Add FileManager, File cleanup, Logger

src/main/kotlin/nl/astraeus/persistence/Datastore.kt

@@ -5,7 +5,6 @@ import java.io.ObjectInputStream
 import java.io.ObjectOutputStream
 import java.io.Serializable
 import java.text.DecimalFormat
-import java.util.*
 import java.util.concurrent.ConcurrentHashMap
 import kotlin.reflect.KClass
 
@@ -35,10 +34,6 @@ class Datastore(
   private val indexes: MutableMap<Class<*>, MutableMap<String, PersistableIndex>> = ConcurrentHashMap()
 
   init {
-    if (!directory.exists()) {
-      directory.mkdirs()
-    }
-
     for (index in indexes) {
       this.indexes.getOrPut(index.cls) {
         ConcurrentHashMap()
@@ -48,49 +43,43 @@ class Datastore(
     loadTransactions()
   }
 
-  private fun loadTransactions() {
-    synchronized(this) {
-      val snapshots: Array<File>? = directory.listFiles { _, name -> name.startsWith("transaction-") && name.endsWith(".snp") }
-      val files: Array<File>? = directory.listFiles { _, name -> name.startsWith("transaction-") && name.endsWith(".trn") }
+  override fun toString(): String {
+    return "Datastore(directory=${fileManager.directory}, classes=${data.keys.size}, indexes=${indexes.keys.size})"
+  }
 
-      var lastSnapshot: Long? = null
-      var lastSnapshotFile: File? = null
-
-      snapshots?.let {
-        it.forEach {
-          val trnx = getTrnx(it)
-          if (lastSnapshot == null || trnx > (lastSnapshot ?: 0L)) {
-            lastSnapshot = trnx
-            lastSnapshotFile = it
-          }
-        }
+  // print status, show number of entries for each class and index
+  fun printStatus() {
+    println(this)
+    for ((cls, typeData) in data) {
+      println("  ${cls.simpleName}: ${typeData.data.size}")
+      for ((name, index) in indexes.getOrDefault(cls, mutableMapOf())) {
+        println("    $name: ${index.index.size}")
       }
+    }
+  }
 
-      val lastSnapshotFile2 = fileManager.findLastSnapshot()
+  private fun loadTransactions() {
+    val start = System.nanoTime()
+
+    synchronized(this) {
+      val (lastSnapshot, lastSnapshotFile) = fileManager.findLastSnapshot()
 
       if (lastSnapshotFile != null) {
-        ObjectInputStream(lastSnapshotFile?.inputStream()).use { ois ->
+        ObjectInputStream(lastSnapshotFile.inputStream()).use { ois ->
           readSnapshot(ois)
         }
       }
 
-      val trns = fileManager.findTransactionsAfter(lastSnapshot ?: 0L)
+      val transactions = fileManager.findTransactionsAfter(lastSnapshot ?: 0L)
 
-      files?.also { snaphotFiles ->
-        Arrays.sort(snaphotFiles) { o1, o2 -> if (getTrnx(o1) > getTrnx(o2)) 1 else -1}
-
-        snaphotFiles.forEach { file ->
-          if (getTrnx(file) > (lastSnapshot ?: 0L)) {
-            ObjectInputStream(file.inputStream()).use { ois ->
-              val transactionNumber = ois.readLong()
-              nextTransactionNumber = transactionNumber + 1
-              val actions = ois.readObject() as MutableList<Action>
-              execute(actions)
-            }
-          }
+      transactions?.forEach { file ->
+        ObjectInputStream(file.inputStream()).use { ois ->
+          readTransaction(ois)
         }
       }
     }
+
+    Logger.debug("Loaded transactions in ${(System.nanoTime() - start) / 1_000_000}ms")
   }
 
   private fun getTrnx(file: File): Long {
@@ -112,6 +101,7 @@ class Datastore(
             typeData.data[action.obj.id] = action.obj
 
             for (index in indexes[action.obj::class.java]?.values ?: listOf()) {
+              index.remove(action.obj.id)
               index.add(action.obj as Persistable)
             }
           }
@@ -120,7 +110,7 @@ class Datastore(
             typeData.data.remove(action.obj.id)
 
             for (index in indexes[action.obj::class.java]?.values ?: listOf()) {
-              index.remove(action.obj)
+              index.remove(action.obj.id)
             }
           }
         }
@@ -161,17 +151,29 @@ class Datastore(
   fun storeActions(actions: MutableList<Action>) {
     if (actions.isNotEmpty()) {
       synchronized(this) {
-        val number = transactionFormatter.format(nextTransactionNumber)
-        val file = File(directory, "transaction-$number.trn")
-        ObjectOutputStream(file.outputStream()).use { oos ->
-          oos.writeLong(nextTransactionNumber++)
-          oos.writeObject(actions)
-        }
+        writeTransaction(actions)
       }
     }
   }
 
+  private fun readTransaction(ois: ObjectInputStream) {
+    val transactionNumber = ois.readLong()
+    nextTransactionNumber = transactionNumber + 1
+    val actions = ois.readObject() as MutableList<Action>
+    execute(actions)
+  }
+
+  private fun writeTransaction(actions: MutableList<Action>) {
+    val number = transactionFormatter.format(nextTransactionNumber)
+    val file = File(directory, "transaction-$number.trn")
+    ObjectOutputStream(file.outputStream()).use { oos ->
+      oos.writeLong(nextTransactionNumber++)
+      oos.writeObject(actions)
+    }
+  }
+
   fun snapshot() {
+    val start = System.nanoTime()
     synchronized(this) {
       val number = transactionFormatter.format(nextTransactionNumber)
       val file = File(directory, "transaction-$number.snp")
@@ -189,6 +191,7 @@ class Datastore(
         }
       }
     }
+    Logger.debug("Snapshot in ${(System.nanoTime() - start) / 1_000_000}ms")
   }
 
   private fun readSnapshot(ois: ObjectInputStream) {
@@ -226,4 +229,8 @@ class Datastore(
     }
   }
 
+  fun removeOldFiles() {
+    fileManager.removeOldFiles()
+  }
+
 }