From 7011ab8ace89f6ab0f79c65468c1910248a53192 Mon Sep 17 00:00:00 2001
From: DBotThePony <dbotthepony@yandex.ru>
Date: Sun, 18 Feb 2024 21:19:59 +0700
Subject: [PATCH] Get rid of "intermediate" btreedb class

---
 gradle.properties                             |  2 +-
 .../ru/dbotthepony/kommons/io/BTreeDB.kt      | 31 -------------------
 .../ru/dbotthepony/kommons/io/BTreeDB6.kt     | 18 ++++++-----
 3 files changed, 11 insertions(+), 40 deletions(-)
 delete mode 100644 src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB.kt

diff --git a/gradle.properties b/gradle.properties
index 1e62ca3..e3ef8c9 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -4,7 +4,7 @@ kotlin.code.style=official
 specifyKotlinAsDependency=false
 
 projectGroup=ru.dbotthepony.kommons
-projectVersion=2.5.0
+projectVersion=2.6.0
 
 guavaDepVersion=33.0.0
 gsonDepVersion=2.8.9
diff --git a/src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB.kt b/src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB.kt
deleted file mode 100644
index d3cf82d..0000000
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB.kt
+++ /dev/null
@@ -1,31 +0,0 @@
-package ru.dbotthepony.kommons.io
-
-import ru.dbotthepony.kommons.util.KOptional
-import java.io.Closeable
-import java.io.File
-
-/**
- * For actual implementation, see [BTreeDB6].
- */
-abstract class BTreeDB<K, V> : Closeable {
-	abstract val file: File
-	abstract val blockSize: Int
-
-	abstract operator fun contains(key: K): Boolean
-
-	/**
-	 * Reads data at specified [key]
-	 */
-	abstract fun read(key: K): KOptional<V>
-	abstract fun findAllKeys(): List<K>
-
-	abstract fun write(key: K, value: V)
-}
-
-abstract class ByteDataBTreeDB<K> : BTreeDB<K, ByteArray>() {
-	abstract fun write(key: K, value: ByteArray, offset: Int, length: Int)
-
-	final override fun write(key: K, value: ByteArray) {
-		return write(key, value, 0, value.size)
-	}
-}
diff --git a/src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB6.kt b/src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB6.kt
index c01edc0..c4a06f5 100644
--- a/src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB6.kt
+++ b/src/main/kotlin/ru/dbotthepony/kommons/io/BTreeDB6.kt
@@ -8,6 +8,7 @@ import it.unimi.dsi.fastutil.objects.ObjectArrayList
 import it.unimi.dsi.fastutil.objects.ObjectOpenHashSet
 import ru.dbotthepony.kommons.util.CarriedExecutor
 import ru.dbotthepony.kommons.util.KOptional
+import java.io.Closeable
 import java.io.DataInputStream
 import java.io.DataOutputStream
 import java.io.File
@@ -73,9 +74,10 @@ private fun readHeader(reader: RandomAccessFile, required: Char) {
 // TODO: Defragmenting
 // TODO: Add keys to DATA blocks, so entire tree can be reconstructed from scratch in event of both trees become unreadable
 // TODO: Changeset counter (to determine write-in-progress blocks/trees, to ignore them when reconstructing tree)
-// TODO: Tree rotations (rebalancing)
+// TODO: Tree rotations (rebalancing), tree height tracking, weighted subtree splitting
 // TODO: Removal of keys
-class BTreeDB6 private constructor(override val file: File, private var reader: RandomAccessFile, private val sync: Boolean) : ByteDataBTreeDB<ByteKey>() {
+// TODO: Faster free bitmap scan
+class BTreeDB6 private constructor(val file: File, private var reader: RandomAccessFile, private val sync: Boolean) : Closeable {
 	constructor(file: File, sync: Boolean = true) : this(file, RandomAccessFile(file, "rw"), sync)
 
 	init {
@@ -97,8 +99,8 @@ class BTreeDB6 private constructor(override val file: File, private var reader:
 		reader.close()
 	}
 
-	override val blockSize = reader.readInt()
-	private val effectiveBlockSize = blockSize - 9
+	val blockSize = reader.readInt()
+	val effectiveBlockSize = blockSize - 9
 
 	init {
 		require(blockSize >= 64) { "Degenerate block size: $blockSize" }
@@ -235,11 +237,11 @@ class BTreeDB6 private constructor(override val file: File, private var reader:
 		}
 	}
 
-	override fun contains(key: ByteKey): Boolean {
+	operator fun contains(key: ByteKey): Boolean {
 		return searchForBlock(key) != null
 	}
 
-	override fun read(key: ByteKey): KOptional<ByteArray> {
+	fun read(key: ByteKey): KOptional<ByteArray> {
 		val data = searchForBlock(key)
 
 		if (data != null) {
@@ -274,7 +276,7 @@ class BTreeDB6 private constructor(override val file: File, private var reader:
 		}
 	}
 
-	override fun findAllKeys(): List<ByteKey> {
+	fun findAllKeys(): List<ByteKey> {
 		if (rootBlockIndex == INVALID_BLOCK_INDEX) {
 			return emptyList()
 		}
@@ -284,7 +286,7 @@ class BTreeDB6 private constructor(override val file: File, private var reader:
 		return result
 	}
 
-	override fun write(key: ByteKey, value: ByteArray, offset: Int, length: Int) {
+	fun write(key: ByteKey, value: ByteArray, offset: Int, length: Int) {
 		if (rootBlockIndex == INVALID_BLOCK_INDEX) {
 			// create LEAF node for root
 			val block = allocBlock(BlockType.LEAF)