {
 	 */
 	class Impl<V> : Listenable<V>, Consumer<V> {
 		private inner class L(val callback: Consumer<V>) : Listenable.L {
-			private var isRemoved = false
-
 			init {
 				subscribers.add(this)
 			}

 			override fun remove() {
-				if (!isRemoved) {
-					isRemoved = true
-					subscribers.remove(this)
-				}
+				subscribers.remove(this)
 			}
 		}

 		private val subscribers = CopyOnWriteArrayList<L>()

+		fun clear() {
+			subscribers.clear()
+		}
+
 		override fun addListener(listener: Consumer<V>): Listenable.L {
 			return L(listener)
 		}
@ -68,6 +67,10 @@ interface Listenable<V> {

 		private val subscribers = CopyOnWriteArrayList<L>()

+		fun clear() {
+			subscribers.clear()
+		}
+
 		override fun addListener(listener: Runnable): Listenable.L {
 			return L(listener)
 		}
--- a/src/main/kotlin/ru/dbotthepony/kommons/util/ListenableDelegate.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/util/ListenableDelegate.kt
@ -4,6 +4,7 @@ import java.util.concurrent.locks.ReentrantLock
 import java.util.function.Consumer
 import java.util.function.Supplier
 import kotlin.concurrent.withLock
+import kotlin.reflect.KProperty0

 interface ListenableDelegate<V> : Delegate<V>, Listenable<V> {
 	class UnboundBox<V> : ListenableDelegate<V> {
@ -20,6 +21,10 @@ interface ListenableDelegate<V> : Delegate<V>, Listenable<V> {
 			return get as V
 		}

+		fun clearListeners() {
+			listeners.clear()
+		}
+
 		override fun accept(t: V) {
 			value = t
 		}
@ -34,6 +39,10 @@ interface ListenableDelegate<V> : Delegate<V>, Listenable<V> {
 			return listeners.addListener(listener)
 		}

+		fun clearListeners() {
+			listeners.clear()
+		}
+
 		override fun get(): V {
 			return value
 		}
@ -49,6 +58,10 @@ interface ListenableDelegate<V> : Delegate<V>, Listenable<V> {
 	class SmartBox<V>(value: V, private val getter: DelegateGetter<V>, private val setter: DelegateSetter<V>) : ListenableDelegate<V> {
 		private val value = Box(value)

+		fun clearListeners() {
+			value.clearListeners()
+		}
+
 		override fun addListener(listener: Consumer<V>): Listenable.L {
 			return value.addListener(listener)
 		}
@ -94,6 +107,10 @@ interface ListenableDelegate<V> : Delegate<V>, Listenable<V> {
 			return listeners.addListener(listener)
 		}

+		fun clearListeners() {
+			listeners.clear()
+		}
+
 		override fun observe(): Boolean {
 			if (shadow !== Companion)
 				return false
@ -142,6 +159,8 @@ interface ListenableDelegate<V> : Delegate<V>, Listenable<V> {
 	}

 	class Shadow<V>(parent: Supplier<V>) : AbstractShadow<V>(parent) {
+		constructor(parent: KProperty0<V>) : this(parent::get)
+
 		override fun compare(a: V, b: V): Boolean {
 			return a == b
 		}
@ -151,7 +170,9 @@ interface ListenableDelegate<V> : Delegate<V>, Listenable<V> {
 		}
 	}

-	class SmartShadow<V>(parent: Supplier<V>, private val comparator: (V, V) -> Boolean, private val copy: (V) -> V) : AbstractShadow<V>(parent) {
+	class CustomShadow<V>(parent: Supplier<V>, private val comparator: (V, V) -> Boolean, private val copy: (V) -> V) : AbstractShadow<V>(parent) {
+		constructor(parent: KProperty0<V>, comparator: (V, V) -> Boolean, copy: (V) -> V) : this(parent::get, comparator, copy)
+
 		override fun compare(a: V, b: V): Boolean {
 			return comparator(a, b)
 		}